Patent Application
20230291513
The present disclosure generally relates to communication networks, and more specifically, to a method and apparatus for carrier control.
This section introduces aspects that may facilitate a better understanding of the disclosure. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.
Communication service providers and network operators have been continually facing challenges to deliver value and convenience to consumers by, for example, providing compelling network services and performance. With the rapid development of networking and communication technologies, wireless communication networks such as long term evolution (LTE)/fourth generation (4G) networks and new radio (NR)/fifth generation (5G) networks are expected to achieve high traffic capacity and end-user data rate with lower latency. In order to meet dramatically increasing network requirements, one interesting option for communication technique development is to support flexible network configuration, e.g., carrier aggregation (CA) with adaptive numerology. The term “numerology” may be used to refer to some parameters related to the radio resources for signal transmissions, such as subcarrier spacing (SCS), the length or duration of a cyclic prefix (CP), the length or duration of an orthogonal frequency division multiplexing (OFDM) symbol, the number of symbols contained in a time slot, the time slot duration, etc. Carrier combinations or CA with different numerologies may be supported to achieve potentially network performance gain by flexible radio resource configuration.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
Comparing to LTE numerology (e.g., SCS, symbol length, slot, etc.), one of outstanding differences in NR numerology is that a NR network may support multiple different types of SCS (e.g., 15 KHz, 30 KHz, 60 KHz, 120 KHz, etc.), while in an LTE network there may be only one type of SCS (e.g., 15 KHz). The NR network may also support carrier combinations such as CA with different numerologies to improve network throughput and cell coverage. However, application of CA with different numerologies may introduce extra transmission delay, e.g. larger hybrid automatic repeat request (HARQ) feedback delay in some scenarios. Therefore, it may be desirable to control carrier combinations or CA in a more efficient way.
Various embodiments of the present disclosure propose a solution for carrier control, which can enable a secondary cell (Scell) to be selected (e.g., for configuration/activation/scheduling, etc.) for a terminal device such as a user equipment (UE) adaptively, for example, according to HARQ latency related to numerologies of a primary cell (Pcell) and the Scell of the terminal device, so as to improve flexibility of CA configuration and enhance resource utilization without increasing transmission delay significantly.
It can be appreciated that selecting a Scell for a terminal device as described in this document may refer to configuring a Scell for a terminal device, activating a Scell configured for a terminal device, and/or scheduling a Scell activated for a terminal device. In addition, it also may be appreciated that one or more Scells may be selected for a terminal device according to different configurations.
According to a first aspect of the present disclosure, there is provided a method performed by a network node (e.g., a base station). The method comprises calculating first feedback latency of a terminal device with respect to the network node, based at least in part on a numerology of a candidate cell for the terminal device. In accordance with an exemplary embodiment, the method further comprises determining whether to select the candidate cell as a Scell of the terminal device, according to the first feedback latency.
In accordance with an exemplary embodiment, the first feedback latency may correspond to a carrier combination of the candidate cell and a Pcell of the terminal device.
In accordance with an exemplary embodiment, the first feedback latency may be further based at least in part on one or more of: a numerology of a Pcell of the terminal device; a frame pattern for the terminal device; and a capability of the terminal device.
In accordance with an exemplary embodiment, the calculation of the first feedback latency may comprise: estimating downlink channel processing time of the terminal device, according to the numerology of the candidate cell and a numerology of a Pcell of the terminal device; and calculating the first feedback latency according to the downlink channel processing time of the terminal device.
In accordance with an exemplary embodiment, the first feedback latency may be adjusted according to a frame pattern for the terminal device.
In accordance with an exemplary embodiment, the first feedback latency may be equal to a minimum number of slots from downlink scheduling of the terminal device by the network node to uplink feedback to the downlink scheduling by the terminal device.
In accordance with an exemplary embodiment, the candidate cell may be included in a cell list for the terminal device according to the first feedback latency.
In accordance with an exemplary embodiment, the network node may determine to select the candidate cell as the Scell of the terminal device, in response to the first feedback latency meeting one or more of:
In accordance with an exemplary embodiment, selecting the candidate cell as the Scell of the terminal device may comprise: configuring the candidate cell as the Scell of the terminal device.
In accordance with an exemplary embodiment, the candidate cell may be configured as the Scell of the terminal device according to one or more of:
In accordance with an exemplary embodiment, the candidate cell may be one of cells configured for the terminal device. In this case, selecting the candidate cell as the Scell of the terminal device may comprise: activating the candidate cell as the Scell of the terminal device.
In accordance with an exemplary embodiment, the candidate cell may be activated as the Scell of the terminal device according to one or more of:
In accordance with an exemplary embodiment, the candidate cell may be one of cells activated for the terminal device. In this case, selecting the candidate cell as the Scell of the terminal device may comprise: scheduling the candidate cell as the Scell of the terminal device.
In accordance with an exemplary embodiment, the candidate cell may be scheduled as the Scell of the terminal device according to one or more of:
In accordance with an exemplary embodiment, the method according to the first aspect of the present disclosure may further comprise: transmitting information about the Scell to the terminal device.
