NETWORK-ASSIGNED RESOURCES TO MINIMIZE TRANSMISSION COLLISIONS IN VEHICLE-TO-VEHICLE COMMUNICATIONS

Abstract

The devices, systems, and methods discussed herein involve a base station (e.g., gNB) that employs a broadcast technology such as the Multimedia Broadcast Multicast Service (MBMS) to relay hidden-node information to the neighboring user equipment (UE) devices. In some examples, a base station receives a report based on data acquired by at least one non-communication sensor of a first UE device. Based on the report, the base station assigns communication resources to a second UE device and a third UE device. The base station transmits one or more messages that collectively identify assignment of the first communication resources and the second communication resources.

Description

FIELD

This invention generally relates to wireless communications and more particularly to transmission collision avoidance in vehicle-to-vehicle communications.

BACKGROUND

Data transmission collisions create problems in networks in which multiple devices are attempting to transmit data. Thus, avoiding data transmission collisions is advantageous.

SUMMARY

The devices, systems, and methods discussed herein involve a base station (e.g., gNB) that employs a broadcast technology such as the Multimedia Broadcast Multicast Service (MBMS) to relay hidden-node information to the neighboring user equipment (UE) devices. In some examples, a base station receives a report based on data acquired by at least one non-communication sensor of a first UE device. Based on the report, the base station assigns communication resources to a second UE device and a third UE device. The base station transmits one or more messages that collectively identify assignment of the first communication resources and the second communication resources.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a block diagram of an example of a hidden-node scenario.

FIG. 1B is a block diagram of an example of a system in which a first user equipment (UE) device determines a likelihood that two other UE devices may be hidden nodes to each other and transmits a message to one of the other UE devices, which results in a reduction in interference between the two other UE devices.

FIG. 10 is a block diagram of an example of a system in which a first base station receives at least one report based on data acquired by at least one non-communication sensor. Based on the at least one report, the base station transmits a message to a UE device that results in the UE device refraining from using communication resources that will interfere with transmissions by other UE devices.

FIG. 1D is a block diagram of an example of a system in which a base station receives a report based on data acquired by at least one non-communication sensor and assigns communication resources to UE devices based on the report.

FIG. 2A is a block diagram of an example of the base stations shown in FIGS. 1C and 1D.

FIG. 2B is a block diagram of an example of the user equipment devices shown in FIGS. 1A-1D.

FIG. 3 is a flowchart of an example of a method in which a first base station receives a first report based on data acquired by at least one non-communication sensor of a first UE device. Based on the first report, the base station assigns communication resources to a second UE device and a third UE device and transmits the assignments to the second and third UE devices.

DETAILED DESCRIPTION

The examples discussed below are generally directed to vehicle-to-everything (V2X) communication, which is the passing of information from a vehicle to any entity that may affect the vehicle or that the vehicle may affect. For example, V2X is a vehicular communication system that incorporates other, more specific types of communication, including vehicle-to-vehicle (V2V), V2I (vehicle-to-infrastructure), V2N (vehicle-to-network), V2P (vehicle-to-pedestrian), V2D (vehicle-to-device), and V2G (vehicle-to-grid). There are two types of V2X communication technology depending on the underlying technology being used: V2X based on Institute of Electrical and Electronics Engineers 802.11, and cellular-based V2X (C-V2X). Some examples of V2X protocols include Long-Term Evolution (LTE) (Rel-14) V2X Mode 3 and Mode 4 and 5G New Radio (NR) V2X Mode 1 and Mode 2.

In some of the examples described herein, the wireless communication devices are user equipment devices (UEs) or vehicle user equipment devices (VUEs) that exchange data (e.g., in the Extended Sensor use case), which is gathered through local sensors, or live video data among vehicles, Road Side Units (RSUs), devices of pedestrians, and V2X application servers. As will be discussed more fully below, in some cases, vehicles equipped with an Advanced Driver Assistance System (ADAS) use sensors such as cameras, radar, and/or lidar to sense the neighboring environment and other vehicles.

However, with multiple vehicles transmitting signals within the same general area, data transmission collisions may occur, which wastes system resources when signals must be resent. Moreover, delayed or failed signal transmissions may also cause safety issues for the vehicles and pedestrians in the area. Thus, it may be advantageous to implement inter-UE coordination (IUC) messaging to enhance Mode 2 resource allocation performance, which reduces the likelihood of data transmission collisions since the UEs can be allocated communication resources that are less likely to interfere with each other.

When considering data transmission collisions, there are two main scenarios. In the first scenario, the collision between two data transmissions has already occurred, and the receiving UEs have detected the collision. The second scenario is when there is a potential for two data transmissions to collide, but the actual data transmissions have not yet occurred. The second scenario happens when two transmitting UEs are unaware of each other and both happen to reserve the same transmission resources for their respective future data transmissions. The first and the second scenarios are referred to as “post-collision” and “potential-collision,” respectively.

In NR V2X, the transmitting UEs are not allowed to reserve their initial transmissions and are half-duplex constrained, meaning they cannot simultaneously transmit and receive signals. As a consequence, in the “post-collision” scenario, two transmitting UEs could accidentally select the same resource or time-slot for their transmissions, causing a data collision. Similarly, a transmitting UE and a receiving UE, which are paired to each other, could accidentally select the same resource or time-slot for their transmissions, which results in an unsuccessful data reception.

To solve this problem, NR V2X feedback (e.g., a 1-bit Physical Sidelink Feedback Channel (PSFCH)) is proposed as an IUC-based solution. In the first case, the intended receiving UEs transmit the 1-bit PSFCH to their respective transmitting UEs, informing them to perform a resource reselection before the next (re-)transmission. In the second case, a third UE (1) detects the half-duplex situation when the transmit-receive paired UEs overlap each other's transmissions, and (2) transmits the PSFCH to one of the UEs of the transmit-receive paired UEs, informing the UE to perform resource reselection.

The “potential-collision” is a much more challenging scenario. In order to avoid potential-collisions, the transmit UEs must be able to predict them before the data transmissions occur. The main cause for the potential-collisions is when two transmitting UEs are in a hidden-node situation. A typical hidden-node situation occurs when there is a blockage such that the two transmitting UEs' transmissions are unable to reach each other but still cause interference to each other's respective receiving UEs.