In accordance with an exemplary embodiment, the information about the Scell may be transmitted to the terminal device in one or more of:
In accordance with an exemplary embodiment, the method according to the first aspect of the present disclosure may further comprise: selecting one or more other candidate cells as Scells of the terminal device, according to feedback latencies of the terminal device which may be calculated based at least in part on numerologies of the one or more other candidate cells.
According to a second aspect of the present disclosure, there is provided an apparatus which may be implemented as a network node. The apparatus may comprise one or more processors and one or more memories comprising computer program codes. The one or more memories and the computer program codes may be configured to, with the one or more processors, cause the apparatus at least to calculate first feedback latency of a terminal device with respect to the network node, based at least in part on a numerology of a candidate cell for the terminal device. According to some exemplary embodiments, the one or more memories and the computer program codes may be configured to, with the one or more processors, cause the apparatus at least further to determine whether to select the candidate cell as a Scell of the terminal device, according to the first feedback latency.
In accordance with some exemplary embodiments, the one or more memories and the computer program codes may be configured to, with the one or more processors, cause the apparatus according to the second aspect of the present disclosure at least to perform any step of the method according to the first aspect of the present disclosure.
According to a third aspect of the present disclosure, there is provided a computer-readable medium having computer program codes embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to the first aspect of the present disclosure.
According to a fourth aspect of the present disclosure, there is provided an apparatus which may be implemented as a network node. The apparatus may comprise a calculating unit and a determining unit. In accordance with some exemplary embodiments, the calculating unit may be operable to carry out at least the calculating step of the method according to the first aspect of the present disclosure. The determining unit may be operable to carry out at least the determining step of the method according to the first aspect of the present disclosure.
According to a fifth aspect of the present disclosure, there is provided a method performed by a terminal device (e.g., a UE). The method comprises receiving information about a Scell of the terminal device from a network node. The Scell may be selected for the terminal device by the network node according to first feedback latency of the terminal device with respect to the network node. The first feedback latency may be based at least in part on a numerology of the Scell. In accordance with an exemplary embodiment, the method further comprises determining the Scell of the terminal device according to the received information.
In accordance with an exemplary embodiment, the information about the Scell described according to the fifth aspect of the present disclosure may correspond to the information about the Scell described according to the first aspect of the present disclosure. Similarly, the first feedback latency described according to the fifth aspect of the present disclosure may correspond to the first feedback latency described according to the first aspect of the present disclosure.
In accordance with an exemplary embodiment, the first feedback latency may be related to downlink channel processing time of the terminal device. In an embodiment, the downlink channel processing time may be determined based at least in part on the numerology of the S cell and a numerology of a Pcell of the terminal device.
In accordance with an exemplary embodiment, the information about the Scell may indicate that the Scell is configured for the terminal device by the network node.
In accordance with an exemplary embodiment, the configuration of the Scell for the terminal device may be performed according to one or more of:
In accordance with an exemplary embodiment, the Scell may be one of cells configured for the terminal device. In this case, the information about the Scell may indicate that the Scell is activated for the terminal device by the network node.
In accordance with an exemplary embodiment, the activation of the Scell for the terminal device may be performed according to one or more of:
In accordance with an exemplary embodiment, the Scell may be one of cells activated for the terminal device. In this case, the information about the Scell may indicate that the Scell is scheduled for the terminal device by the network node.
In accordance with an exemplary embodiment, the scheduling of the Scell for the terminal device may be performed according to one or more of:
In accordance with an exemplary embodiment, the terminal device may receive the information about the Scell in a RRC message, a MAC CE and/or DCI.
In accordance with an exemplary embodiment, the information about the Scell may also be related to one or more other Scells of the terminal device. In an embodiment, the one or more other Scells may be selected for the terminal device by the network node according to feedback latencies of the terminal device which may be based at least in part on numerologies of the one or more other Scells.
According to a sixth aspect of the present disclosure, there is provided an apparatus which may be implemented as a terminal device. The apparatus comprises one or more processors and one or more memories comprising computer program codes. The one or more memories and the computer program codes may be configured to, with the one or more processors, cause the apparatus at least to receive information about a Scell of the terminal device from a network node. The Scell may be selected for the terminal device by the network node according to first feedback latency of the terminal device with respect to the network node. The first feedback latency may be based at least in part on a numerology of the Scell. According to some exemplary embodiments, the one or more memories and the computer program codes may be configured to, with the one or more processors, cause the apparatus at least further to determine the Scell of the terminal device according to the received information.
In accordance with some exemplary embodiments, the one or more memories and the computer program codes may be configured to, with the one or more processors, cause the apparatus according to the sixth aspect of the present disclosure at least to perform any step of the method according to the fifth aspect of the present disclosure.
According to a seventh aspect of the present disclosure, there is provided a computer-readable medium having computer program codes embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to the fifth aspect of the present disclosure.
According to an eighth aspect of the present disclosure, there is provided an apparatus which may be implemented as a terminal device. The apparatus may comprise a receiving unit and a determining unit. In accordance with some exemplary embodiments, the receiving unit may be operable to carry out at least the receiving step of the method according to the fifth aspect of the present disclosure. The determining unit may be operable to carry out at least the determining step of the method according to the fifth aspect of the present disclosure.