An example of a hidden-node situation can be seen in FIG. 1A in which various UEs are moving on roadway 101. More specifically, FIG. 1A shows that transmissions from UE 2, 104, and UE 3, 106, are unable to reach each other due to object 110 (e.g., a building). However, transmissions from UE2, 104, can cause interference with UE 4, 108, which is a receiving UE for UE 3, 106. Similarly, transmissions from UE3, 106, can cause interference with UE 1, 102, which is a receiving UE for UE 2, 104. The transmissions to intended recipients are shown as solid arrows in FIG. 1A, and the transmissions that cause unintended interference are shown as dashed arrows in FIG. 1A. The hidden-node situation is preventable if the respective hidden-node transmitting UEs (e.g., UE 2, 104, and UE 3, 106 in FIG. 1A) avoid using the same transmission resource.

One solution to the hidden-node situation is to support IUC messaging from the receiving UE to inform the transmitting UE of a list of (not-)preferred resources for transmission. However, transmission of the list itself could cause interference. Moreover, this type of coordination only works after the transmission collision between the hidden-nodes has already occurred and been detected.

Another solution is to assign orthogonal resources to prevent hidden-node occurrences. For example, different resource pools could be assigned based on the UE's heading direction. Thus, a transmitting UE heading in the north-south direction is assigned resource pool A, and another transmitting UE heading in the east-west direction is assigned resource pool B for their respective transmissions. The resource pool assignment is done via the network configuration procedure.

Although the resource pool assignment mitigates the hidden-node problem, the resource pool assignment scheme requires a pre-allocation of resources for each direction. This pre-allocation of resources may cause an inefficiency in resource utilization, especially during low-traffic time periods. To mitigate the resource underutilization, the resource pool assignment scheme may be disabled during low-traffic time-periods, which requires constant traffic-monitoring and the control signaling overhead to disable/enable the scheme.

As an improvement to the orthogonal resource allocation method, a local gNB/RSU (e.g., base station (gNodeB)/Roadside Unit) could dynamically assign resource pools to different groups of UEs approaching the intersection and/or a region. For example, consider a scenario in which a gNB/RSU is located on top of the object 110 (e.g., building) in FIG. 1A, the gNB/RSU first senses the UEs approaching the intersection. This could be done either by detecting the UE's uplink/sidelink transmissions or using visual-camera and lidar/radar-detection sensing technologies.

After the hidden-nodes (e.g., UE 2, 104 and UE 3, 106) are identified, the gNB/RSU broadcasts orthogonal resource assignment messages on the cellular band or the V2X band (e.g., sidelink transmission) to the respective groups of UEs. However, the resource assignment broadcasting in the V2X band may crowd out other V2V transmissions in the precious V2X resources. This overhead is partially reduced if the gNB/RSU unicasts or groupcasts messages to the targeted UE or group of selected UEs approaching the intersection, respectively.

For the resource assignment broadcasts, sidelink (SL) transmissions are preferred due to the lower signaling overhead and less latency. By comparison, for cellular band transmissions, the gNB/RSU must either broadcast a periodic System Information Block (SIB) message or transmit dedicated transmissions, causing large latency or paging signaling overhead, respectively. Furthermore, there is a deployment cost of installing a gNB/RSU at every location where a hidden-node problem could occur.

The devices, systems, and methods discussed herein involve a base station (e.g., gNB) that employs a broadcast technology such as the Multimedia Broadcast Multicast Service (MBMS) to relay hidden-node information to the neighboring user equipment (UE) devices. In some examples, a base station receives a report based on data acquired by at least one non-communication sensor of a first UE device. Based on the report, the base station assigns communication resources to a second UE device and a third UE device. The base station transmits one or more messages that collectively identify assignment of the first communication resources and the second communication resources.

As used herein, the terms “hidden-node,” “hidden-node vehicle,” and “hidden-node UE” may all be used interchangeably to refer to a vehicle in which a UE is temporarily or permanently located and that is determined to at least potentially be a hidden-node relative to at least one other UE.

Although the different examples described herein may be discussed separately, any of the features of any of the examples may be added to, omitted from, or combined with any other example. Similarly, any of the features of any of the examples may be performed in parallel or performed in a different manner/order than that described or shown herein.

FIG. 1B is a block diagram of an example of a system 100 in which a first user equipment (UE) device determines a likelihood that two other UE devices may be hidden nodes to each other and transmits a message to one of the other UE devices, which results in a reduction in interference between the two other UE devices. FIG. 1B shows various UE devices operating on roadway 101. The UE devices operate in accordance with at least one revision of the 3rd Generation Partnership Project 5G New Radio (3GPP 5G NR) communication specification. In other examples, the UE devices may operate in accordance with other communication specifications.

In the interest of brevity, FIG. 1B only depicts four UE devices. However, any number of UE devices may be utilized. As shown in FIG. 2, user equipment device (UE) 102 comprises controller 216, transmitter 218, receiver 214, and sensor 220, as well as other electronics, hardware, and software code. UE 102 may also be referred to herein as a VUE or simply as a wireless communication device (WCD). UE 102 is wirelessly connected to a radio access network (not shown) via one or more base stations (not shown), which provide various wireless services to UE 102. For the example shown in FIG. 1B, UE 102 operates in accordance with at least one revision of the 3rd Generation Partnership Project 5G New Radio (3GPP 5G NR) communication specification. In other examples, UE 102 may operate in accordance with other communication specifications. For the example shown in FIG. 1B, all of the UEs have the same components, circuitry, and configuration as UE 102 from FIG. 2B. However, any of the UEs in FIG. 1B may have components, circuitry, and configuration that differ from UE 102, in other examples.

UE 102 is any fixed, mobile, or portable equipment that performs the functions described herein. The various functions and operations of the blocks described with reference to UE 102 may be implemented in any number of devices, circuits, or elements. Two or more of the functional blocks may be integrated in a single device, and the functions described as performed in any single device may be implemented over several devices.

Controller 216 includes any combination of hardware, software, and/or firmware for executing the functions described herein as well as facilitating the overall functionality of a user equipment device. An example of a suitable controller 216 includes software code running on a microprocessor or processor arrangement connected to memory. Transmitter 218 includes electronics configured to transmit wireless signals. In some situations, the transmitter 218 may include multiple transmitters. Receiver 214 includes electronics configured to receive wireless signals. In some situations, receiver 214 may include multiple receivers. Receiver 214 and transmitter 218 receive and transmit signals, respectively, through antenna 212. Antenna 212 may include separate transmit and receive antennas. In some circumstances, antenna 212 may include multiple transmit and receive antennas.

Transmitter 218 and receiver 214 in the example of FIG. 2B perform radio frequency (RF) processing including modulation and demodulation. Receiver 214, therefore, may include components such as low noise amplifiers (LNAs) and filters. Transmitter 218 may include filters and amplifiers. Other components may include isolators, matching circuits, and other RF components. These components in combination or cooperation with other components perform the user equipment device functions. The required components may depend on the particular functionality required by the user equipment device.

Transmitter 218 includes a modulator (not shown), and receiver 214 includes a demodulator (not shown). The modulator can apply any one of a plurality of modulation orders to modulate the signals to be transmitted by transmitter 218. The demodulator demodulates received signals, in accordance with one of a plurality of modulation orders.

Sensor 220 is a camera in the example of FIG. 2B. However, in other examples, sensor 220 may be one or more of the following: a camera, lidar, radar, and ultrasound. In other examples, a sensor 220 could be a receiver configured to receive a beacon signal transmitted by another UE in a particular frequency or other known communication resource. In further examples, sensor 220 is a receiver configured to receive V2V signals. In still further examples, sensor 220 is configured to detect signals that do not require decoding. Any suitable sensor may be used in UE 102 to sense the environment around UE 102 and to sense other vehicles.

For the example of FIG. 1B, UE 1, 102, is located in an Advanced Driver Assistance Systems (ADAS) enabled vehicle. UE 1, 102, utilizes its sensor 220 to determine, without receiving communication signals, a presence and/or location of UE 2, 104; UE 3, 106; and object 110, which is located between UE 2, 104, and UE 3, 106. In the example of FIG. 1B, object 110 is a building. However, object 110 may be a geographic formation (e.g., hill/mountain) or any structure/object that interferes with communication signal transmission, in other examples.

Controller 216 of UE 1, 102 is coupled to sensor 220 and is configured to determine, based at least partially on output from sensor 220, a likelihood that object 110 will interfere with communication signal transmission between UE 2, 104, and UE 3, 106. In some examples, controller 216 of UE 1, 102 uses an Artificial Intelligence (AI) algorithm to identify the UEs that could be potential hidden-nodes, relative to each other. Thus, in these examples, the determined likelihood is a calculated value that is output from the AI algorithm and reflects the likelihood that object 110 will interfere with communication signal transmission between UE 2, 104 and UE 3, 106.

Transmitter 218 of UE 1, 102 is configured to transmit, to UE 3, 106, a message that results in UE 3, 106 using communication resources for transmission in a manner that will at least reduce interference with transmissions by UE 2, 104. In some examples, the message transmitted by transmitter 218 may be an indicator. In further examples, the message identifies communication resources reserved by UE 2, 104 for transmission. In response to receiving the message, UE 3, 106 may refrain from using resources identified in the message, may transmit communication signals with a lower transmission power, may transmit communication signals with a different code, or some combination of the foregoing.

In some examples, transmitter 218 of UE 1, 102 is configured to broadcast the message such that the message can be received at least by UE 2, 104 and UE 3, 106. In further examples, transmitter 218 transmits the message when the previously determined likelihood of interference is above a threshold, is within a range of values associated with a particular likelihood of interference, is at least approximately equivalent to a previously determined likelihood of interference that was associated with a situation in which interference occurred in the past, and/or is at least approximately equivalent to a likelihood of interference value that was contained in a set of training data utilized to train the AI algorithm used by controller 216 of UE 1, 102.

In other examples, controller 216 of UE 1, 102 is further configured to determine that UE 2, 104 will transmit a communication signal, and transmitter 218 of UE 1, 102 is further configured to transmit the message to UE 3, 106 in response to controller 216 determining that UE 2, 104 will transmit the communication signal. For example, if UE 1, 102 has the knowledge that UE 2, 104 has reserved a particular communication resource or if another device (e.g., a gNB or another UE) has scheduled a particular communication resource for UE 2, 104, then controller 216 of UE 1, 102 may make the determination that UE 2, 104 will transmit a communication signal.

In the examples in which UE 1, 102 obtains the knowledge that UE 2, 104 has reserved a particular communication resource, receiver 214 of UE 1, 102 is configured to receive a resource reservation signal. In some cases, the resource reservation signal is received from UE 2, 104. In other cases, the resource reservation signal is received from another device (e.g., a gNB or another UE) that has scheduled the communication resource for UE 2, 104. The resource reservation signal indicates that UE 2, 104 will transmit the communication signal using a particular transmission resource, and controller 216 of UE 1, 102 is configured to predict that UE 2, 104 will transmit a communication signal based on the receipt of the resource reservation signal.

In still further examples, receiver 214 of UE 1, 102 is configured to receive a resource reservation signal from another device (e.g., a gNB or another UE). The resource reservation signal indicates that the other device that transmitted the resource reservation signal will transmit a communication signal using a transmission resource, and controller 216 of UE 1, 102 is configured to determine that the other device will transmit the communication signal based on the receipt of the resource reservation signal.

Some of the foregoing examples describe UE 1, 102 detecting a potential hidden-node scenario (e.g., between UE 2, 104 and UE 3, 106) and informing the hidden-node UEs to reserve orthogonal resources for their next SL transmission. If the UE 1, 102 is already in communication with one of the potential hidden-node UEs (e.g., UE 2, 104), UE 1, 102 is aware of the other UE's transmit resources. Based on this knowledge, UE 1, 102 can forward the other UE's resource reservation information to the other potential hidden-node UE (e.g., UE 3, 106).

However, if more than one pair of potential hidden-node UEs are identified by UE 1, 102, it can become inefficient for UE 1, 102 to transmit multiple forwarding transmissions. Thus, in some examples, UE 1, 102 broadcasts a Neighbor List (NL) message containing the heading-direction of each of the identified hidden-node UEs. The NL message broadcast is an implicit indication of the hidden-node situation to UE 2, 104 and UE 3, 106.

Sending each hidden-node UE's heading-direction in the NL message increases the overhead since it requires several bits to represent this information. Thus, in other examples, the AI algorithm can be configured to generate an “intelligent” NL message. For example, the NL message does not need to list UEs that have a low likelihood of causing interference as a hidden-node UE (e.g., UEs that are moving away from the intersection or UEs that are too far away from the intersection to cause interference). After deleting these non-interfering UEs from the NL, the remaining UEs are assigned a resource pool or group based on their heading-direction and/or location.