According to a ninth aspect of the present disclosure, there is provided a method implemented in a communication system which may include a host computer, a base station and a UE. The method may comprise providing user data at the host computer. Optionally, the method may comprise, at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the base station which may perform any step of the method according to the first aspect of the present disclosure.
According to a tenth aspect of the present disclosure, there is provided a communication system including a host computer. The host computer may comprise processing circuitry configured to provide user data, and a communication interface configured to forward the user data to a cellular network for transmission to a UE. The cellular network may comprise a base station having a radio interface and processing circuitry. The base station's processing circuitry may be configured to perform any step of the method according to the first aspect of the present disclosure.
According to an eleventh aspect of the present disclosure, there is provided a method implemented in a communication system which may include a host computer, a base station and a UE. The method may comprise providing user data at the host computer. Optionally, the method may comprise, at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the base station. The UE may perform any step of the method according to the fifth aspect of the present disclosure.
According to a twelfth aspect of the present disclosure, there is provided a communication system including a host computer. The host computer may comprise processing circuitry configured to provide user data, and a communication interface configured to forward user data to a cellular network for transmission to a UE. The UE may comprise a radio interface and processing circuitry. The UE's processing circuitry may be configured to perform any step of the method according to the fifth aspect of the present disclosure.
According to a thirteenth aspect of the present disclosure, there is provided a method implemented in a communication system which may include a host computer, a base station and a UE. The method may comprise, at the host computer, receiving user data transmitted to the base station from the UE which may perform any step of the method according to the fifth aspect of the present disclosure.
According to a fourteenth aspect of the present disclosure, there is provided a communication system including a host computer. The host computer may comprise a communication interface configured to receive user data originating from a transmission from a UE to a base station. The UE may comprise a radio interface and processing circuitry. The UE's processing circuitry may be configured to perform any step of the method according to the fifth aspect of the present disclosure.
According to a fifteenth aspect of the present disclosure, there is provided a method implemented in a communication system which may include a host computer, a base station and a UE. The method may comprise, at the host computer, receiving, from the base station, user data originating from a transmission which the base station has received from the UE. The base station may perform any step of the method according to the first aspect of the present disclosure.
According to a sixteenth aspect of the present disclosure, there is provided a communication system which may include a host computer. The host computer may comprise a communication interface configured to receive user data originating from a transmission from a UE to a base station. The base station may comprise a radio interface and processing circuitry. The base station's processing circuitry may be configured to perform any step of the method according to the first aspect of the present disclosure.
The disclosure itself, the preferable mode of use and further objectives are best understood by reference to the following detailed description of the embodiments when read in conjunction with the accompanying drawings, in which:
The embodiments of the present disclosure are described in detail with reference to the accompanying drawings. It should be understood that these embodiments are discussed only for the purpose of enabling those skilled persons in the art to better understand and thus implement the present disclosure, rather than suggesting any limitations on the scope of the present disclosure. Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present disclosure should be or are in any single embodiment of the disclosure. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present disclosure. Furthermore, the described features, advantages, and characteristics of the disclosure may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the disclosure may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the disclosure.
As used herein, the term “communication network” refers to a network following any suitable communication standards, such as new radio (NR), long term evolution (LTE), LTE-Advanced, wideband code division multiple access (WCDMA), high-speed packet access (HSPA), and so on. Furthermore, the communications between a terminal device and a network node in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G), the second generation (2G), 2.5G, 2.75G, the third generation (3G), 4G, 4.5G, 5G communication protocols, and/or any other protocols either currently known or to be developed in the future.
The term “network node” refers to a network device in a communication network via which a terminal device accesses to the network and receives services therefrom. The network node may refer to a base station (BS), an access point (AP), a multi-cell/multicast coordination entity (MCE), a controller or any other suitable device in a wireless communication network. The BS may be, for example, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), a next generation NodeB (gNodeB or gNB), a remote radio unit (RRU), a radio header (RH), a remote radio head (RRH), a relay, a low power node such as a femto, a pico, and so forth.
Yet further examples of the network node comprise multi-standard radio (MSR) radio equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, positioning nodes and/or the like. More generally, however, the network node may represent any suitable device (or group of devices) capable, configured, arranged, and/or operable to enable and/or provide a terminal device access to a wireless communication network or to provide some service to a terminal device that has accessed to the wireless communication network.
The term “terminal device” refers to any end device that can access a communication network and receive services therefrom. By way of example and not limitation, the terminal device may refer to a mobile terminal, a user equipment (UE), or other suitable devices. The UE may be, for example, a subscriber station, a portable subscriber station, a mobile station (MS) or an access terminal (AT). The terminal device may include, but not limited to, portable computers, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, a mobile phone, a cellular phone, a smart phone, a tablet, a wearable device, a personal digital assistant (PDA), a vehicle, and the like.
As yet another specific example, in an Internet of things (IoT) scenario, a terminal device may also be called an IoT device and represent a machine or other device that performs monitoring, sensing and/or measurements etc., and transmits the results of such monitoring, sensing and/or measurements etc. to another terminal device and/or a network equipment. The terminal device may in this case be a machine-to-machine (M2M) device, which may in a 3rd generation partnership project (3GPP) context be referred to as a machine-type communication (MTC) device.