In the example shown in FIG. 1B, UE 1, 102 can broadcast an NL message indicating (e.g., with a destination identifier in the NL message) that UE 2, 104 is assigned to resource pool A or group A because it is moving in a first direction of travel 103. The NL message also indicates that UE 3, 106 and UE 4, 108 are assigned to resource pool B or group B because both UEs are moving in the same second direction of travel 107. The assignment of UEs to a resource pool or group based on their respective heading/direction of travel helps to generate a concise NL format, reducing the overall signaling overhead. However, the assignments are just a recommendation by UE 1, 102 to the UEs that receive the NL message. Each of the NL message-receiving UEs take the suggested assignment information into account when reserving resources for their next SL transmission and may choose whether or not to transmit their next SL transmission using the resource pool to which they were assigned, as indicated in the most recently received NL message.

In some instances, it is possible that multiple UEs may approach the same intersection and each broadcast an NL message. Thus, in some examples, excessive NL message broadcasting can be avoided when only one UE within a region is allowed to do periodic NL message broadcasting. For example, the AI algorithm can be further configured to determine whether a UE should broadcast the NL message in the presence of another neighboring UE that is already broadcasting an NL message.

If a non-NL message broadcasting UE finds additional hidden-node UEs not included in the previous NL message broadcast only then that UE is allowed to broadcast an NL message, as well. In some examples, the additional broadcast just contains the additional hidden-node UEs that were not included in the previous NL message broadcast. In other examples, if a predetermined/preconfigured amount of time has passed since the previous NL message was broadcasted, the additional broadcast could include all of the hidden-node UEs from the previous NL message as well as the additional hidden-node UEs that were not included in the previous NL message broadcast. However, if all of the hidden-node UEs are included in the additional broadcast, the previous NL message broadcasting UE may be configured to cease transmitting the NL message.

Given the foregoing description of the NL message, in some examples, the message that UE 1, 102 transmits to UE 3, 106, which results in UE 3, 106 using communication resources for transmission in a manner that will at least reduce interference with transmissions by UE 2, 104, is an NL message broadcasted by transmitter 218 of UE 1, 102. In these examples, the NL message identifies UE 2, 104 and UE 3, 106 as neighboring UE devices. In other examples, the NL message may also identify a first direction of travel 103 of UE 2, 104 and a second direction of travel 107 of UE 3, 106.

As mentioned above, in some examples, the NL message identifies an assignment of UE 2, 104 to a first group (e.g., group A) and identifies an assignment of UE 3, 106 to a second group (e.g., group B). In further examples, controller 216 of UE 1, 102 is configured to assign UE devices traveling in a first direction of travel 103 to the first group and assign UE devices traveling in a second direction of travel 107 to the second group. In other examples, controller 216 of UE 1, 102 is configured to assign UE devices located in a first area to the first group and assign UE devices located in a second area to the second group. In these examples, the first area and the second area can be any areas that are sufficiently defined to enable the UEs to determine a likelihood of a potential hidden-node scenario.

In still further examples, the NL message identifies a first communication resource pool (e.g., resource pool A) for transmission by UE devices assigned to the first group and a second communication resource pool (e.g., resource pool B) for transmission by UE devices assigned to the second group. In response to receiving the NL message that identifies the first communication resource pool for transmission by UE devices assigned to the first group and a second communication resource pool for transmission by UE devices assigned to the second group, UE 3, 106 may choose to transmit, based at least partially on the NL message, a sidelink transmission using communication resources selected from the communication resource pool that corresponds with the group to which UE 3, 106 was assigned.

In some examples, transmitter 218 of UE 1, 102 is further configured to periodically broadcast the NL message. In further examples, transmitter 218 of UE 1, 102 is configured to refrain from broadcasting a current version of the NL message if the current version of the NL message is the same as a previous version of the NL message. In still further examples, transmitter 218 of UE 1, 102 is configured to refrain from broadcasting a current version of the NL message if the current version of the NL message is a subset of a previous version of the NL message. In some examples, UE 1, 102 is configured to broadcast the NL message upon the expiration of a timer, even if the current version of the NL message is a partial or complete duplicate of a previous version of the NL message.

Although NL message-carrying SL transmissions by the UEs have low overhead and less delay, it may be beneficial, in other examples, to offload such non-safety message transmissions from the V2V band to the cellular band, resulting in less congestion of the V2V band, which makes more bandwidth available for important safety message SL transmissions. Following are several examples in which the network (e.g., gNBs) can be utilized to assist in avoiding transmission collisions in the V2V communications.

In some examples, a base station (e.g., gNB) employs a broadcast technology such as the Multimedia Broadcast Multicast Service (MBMS) to relay the hidden-node information to the neighboring UE devices. In addition to V2X band offloading and lower deployment cost by avoiding the need to install gNB/RSUs at every intersection, the MBMS method has much less delay compared to periodically broadcasting a System Information Block (SIB) message.

The MBMS procedure achieves reduced delay because the MBMS subscribed UEs are able to listen to the continuously transmitted MBMS Notification Indicator (MNI) to check if the UE should receive MBMS Control Channel (MCCH) in the next modification period. The MCCH is transmitted on a fixed schedule depending upon the service type. This schedule is provided in the SIB message over the broadcast channel. The subscribed UE(s) receive the MBMS Traffic Channel (MTCH) after decoding the schedule information in the corresponding MCCH. This procedure allows the gNB to be able to transmit an MTCH as soon it receives the hidden-node information from the UE that has recently detected a hidden-node situation.

After receiving the MBMS data from the gNB, all the regional UEs take the received hidden node information into account for the transmit resource (re-)selection. For the example shown in FIG. 1C, UE 2, 104 and UE 3, 106 would select orthogonal sets of resources for their next SL transmission to avoid the hidden-node situation described above. The gNB broadcasts the resource assignment preference to the UEs, and the UEs take this information into account before (re-)selecting their SL transmit resources.

As will be described more fully below in connection with FIG. 10, UE 1, 102 uses the on-board AI technology to find UE 3, 106 to be a potential hidden-node with respect to UE 2, 104. UE 1, 102 also determines there is a direct line-of-sight between UE 2, 104 and UE 4, 108; therefore, UE 4, 108 is a potential hidden-node victim. Although the examples herein describe the general signaling exchange between the UEs and the base station, there are various options for the contents of (1) the report sent from the hidden-node reporting UE (e.g., UE 1, 102) to the gNB, and (2) the message sent from the gNB in the MBMS broadcast to the one or more UEs.

For example, FIG. 1C shows a block diagram of a system in which a first base station receives at least one report based on data acquired by at least one non-communication sensor. Based on the at least one report, the base station transmits a message to a UE device that results in the UE device refraining from using communication resources that will interfere with transmissions by other UE devices.

In the interest of clarity and brevity, only one infrastructure communication node (e.g., base station 112) is shown in FIG. 1C. However, in other examples, any suitable number of infrastructure communication nodes may be utilized to receive reports from the UEs and to transmit messages to the UEs. For the example shown in FIG. 1C, base station 112, sometimes referred to as a gNodeB or gNB, can receive uplink messages from UE devices and can transmit downlink messages to the UE devices. In other examples, the infrastructure communication node is a road side unit (RSU).

Base station 112 is connected to the network through a backhaul (not shown) in accordance with known techniques. As shown in FIG. 2A, base station 112 comprises controller 204, transmitter 206, and receiver 208, as well as other electronics, hardware, and code. Base station 112 is any fixed, mobile, or portable equipment that performs the functions described herein. The various functions and operations of the blocks described with reference to base station 112 may be implemented in any number of devices, circuits, or elements. Two or more of the functional blocks may be integrated in a single device, and the functions described as performed in any single device may be implemented over several devices.

For the example shown in FIG. 2A, base station 112 may be a fixed device or apparatus that is installed at a particular location at the time of system deployment. Examples of such equipment include fixed base stations or fixed transceiver stations. In some situations, base station 112 may be mobile equipment that is temporarily installed at a particular location. Some examples of such equipment include mobile transceiver stations that may include power generating equipment such as electric generators, solar panels, and/or batteries. Larger and heavier versions of such equipment may be transported by trailer. In still other situations, base station 112 may be a portable device that is not fixed to any particular location. Accordingly, base station 112 may be a portable user device such as a UE device in some circumstances.

Controller 204 includes any combination of hardware, software, and/or firmware for executing the functions described herein as well as facilitating the overall functionality of base station 112. An example of a suitable controller 204 includes code running on a microprocessor or processor arrangement connected to memory. Transmitter 206 includes electronics configured to transmit wireless signals. In some situations, transmitter 206 may include multiple transmitters. Receiver 208 includes electronics configured to receive wireless signals. In some situations, receiver 208 may include multiple receivers. Receiver 208 and transmitter 206 receive and transmit signals, respectively, through antenna 210. Antenna 210 may include separate transmit and receive antennas. In some circumstances, antenna 210 may include multiple transmit and receive antennas.

Transmitter 206 and receiver 208 in the example of FIG. 2A perform radio frequency (RF) processing including modulation and demodulation. Receiver 208, therefore, may include components such as low noise amplifiers (LNAs) and filters. Transmitter 206 may include filters and amplifiers. Other components may include isolators, matching circuits, and other RF components. These components in combination or cooperation with other components perform the base station functions. The required components may depend on the particular functionality required by the base station.

Transmitter 206 includes a modulator (not shown), and receiver 208 includes a demodulator (not shown). The modulator modulates the signals that will be transmitted and can apply any one of a plurality of modulation orders. The demodulator demodulates any uplink signals received at base station 112 in accordance with one of a plurality of modulation orders.

In operation, base station 112 receives, via antenna 210 and receiver 208, at least one report based on data acquired by at least one non-communication sensor of one or more UEs. As mentioned above, examples of a non-communication sensor could include cameras, radar, and/or lidar incorporated into vehicle UE device UE 1, 102. Of course, any other suitable non-communication sensor could be used, in other examples.

The at least one report contains first heading information pertaining to UE 1, 102, first communication resources reserved by UE 1, 102, and second communication resources reserved by UE 2, 104, which has a heading that corresponds with the first heading information. In the example shown in FIG. 1C, UE 1, 102 and UE 2, 104 have the same heading since they are both traveling in the same direction 103. In some examples, the at least one report also contains one or more of the following: first location information pertaining to UE 1, 102, and second location information pertaining to UE 2, 104.

In the example shown in FIG. 1C, the entirety of the contents of the at least one report is received at base station 112 via uplink signal 114 from UE 1, 102. In other examples, the at least one report comprises a first report received from UE 1, 102 and a second report received from UE 2, 104. In these examples, the first report contains the first heading information pertaining to UE 1, 102 and the first communication resources reserved by UE 1, 102, and the second report contains second heading information pertaining to UE 2, 104 and the second communication resources reserved by UE 2, 104.

Upon receipt of the at least one report, base station 112 transmits a message, based at least partially on the at least one report, to UE 3, 106. In the example shown in FIG. 1C, the message is transmitted via downlink signal 116 to UE 3, 106, which has a heading that does not correspond with the heading information that pertains to UE 1, 102. As will be discussed more fully below, the transmittal of the message results in UE 3, 106 refraining from using communication resources for transmission that will interfere with transmissions by UE 1, 102 and UE 2, 104.

In some examples, base station 112 transmits, via transmitter 206 and antenna 210, the message in a Multimedia Broadcast Multicast Service (MBMS) broadcast transmission. In further examples, base station 112 transmits the MBMS broadcast transmission to a region surrounding an intersection near which UE 1, 102 and UE 2, 104 are located. In still further examples, base station 112 transmits the MBMS broadcast transmission, via a beam, to a specific area within the region surrounding the intersection. In other examples, base station 112 transmits the MBMS broadcast transmission within one of a plurality of cells located within the region surrounding the intersection.

As mentioned above, UE 3, 106 receives the message from base station 112. Upon receipt of the message, controller 216 of UE 3, 106 is configured to refrain from using communication resources for transmission that will interfere with transmissions by UE 1, 102 and UE 2, 104. More specifically, controller 216 of UE 3, 106 is further configured, in some examples, to determine that at least one of the first communication resources reserved by UE 1, 102 and the second communication resources reserved by UE 2, 104 at least partially overlap with third communication resources reserved by UE 3, 106 for an upcoming transmission. Upon such a determination, controller 216 of UE 3, 106 is configured to select fourth communication resources to reserve for the upcoming transmission by UE 3, 106 instead of the previously selected third communication resources. Although the preceding examples describe how UE 3, 106 selects new communication resources if there is an overlap with communication resources reserved by other UE devices, UE 3, 106 is not obligated to select new communication resources in the event of a potential overlap in communication resources, in other examples.