As one particular example, the terminal device may be a UE implementing the 3GPP narrow band Internet of things (NB-IoT) standard. Particular examples of such machines or devices are sensors, metering devices such as power meters, industrial machinery, or home or personal appliances, e.g. refrigerators, televisions, personal wearables such as watches etc. In other scenarios, a terminal device may represent a vehicle or other equipment, for example, a medical instrument that is capable of monitoring, sensing and/or reporting etc. on its operational status or other functions associated with its operation.
As used herein, the terms “first”, “second” and so forth refer to different elements. The singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises”, “comprising”, “has”, “having”, “includes” and/or “including” as used herein, specify the presence of stated features, elements, and/or components and the like, but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof. The term “based on” is to be read as “based at least in part on”. The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment”. The term “another embodiment” is to be read as “at least one other embodiment”. Other definitions, explicit and implicit, may be included below.
The concept of carrier aggregation (CA) is introduced by 3GPP in LTE Release 10. Carrier aggregation may refer to concatenation of multiple carriers. Application of carrier aggregation may increase bandwidth and consecutive data rate of the system. LTE Release 10 provides support for 5 component carriers (CCs). For example, LTE may support five bandwidth options, including 1.4 MHz, 3 MHz, 5 MHz, 10 MHz and 20 MHz. With the maximum bandwidth and 5 CCs, LTE may provide the maximum bandwidth of 100 MHz. LTE Release 13 (i.e. LTE Advanced-PRO) supports 32 CCs, and hence 640 MHz can be achieved. Compared to LTE, 5G/NR may support carrier aggregation with up to 16 CCs and up to 1 GHz. Carrier aggregation of LTE and 5G/NR carriers may also be possible, which is known as dual connectivity (DC).
One of the differences between 4G networks and 5G networks may be that in 5G/NR carrier aggregation, carriers can use different numerologies (e.g., SCS, slots, etc.). For example, 3GPP may support CA combinations like frequency range 1+frequency range 1 (FR1+FR1), frequency range 2+frequency range 2 (FR2+FR2), and even FR1 (below 6 GHz)+FR2 (above 6 GHz in mmW range). As an example, multiple transmission numerologies may be supported as given by Table 1, where Δf indicates SCS in KHz, and μ is the SCS index.
As listed in Table 1, the SCS value 15 KHz corresponds to μ=0, the SCS value 30 KHz corresponds to μ=1, and so on. According to an exemplary embodiment, only the SCS values 15 KHz, 30 KHz and 60 KHz for FR1, and the SCS values 120 KHz and 240 KHz for FR2 may be applicable.
Some exemplary band combinations for inter-band NR CA between FR1 and FR2 are shown in Table 2.
Normally, there may be several benefits brought by downlink/uplink (DL/UL) carrier aggregation. For example, adding an extra carrier for data transmission may achieve higher DL/UL throughput of a UE. In addition, a carrier with lower band may have better coverage than a carrier with higher band, so the carrier aggregation by combining carriers with lower band and higher band may enhance cell coverage and thus is popular in 5G/NR networks. Although support of different numerologies in carrier aggregation can improve network throughput and coverage, it may cause larger HARQ feedback delay in some scenarios.
In another exemplary embodiment, if the SCS value for transmission of a UE (e.g. using time division duplex (TDD)) is 120 KHz, then for HARQ feedback on PUCCH, the UE's PDSCH processing time is 24 OFDM symbols, and for HARQ feedback on PUSCH, the UE's PDSCH processing time is 25 OFDM symbols. Considering TDD pattern with DL-DL-DL-UL (DDDU) as shown in
Various exemplary embodiments of the present disclosure propose a solution to enable a network node (e.g., a gNB, etc.) to control carrier combination or carrier aggregation for a UE, e.g., according to traffic type, QoS requirement, etc. By implementing various embodiments, the gNB may select one or more transmission carriers or Scells for the UE according to the corresponding HARQ latency. In this way, the gNB can determine the optimal carrier combination with lower feedback latency for the UE, which may benefit the UE with low latency requirement in the carrier aggregation scenario.
In accordance with an exemplary embodiment, before Scell configuration in radio resource control (RRC), a gNB may determine which candidate Scell may be selected for a UE as a serving cell. Generally, the S cell may be selected according to its supported multiple-input multiple-output (MIMO) layers, traffic load and/or supported bandwidth. Alternatively or additionally, the gNB may configure several measurement events to get channel quality information for Scell selection. In an embodiment, the gNB may prioritize all candidate Scells and select the Scell that can bring higher improvement on throughput for the UE.
In accordance with an exemplary embodiment, a gNB may select one or more Scells to be configured/activated/scheduled for a UE, according to HARQ latency. When performing Scell selection, the gNB may calculate HARQ latency for each Scell, e.g. based at least in part on the numerology (and optionally frame pattern) of the Pcell and/or Scell for the UE. As an example, the HARQ latency may be derived from the UE's PDSCH processing time that may depend on the Pcell's numerology and the Scell's numerology. In addition, the frame pattern may also be considered, because the UE may only transmit DL HARQ feedback to the gNB in an UL slot.