The foregoing examples describe base station 112 advantageously employing a broadcast technology such as MBMS to relay the hidden-node information to the neighboring UEs. The MBMS transmission may be based on broadcast/groupcast or multicast, depending on whether the targeted UEs for the MBMS reception are in RRC_IDLE/RRC_INACTIVE or RRC_CONNECTED states, which are states in the Radio Resource Control (RRC) protocol. Currently, MBMS multicast is intended for UEs in an RRC_CONNECTED state. MBMS transmission with multicast typically has better robustness, especially as UEs move from cell to cell; whereas, MBMS using broadcast means tend to be based on best-effort.

In order to reduce the signaling overhead and avoid sending UE identifiers (e.g., license plate information), the hidden-nodes reporting UE (e.g., UE 1, 102) reports to the gNB its own heading and/or location and the list of resource(s) reserved for its own transmissions and resources recently reserved by other transmitting UEs. Referring again to FIG. 1A, assume that UE 1, 102 and UE 2, 104 reserved resources X and Y, respectively, for SL data communications. Then ADAS/AI capable UE 1, 102 determines UE 3, 106 and UE 4, 108 to be the potential hidden-node and the hidden-node victim, respectively. The detection of the hidden-node triggers UE 1, 102 to send a report to a gNB (shown in FIG. 1C). In this report, UE 1, 102 sends its own heading and/or location information and the list of resources X and Y as reserved SL transmission resources.

The gNB receives the report and relays the same information via MBMS broadcast. The MBMS broadcast receiving UEs (e.g., UE 3, 106) view the listed resources X and Y as the non-preferred or blocked resources by the north-south heading vehicles. Before receiving the MBMS broadcast the UEs may not have yet detected any SL transmission in those resources (e.g., X and Y) and assumed those to be available for their own SL transmissions. Thus, if the listed resources overlap with the MBMS broadcast receiving UE's own reserved transmission resources, then the MBMS broadcast receiving UEs could decide to do a resource reselection to reserve other resources for the next SL transmission. In the above example, after receiving the above MBMS broadcast UE 3, 106 observes the resources X and Y are reserved by north-south heading vehicles that could be hidden since UE 3, 106 is heading east-west on a different street. As a result, UE 3, 106 decides to do a resource reselection if it has reserved either X or Y for its next SL transmission. In this manner, the system functions to advantageously reduce the likelihood of a data transmission collision before it occurs.

In other examples, a less capable ADAS-enabled vehicle reports the heading and/or location of the hidden-node(s) to the base station but does not report an identifier of the vehicle in which the hidden-node UE is located. After receiving the heading/location information, the gNB assigns resources (or pools) based on the reported heading/location information and broadcasts the assignments to the neighboring UEs. FIG. 1D is a block diagram of an example of a system in which a base station receives a report based on data acquired by at least one non-communication sensor and assigns communication resources to UE devices based on the report.

More specifically, base station 112 of FIG. 1D receives, via its antenna 210 and receiver 208, a first report from UE 1, 102 in uplink signal 114. The first report is based on data acquired by at least one non-communication sensor 220 of UE 1, 102. As described above, sensor 220 is configured to sense, without receiving communication signals, a heading of UE 2, 104 and a heading of UE 3, 106. The first report contains first heading information pertaining to UE 2, 104 and second heading information pertaining to UE 3, 106. In other examples, the first report further contains first location information pertaining to UE 2, 104 and second location information pertaining to UE 3, 106.

Base station 112 utilizes its controller 204 to assign first communication resources to UE 2, 104 based at least partially on the first heading information and second communication resources to UE 3, 106 based at least partially on the second heading information. In the examples in which the first report also contains location information, controller 204 is further configured to assign the first communication resources to UE 2, 104 based at least partially on the first heading and location information and to assign the second communication resources to UE 3, 106 based at least partially on the second heading and location information.

Base station 112 transmits, via its transmitter 206 and antenna 210, to UE 2, 104 and UE 3, 106, one or more messages that collectively identify assignment of the first communication resources and assignment of the second communication resources. Thus, in some examples, one message may identify assignment of the first communication resources to UE 2, 104 and assignment of the second communication resources to UE 3, 106. In other examples, a first message identifies assignment of the first communication resources to UE 2, 104, and a second message identifies assignment of the second communication resources to UE 3, 106.

In some examples, transmitter 206 of base station 112 is further configured to transmit the one or more messages in a Multimedia Broadcast Multicast Service (MBMS) broadcast transmission. In other examples, transmitter 206 of base station 112 is configured to transmit, via dedicated signaling, a first message to UE 2, 104 that identifies assignment of the first communication resources, and transmitter 206 of base station 112 is also configured to transmit, via dedicated signaling, a second message to UE 3, 106 that identifies assignment of the second communication resources.

UE 2, 104 receives, via its antenna 212 and receiver 214, from base station 112, the one or more messages that collectively identify assignment of first communication resources and assignment of second communication resources. The first communication resources assigned to UE 2, 104 are based at least partially on first heading information pertaining to UE 2, 104 received at base station 112, and the second communication resources assigned to UE 3, 106 are based at least partially on second heading information pertaining to UE 3, 106 received at base station 112. UE 2, 104 utilizes its controller 216 to refrain from using the second communication resources for transmission.

In these examples, it is assumed that the MBMS broadcast coverage is limited to the region surrounding the intersection. Thus, the gNB could use specific beams to broadcast MBMS to target a specific area, or the network could deploy multiple smaller cells in a region such that the MBMS is only broadcasted in one of the smaller cells to target a region.

In examples involving more capable ADAS-enabled vehicles, the first report sent by UE 1, 102 to base station 112 also contains, beside the first heading information of UE 2, 104 and the second heading information of UE 3, 106, a first identifier associated with a vehicle in which UE 2, 104 is located and a second identifier associated with a vehicle in which UE 3, 106 is located. In some of these further examples, the identifier is license plate information of the vehicle, which may include alphanumeric characters, symbols, etc. Controller 204 of base station 112 maps each license plate listed in the first report to a UE identifier and then uniquely notifies the relevant vehicle UE, either via MBMS broadcast or dedicated signaling.