In accordance with an exemplary embodiment, the UE's PDSCH processing time Tproc,1 may be calculated as below:
T
proc,1=((N1+d1,1)(2048+144)κ2−μ)Tc (1)
where
In accordance with an exemplary embodiment, the gNB may calculate the UE's PDSCH processing time for non-CA case and CA case respectively, e.g., according to formula (1). Assuming that the UE has processing capability 1 (which may be used to set N1) and d1,1=0, then the UE's PDSCH processing time nonCATproc,1 for non-CA case may be calculated by μ referring to (μPDCCH, μPDSCH, μUL) of the Pcell's numerology. For CA case, the UE's PDSCH processing time scellmCATproc,1 for Scell candidate in may be calculated by μ referring to (μPDCCH, μPDSCH, μUL) of the Pcell's numerology and the Scell's numerology, where μUL is based on the Pcell's numerology, and (μPDCCH, μPDSCH) is based on the Scell's numerology.
According to an embodiment for the non-CA case with 120 KHz carrier, ρ=3, N1=24, d1,1=0, κ=Ts/Tc=64 and Tc=1/(Δfmax·Nf), where Δfmax=480·103 Hz and Nf=4096, then the UE's PDSCH processing time nonCATproc,1 may be calculated as below:
nonCATproc,1=(24*(2048+144)*64*2{circumflex over ( )}(−3))/(480*103*4096)=214 μs (2)
According to an embodiment for the DL 2CC CA case with carrier combination (15 KHz carrier0+120 KHz carrier1), the UE's PDSCH processing time scellmCATproc,1 may be calculated as below:
T
proc,1_c0=(14*(2048+144)*64*2{circumflex over ( )}(0))/(480*103*4096)=999 μs (3)
T
proc,1_c1=(24*(2048+144)*64*2{circumflex over ( )}(−3))/(480*103*4096)=214 μs (4)
scellmCATproc,1=max(999,214) μs=999 μs (5)
According to the UE's PDSCH processing time, the gNB may calculate the minimum number of slots from downlink scheduling of the UE to uplink feedback to the downlink scheduling by the UE, i.e. the minimum K1 (also called minK1 for short), for both non-CA case and CA case.
In accordance with an exemplary embodiment, minK1 for the non-CA case, K1nonCA, may be calculated so that K1nonCA can fulfill formula (6), and minK1 for the CA case, K1CAscell_m, may be calculated so that K1CAscell_m can fulfill formula (7).
(K1nonCA−1)*Pcell symbol number in one slot*Pcell one symbol duration>=nonCATproc,1 (6)
(K1CAscell_m−1)*Pcell symbol number in one slot*Pcell one symbol duration>=scellmCATproc,1 (7)
According to an embodiment for 120 KHz, one slot is 0.125 ms with 14 symbols, and thus 214 μs may correspond to 25 symbols and 999 μs may correspond to 113 symbols. Then minK1 for the non-CA case K1nonCA and minK1 for the CA case K1CAscell_m may be calculated as below.
(K1nonCA−1)*14>=25→non-CA case: K1nonCA>=3 (8)
(K1CAscell_m−1)*14>=113→CA case: K1CAscell_m>=10 (9)
Table 3 shows the comparison between minK1 for non-CA case and CA case.
According to the comparison given in Table 3, it can be seen that when applying CA such as (120 KHz+15 KHz) DL CA, minK1 is enlarged from 3 to 10 for 120 KHz numerology carrier.
In accordance with an exemplary embodiment, the gNB may adjust minK1 according to associated frame pattern for both non-CA case and CA case. Since only UL slot may be used to send DL HARQ bit back to the gNB, minK1 may be adjusted according to TDD pattern, so as to make sure that minK1 is valid in TDD pattern.
In an embodiment, a minK1 adjustment procedure for non-CA case may be performed for each Pcell's UL slot in one frame pattern. According to the adjustment procedure, if the index which is smaller by K1nonCA than the index “ULslotN” of the Pcell's UL slot points to a DL slot, the minK1 for non-CA case K1nonCA may not be adjusted, and the adjustment procedure may end. If the index which is smaller by K1nonCA than the index “ULslotN” of the Pcell's UL slot points to an UL slot, then K1nonCA may be adjusted by increasing K1nonCA by 1. The adjustment procedure may be repeated with the adjusted K1nonCA in each loop, until it is determined that there is no need to adjust K1nonCA.
Similarly, in another embodiment, a minK1 adjustment procedure for CA case may be performed for each Pcell's UL slot in one frame pattern. According to the adjustment procedure, if the index which is smaller by K1CAscel_m than the index “ULslotN” of the Pcell's UL slot points to a DL slot, the minK1 for CA case K1CAscel_m may not be adjusted, and the adjustment procedure may end. If the index which is smaller by K1CAscel_m than the index “ULslotN” of the Pcell's UL slot points to an UL slot, then K1CAscel_m may be adjusted by increasing K1CAscel_m by 1. The adjustment procedure may be repeated with the adjusted K1CAscel_m in each loop, until it is determined that there is no need to adjust K1CAscel_m.