The amount of post-processing performed by base station 112 depends upon the type of information sent by the hidden-node reporting UE. As discussed above in connection with less capable ADAS-enabled vehicles, UE 1, 102 may be unable to determine the license plate information for the hidden-node UEs (e.g., for UE 2, 104 and UE 3, 106). So, in these examples, base station 112 broadcasts a general resource assignment based on the heading of the vehicles.

In examples involving more capable ADAS-enabled vehicles, UE 1, 102 sends the hidden-node UE's license plate information with the heading information so base station 112 can uniquely notify the hidden-node UEs to perform a resource reselection or to assign a specific SL transmit resource to each UE. However, it is possible the identified hidden-node UE is not interested in SL transmission. Therefore, in some examples, the base station's resource assignment has a time-expiration, and/or the hidden-node UE could release the assigned resource by sending a message back to the base station.

Thus, in some examples, the assignment of the first communication resources automatically expires after a first time period, and the assignment of the second communication resources automatically expires after a second time period. In other examples, receiver 208 of base station 112 is further configured to receive a release message from UE 2, 104 requesting release of the first communication resources.

FIG. 1D also depicts a situation in which multiple UEs may send hidden-node reports to the gNB. More specifically, for the example shown in FIG. 1D, the hidden-node report sent by UE 1, 102 would include the possibility that UE 2, 104 and UE 3, 106 are hidden nodes relative to each other, and the hidden-node report sent (in uplink signal 124) by UE 5, 118 would include UE 1, 102 and UE 6, 122 as possible hidden nodes relative to each other due to the location of object 120. The hidden-node report sent by UE 5, 118 would include heading information pertaining to UE 1, 102 and heading information pertaining to UE 6, 122, in some examples.

Although UE 1, 102 can sense that UE 2, 104 and UE 3, 106 may be hidden nodes to one another, UE 1, 102 does not know whether UE 2, 104 or UE 3, 106 intends to transmit a sidelink transmission. This is also the same for the hidden-node report of UE 5, 118 in that it is unknown whether UE 1, 102 and UE 6, 122 intend to transmit a sidelink transmission.

Therefore, in these examples, when UE 1, 102 sends its hidden-node report to base station 112, UE 1, 102 also sends a 1-bit flag (e.g., in the Media Access Control header) in the hidden-node report if UE 1, 102 intends to transmit a SL transmission. Thus, if base station 112 also receives a hidden-node report from UE 5, 118 indicating that UE 1, 102 may be a hidden node, then base station 112 can determine, based on the two hidden-node reports, that UE 1, 102 is a potential hidden node (based on the hidden-node report from UE 5, 118) and that UE 1, 102 intends to transmit a SL transmission (based on the hidden-node report from UE 1, 102). By piggy backing the 1-bit flag as part of the hidden-node report, there is no need to send additional signaling messages to base station 112 in order to reduce signaling load. There are several alternatives for how base station 112 responds once the hidden-node report with SL transmission indication is received.

In the first alternative, base station 112 recommends that UE 1, 102 uses a dedicated SL resource instead of using Mode 2 resources. More specifically, base station 112 transmits, via its transmitter 206 and antenna 210, a dedicated sidelink transmission resource to UE 1, 102 to be used for sidelink transmission. In this manner, UE 1, 102 will not cause transmission collisions with other nearby UEs, and the dedicated resources will not go wasted since UE 1, 102 has already indicated its intention to transmit on the SL. In some examples, the dedicated resource may be a subset of the original Mode 2 resource pool, and in these cases, base station 112 will broadcast MBMS (or SIB messages) containing the updated Mode 2 resource pool that excludes those resources dedicated to UE 1, 102.

In the second alternative, base station 112 informs UE 1, 102 to use a particular exceptional resource pool specifically allocated for hidden nodes. More specifically, base station 112 transmits, to UE 1, 102, a hidden node resource assignment from a pool of resources (e.g., exceptional resource pool) allocated for hidden nodes. There may be multiple exceptional resources allocated depending on the likelihood of a hidden node in a particular intersection. It may be assumed that each hidden node that intends to transmit on the SL would be temporarily allocated with one of the exceptional resource pools, in some examples. Base station 112 may optionally inform UE 1, 102 that this usage of the pool is only valid within a configured time window, in some examples.

In some examples of this alternative, base station 112 broadcasts MBMS (or SIB messages) containing the updated Mode 2 resource pool that excludes those exceptional resources pools. More specifically, in these examples, the hidden node resource assignment is a subset of a Mode 2 resource pool, and in these cases, base station 112 will broadcast an updated Mode 2 resource pool that excludes the hidden node resource assignment.

In the third alternative, base station 112 simply relays, via MBMS, the received information that was provided in the two hidden-node reports from UE 1, 102 and UE 5, 118. More specifically, transmitter 206 of base station 112 is configured to broadcast a message, based at least partially on the first report and the second report. The UEs receive the relayed information from base station 112 and take it into consideration when they select their respective SL transmit resources. In particular, the MBMS may contain a UE identifier of a potential hidden node that has indicated its intent to transmit on the SL. Thus, the message broadcasted by base station 112 results in the UE devices that receive the message refraining from using communication resources for transmission that will interfere with sidelink transmissions by UE 1, 102 when the indicator indicates that UE 1, 102 intends to transmit a sidelink transmission.

FIG. 3 is a flowchart of an example of a method in which a first base station receives a first report based on data acquired by at least one non-communication sensor of a first UE device. Based on the first report, the base station assigns communication resources to a second UE device and a third UE device and transmits the assignments to the second and third UE devices. The method 300 begins at step 302 with receiving, at a base station from a first UE device, a first report based on data acquired by at least one non-communication sensor. The first report contains first heading information pertaining to a second UE device and second heading information pertaining to a third UE device. At step 304, the base station assigns first communication resources to the second UE device based at least partially on the first heading information. At step 306, the base station assigns second communication resources to the third UE device based at least partially on the second heading information. At step 308, the base station transmits, to the second UE device and the third UE device, one or more messages that collectively identify assignment of the first communication resources and assignment of the second communication resources. In other examples, one or more of the steps of method 300 may be omitted, combined, performed in parallel, or performed in a different order than that described herein or shown in FIG. 3. In still further examples, additional steps may be added to method 300 that are not explicitly described in connection with the example shown in FIG. 3.