In accordance with an exemplary embodiment, the gNB may prioritize all available Scell candidates by minK1. For example, the gNB may calculate minK1 for all carrier combinations of Pcell and one or more Scell candidates, and sort the Scell candidates (or carrier combinations) by the corresponding values of minK1, e.g., in a Scell candidate list. Then the gNB may determine or select a Scell from the Scell candidate list, according to a specific criterion. In an embodiment, the gNB may select the Scell with the lowest minK1 value in the Scell list. In another embodiment, the gNB may select the Scell with a minK1 value lower than a threshold minK1_threshold from the Scell list. If the gNB can support more CCs, then several Scells may be selected from the Scell list.
In accordance with an exemplary embodiment, the gNB may determine whether to select one or more Scells according to a control parameter. For example, if the control parameter is set to enable the Scell selection, then the gNB may select a Scell with a lower minK1 value from the Scell list. If the control parameter is set to disable the Scell selection, then the gNB may not select a Scell from the Scell list.
In accordance with an exemplary embodiment, if the difference between minK1 for nonCA case and minK1 for CA case is larger than a specific value, the gNB may not configure CA at all. In this case, the gNB may not select a Scell from the Scell list. Alternatively or additionally, if the difference between minK1 for nonCA case and minK1 for CA case is less than another specific value, the gNB may select a Scell from the Scell list and configure CA correspondingly.
In accordance with an exemplary embodiment, the gNB may maintain a Scell list. After the UE sets up a connection with the gNB, the gNB may select one or more Scells from the Scell list according to the UE's traffic type. For example, if the UE requires low latency data (e.g., which may be indicated by QoS requirements, etc.) for a long time (e.g., about one or more seconds, etc.), then the gNB may select a Scell with a lower minK1 or no Scell for the UE.
In accordance with an exemplary embodiment, the selected Scell(s) may be configured for the UE by RRC signaling. As an example, the Scell may be configured, e.g. as described in 3GPP TS 38.331 V16.1.0 (where the entire content of this technical specification is incorporated into the present disclosure by reference), by RRC Reconfiguration as below:
In accordance with an exemplary embodiment, one or more Scells may be selected from a set of configured Scells in CA, e.g., according to the corresponding minK1 values. In this case, the selected Scell(s) may be activated or deactivated for the UE. As an example, the gNB may decide whether to activate or deactivate the configured Scell for the UE, e.g., as described in 3GPP TS 38.321 V16.1.0 (where the entire content of this technical specification is incorporated into the present disclosure by reference), by the Scell Activation/Deactivation MAC CE.
In accordance with an exemplary embodiment, if the Scell may bring larger minK1 for CA compared with the case of Pcell only, then a large-latency activation flag may be set or maintained to true. According to an embodiment, the gNB may not activate a Scell for the UE if the large-latency activation flag is true. According to another embodiment, the gNB may not activate a Scell or may deactivate a Scell, if the large-latency activation flag is true for a UE which may require low latency data during a period time (e.g., several transmission time intervals (TTIs), or tens to hundreds of milliseconds, etc.).
In accordance with an exemplary embodiment, one or more Scells may be selected from a set of activated Scells in CA, e.g., according to the corresponding minK1 values. In this case, the selected Scell(s) may be scheduled for the UE. As an example, the gNB may decide how to schedule the Pcell and the Scell, and send scheduling information to the UE by DCI.
In accordance with an exemplary embodiment, if the Scell may bring larger minK1 for CA compared with the case of Pcell only, then a large-latency scheduling flag may be set or maintained to true. According to an embodiment, the gNB may not schedule a Scell for the UE if the large-latency scheduling flag is true. According to another embodiment, the gNB may not schedule a Scell, if the large-latency scheduling flag is true for a UE which may require low latency data for this scheduling TTI.
It can be appreciated that the parameter names (e.g., nonCATproc,1, scellmCATproc,1, K1nonCA, K1CAscell_m, minK1, etc.) and the threshold (e.g., minK1_threshold) used herein are exemplary, and other parameter names and thresholds may also be used to indicate the same or similar information. In addition, it can be appreciated that algorithms, functions and variables related to the determination of HARQ latency as described in connection with formulas (1)˜(9) and
It is noted that some embodiments of the present disclosure are mainly described in relation to 5G or NR specifications being used as non-limiting examples for certain exemplary network configurations and system deployments. As such, the description of exemplary embodiments given herein specifically refers to terminology which is directly related thereto. Such terminology is only used in the context of the presented non-limiting examples and embodiments, and does naturally not limit the present disclosure in any way. Rather, any other system configuration or radio technologies may equally be utilized as long as exemplary embodiments described herein are applicable.
According to the exemplary method 400 illustrated in
In accordance with an exemplary embodiment, the first feedback latency may correspond to a carrier combination of the candidate cell and a Pcell of the terminal device. For example, the first feedback latency may be indicated by one or more parameters such as scellmCATproc,1, K1CAscell_m, etc.
In accordance with an exemplary embodiment, the first feedback latency may be further based at least in part on one or more of: a numerology of a Pcell of the terminal device; a frame pattern (e.g., TDD/FDD pattern) for the terminal device; and a capability of the terminal device.
In accordance with an exemplary embodiment, the calculation of the first feedback latency may comprise estimating downlink channel processing time of the terminal device, according to the numerology of the candidate cell and a numerology of a Pcell of the terminal device. Then the first feedback latency may be calculated according to the downlink channel processing time of the terminal device. In an embodiment, the first feedback latency may be adjusted according to a frame pattern for the terminal device, e.g., as described with respect to
In accordance with an exemplary embodiment, the first feedback latency may be equal to a minimum number of slots from downlink scheduling of the terminal device by the network node to uplink feedback to the downlink scheduling by the terminal device, e.g. minK1 as described with respect to Table 3 and
In accordance with an exemplary embodiment, the candidate cell may be included in a cell list for the terminal device according to the first feedback latency. For example, various candidate cells in the cell list may be sorted in ascending or descending order of the corresponding feedback latency values.
In accordance with an exemplary embodiment, the network node may determine to select the candidate cell as the Scell of the terminal device, in response to the first feedback latency meeting one or more of the following criterions:
In accordance with an exemplary embodiment, selecting the candidate cell as the Scell of the terminal device may comprise configuring the candidate cell as the Scell of the terminal device. In an embodiment, the candidate cell may be configured as the Scell of the terminal device according to one or more of:
In accordance with an exemplary embodiment, the candidate cell may be one of cells configured for the terminal device. In this case, selecting the candidate cell as the Scell of the terminal device may comprise activating the candidate cell as the Scell of the terminal device. In an embodiment, the candidate cell may be activated as the Scell of the terminal device according to one or more of:
In accordance with an exemplary embodiment, the candidate cell may be one of cells activated for the terminal device. In this case, selecting the candidate cell as the Scell of the terminal device may comprise scheduling the candidate cell as the Scell of the terminal device. In an embodiment, the candidate cell may be scheduled as the Scell of the terminal device according to one or more of:
In accordance with an exemplary embodiment, the network node may transmit information about the Scell to the terminal device. For example, the information about the Scell may include Scell configuration information, Scell activation information and/or Scell scheduling information, etc. According to an embodiment, the information about the Scell may be transmitted to the terminal device in a RRC message, a MAC CE and/or DCI.
In accordance with an exemplary embodiment, the network node may select one or more other candidate cells as Scells of the terminal device, according to feedback latencies of the terminal device which may be calculated based at least in part on numerologies of the one or more other candidate cells. Correspondingly, the network node may transmit information about the selected Scells to the terminal device.
According to the exemplary method 500 illustrated in
It can be appreciated that the steps, operations and related configurations of the method 500 illustrated in
In accordance with an exemplary embodiment, the first feedback latency may be related to downlink channel processing time of the terminal device. As described with respect to
In accordance with an exemplary embodiment, the information about the Scell may indicate that the Scell is configured for the terminal device by the network node. In an embodiment, the configuration of the Scell for the terminal device may be according to a first parameter to enable/disable Scell configuration for the terminal device, a traffic type of the terminal device, and/or a QoS requirement of the terminal device during a first period of time.
In accordance with an exemplary embodiment, the Scell may be one of cells configured for the terminal device. In this case, the information about the Scell may indicate that the Scell is activated for the terminal device by the network node. In an embodiment, the activation of the Scell for the terminal device may be according to a second parameter to enable/disable Scell activation for the terminal device, a traffic type of the terminal device, and/or a QoS requirement of the terminal device during a second period of time.
In accordance with an exemplary embodiment, the Scell may be one of cells activated for the terminal device. In this case, the information about the Scell may indicate that the Scell is scheduled for the terminal device by the network node. In an embodiment, the scheduling of the Scell for the terminal device may be according to a third parameter to enable/disable Scell scheduling for the terminal device, a traffic type of the terminal device, and/or a QoS requirement of the terminal device during a third period of time.
In accordance with an exemplary embodiment, the information about the Scell may be received by the terminal device in one or more of: a RRC message, a MAC CE, and DCI. According to an exemplary embodiment, the information about the Scell may also be related to one or more other Scells of the terminal device. The one or more other Scells may be selected for the terminal device by the network node according to feedback latencies of the terminal device which may be based at least in part on numerologies of the one or more other Scells.