Clearly, other embodiments and modifications of this invention will occur readily to those of ordinary skill in the art in view of these teachings. The above description is illustrative and not restrictive. This invention is to be limited only by the following claims, which include all such embodiments and modifications when viewed in conjunction with the above specification and accompanying drawings. The scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the appended claims along with their full scope of equivalents.

Claims

1. A first base station comprising: a receiver configured to receive, from a first user equipment (UE) device, a first report based on data acquired by at least one non-communication sensor, the first report containing: first heading information pertaining to a second UE device, andsecond heading information pertaining to a third UE device;a controller configured to: assign first communication resources to the second UE device based at least partially on the first heading information, andassign second communication resources to the third UE device based at least partially on the second heading information; anda transmitter configured to transmit, to the second UE device and the third UE device, one or more messages that collectively identify assignment of the first communication resources and assignment of the second communication resources.

2. The first base station of claim 1, wherein the transmitter is further configured to transmit the one or more messages in a Multimedia Broadcast Multicast Service (MBMS) broadcast transmission.

3. The first base station of claim 1, wherein the first report contains first location information pertaining to the second UE device and second location information pertaining to the third UE device, and the controller is further configured to: assign the first communication resources to the second UE device based at least partially on the first heading and location information, andassign the second communication resources to the third UE device based at least partially on the second heading and location information.

4. The first base station of claim 1, wherein the first report further contains a first identifier associated with a vehicle in which the second UE device is located and a second identifier associated with a vehicle in which the third UE device is located.

5. The first base station of claim 4, wherein the transmitter is further configured to: transmit, to the second UE device via dedicated signaling, a first message that identifies assignment of the first communication resources, andtransmit, to the third UE device via dedicated signaling, a second message that identifies assignment of the second communication resources.

6. The first base station of claim 1, wherein the assignment of the first communication resources automatically expires after a first time period.

7. The first base station of claim 1, wherein the receiver is further configured to receive, from the second UE device, a release message requesting release of the first communication resources.

8. The first base station of claim 1, wherein the receiver is further configured to receive, from a fourth UE device, a second report containing: third heading information pertaining to the first UE device, andfourth heading information pertaining to a fifth UE device,the first report further containing an indicator that indicates whether the first UE device intends to transmit a sidelink transmission.

9. The first base station of claim 8, wherein the indicator is a 1-bit flag.

10. The first base station of claim 8, wherein the transmitter is further configured to transmit, to the first UE device, a dedicated sidelink transmission resource to be used for sidelink transmission.

11. The first base station of claim 10, wherein the dedicated sidelink transmission resource is a subset of a Mode 2 resource pool, the transmitter further configured to broadcast an updated Mode 2 resource pool that excludes the dedicated sidelink transmission resource.

12. The first base station of claim 8, wherein the transmitter is further configured to transmit, to the first UE device, a hidden node resource assignment from a pool of resources allocated for hidden nodes.

13. The first base station of claim 12, wherein the hidden node resource assignment is a subset of a Mode 2 resource pool, the transmitter further configured to broadcast an updated Mode 2 resource pool that excludes the hidden node resource assignment.

14. The first base station of claim 8, wherein the transmitter is further configured to broadcast a message, based at least partially on the first report and the second report, wherein broadcasting the message results in UE devices that receive the message refraining from using communication resources for transmission that will interfere with sidelink transmissions by the first UE device when the indicator indicates that the first UE device intends to transmit a sidelink transmission.

15. A first user equipment (UE) device comprising: a receiver configured to receive, from a first base station, one or more messages that collectively identify assignment of first communication resources and assignment of second communication resources, the first communication resources assigned to the first UE device based at least partially on first heading information pertaining to the first UE device received at the first base station, the second communication resources assigned to a second UE device based at least partially on second heading information pertaining to the second UE device received at the first base station; anda controller configured to refrain from using the second communication resources for transmission.

16. The first UE device of claim 15, wherein the receiver is further configured to receive the one or more messages in a Multimedia Broadcast Multicast Service (MBMS) broadcast transmission.

17. The first UE device of claim 15, wherein the receiver is further configured to receive, from the first base station via dedicated signaling, a first message that identifies assignment of the first communication resources.

18. The first UE device of claim 15, wherein the first communication resources are assigned to the first UE device based at least partially on first heading and location information pertaining to the first UE device received at the first base station, the second communication resources assigned to the second UE device based at least partially on second heading and location information pertaining to the second UE device received at the first base station.

19. The first UE device of claim 15, further comprising: a transmitter configured to transmit, to the first base station, a release message requesting release of the first communication resources.

20. A first user equipment (UE) device comprising: at least one sensor configured to sense, without receiving communication signals, a heading of a second UE device and a heading of a third UE device; anda transmitter configured to transmit, to a first base station, a first report containing: first heading information pertaining to the second UE device, andsecond heading information pertaining to the third UE device.

21. The first UE device of claim 20, wherein the first report further contains first location information pertaining to the second UE device and second location information pertaining to the third UE device.

22. The first UE device of claim 20, wherein the first report further contains a first identifier associated with a vehicle in which the second UE device is located and a second identifier associated with a vehicle in which the third UE device is located.

23. The first UE device of claim 20, wherein the first report further contains an indicator that indicates whether the first UE device intends to transmit a sidelink transmission.

24. The first UE device of claim 23, wherein the indicator is a 1-bit flag.

25. The first UE device of claim 23, wherein the receiver is further configured to receive, from the first base station, a dedicated sidelink transmission resource to be used for sidelink transmission.

26. The first UE device of claim 25, wherein the dedicated sidelink transmission resource is a subset of a Mode 2 resource pool, the receiver further configured to receive a broadcast of an updated Mode 2 resource pool that excludes the dedicated sidelink transmission resource.

27. The first UE device of claim 23, wherein the receiver is further configured to receive, from the first base station, a hidden node resource assignment from a pool of resources allocated for hidden nodes.

28. The first UE device of claim 27, wherein the hidden node resource assignment is a subset of a Mode 2 resource pool, the receiver further configured to receive a broadcast an updated Mode 2 resource pool that excludes the hidden node resource assignment.