Various exemplary embodiments according to the present disclosure may enable carrier combination or carrier aggregation to be controlled adaptively. In accordance with some exemplary embodiments, a gNB may select one or more Scells for a UE, e.g., according to feedback latency of the UE. For example, the gNB may calculate HARQ latency (e.g., minK1, etc.) for each Scell according to the numerology and potentially frame pattern (e.g. FDD/TDD pattern) of both Pcell and Scell. Then the gNB may prioritize all available Scell candidates by minK1 in a Scell candidate list, and determine which Scell(s) to select from the Scell candidate list. The Scell selection according to various embodiments may be applied to implement Scell configuration, Scell activation and/or Scell scheduling for the UE. In an embodiment, the selected Scell(s) from the Scell candidates may be configured for the UE. Alternatively or additionally, one or more Scells selected from the configured cells may be activated for the UE. It can be appreciated that the configured Scell may also be determined based on other suitable schemes in addition or alternative to the HARQ latency. Alternatively or additionally, one or more Scells selected from the activated cells may be scheduled for the UE. It also can be appreciated that the activated Scell may also be determined based on other suitable schemes in addition or alternative to the HARQ latency. In an embodiment, a Scell which may cause higher HARQ delay may not be configured for a UE which may only have low latency traffic. In another embodiment, a Scell which may cause higher HARQ delay may not be activated for a UE which may have low latency traffic occasionally. In a further embodiment, a Scell which may cause higher HARQ delay may not be scheduled for a UE which may once have low latency traffic. Application of various exemplary embodiments can advantageously improve network performance and resource efficiency, and enhance flexibility of carrier combination configuration and CA implementation.
The various blocks shown in
In some implementations, the one or more memories 612 and the computer program codes 613 may be configured to, with the one or more processors 611, cause the apparatus 610 at least to perform any operation of the method as described in connection with
With reference to
The telecommunication network 710 is itself connected to a host computer 730, which may be embodied in the hardware and/or software of a standalone server, a cloud-implemented server, a distributed server or as processing resources in a server farm. The host computer 730 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. Connections 721 and 722 between the telecommunication network 710 and the host computer 730 may extend directly from the core network 714 to the host computer 730 or may go via an optional intermediate network 720. An intermediate network 720 may be one of, or a combination of more than one of, a public, private or hosted network; the intermediate network 720, if any, may be a backbone network or the Internet; in particular, the intermediate network 720 may comprise two or more sub-networks (not shown).
The communication system of
Example implementations, in accordance with an embodiment, of the UE, base station and host computer discussed in the preceding paragraphs will now be described with reference to
The communication system 800 further includes a base station 820 provided in a telecommunication system and comprising hardware 825 enabling it to communicate with the host computer 810 and with the UE 830. The hardware 825 may include a communication interface 826 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 800, as well as a radio interface 827 for setting up and maintaining at least a wireless connection 870 with the UE 830 located in a coverage area (not shown in
The communication system 800 further includes the UE 830 already referred to. Its hardware 835 may include a radio interface 837 configured to set up and maintain a wireless connection 870 with a base station serving a coverage area in which the UE 830 is currently located. The hardware 835 of the UE 830 further includes a processing circuitry 838, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The UE 830 further comprises software 831, which is stored in or accessible by the UE 830 and executable by the processing circuitry 838. The software 831 includes a client application 832. The client application 832 may be operable to provide a service to a human or non-human user via the UE 830, with the support of the host computer 810. In the host computer 810, an executing host application 812 may communicate with the executing client application 832 via the OTT connection 850 terminating at the UE 830 and the host computer 810. In providing the service to the user, the client application 832 may receive request data from the host application 812 and provide user data in response to the request data. The OTT connection 850 may transfer both the request data and the user data. The client application 832 may interact with the user to generate the user data that it provides.
It is noted that the host computer 810, the base station 820 and the UE 830 illustrated in
In
Wireless connection 870 between the UE 830 and the base station 820 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE 830 using the OTT connection 850, in which the wireless connection 870 forms the last segment. More precisely, the teachings of these embodiments may improve the latency and the power consumption, and thereby provide benefits such as lower complexity, reduced time required to access a cell, better responsiveness, extended battery lifetime, etc.
A measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 850 between the host computer 810 and the UE 830, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 850 may be implemented in software 811 and hardware 815 of the host computer 810 or in software 831 and hardware 835 of the UE 830, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 850 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which the software 811, 831 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 850 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the base station 820, and it may be unknown or imperceptible to the base station 820. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating the host computer 810's measurements of throughput, propagation times, latency and the like. The measurements may be implemented in that the software 811 and 831 causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 850 while it monitors propagation times, errors etc.
According to some exemplary embodiments, there is provided a method implemented in a communication system which may include a host computer, a base station and a UE. The method may comprise providing user data at the host computer. Optionally, the method may comprise, at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the base station which may perform any step of the exemplary method 400 as describe with respect to
According to some exemplary embodiments, there is provided a communication system including a host computer. The host computer may comprise processing circuitry configured to provide user data, and a communication interface configured to forward the user data to a cellular network for transmission to a UE. The cellular network may comprise a base station having a radio interface and processing circuitry. The base station's processing circuitry may be configured to perform any step of the exemplary method 400 as describe with respect to
According to some exemplary embodiments, there is provided a method implemented in a communication system which may include a host computer, a base station and a UE. The method may comprise providing user data at the host computer. Optionally, the method may comprise, at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the base station. The UE may perform any step of the exemplary method 500 as describe with respect to
According to some exemplary embodiments, there is provided a communication system including a host computer. The host computer may comprise processing circuitry configured to provide user data, and a communication interface configured to forward user data to a cellular network for transmission to a UE. The UE may comprise a radio interface and processing circuitry. The UE's processing circuitry may be configured to perform any step of the exemplary method 500 as describe with respect to
According to some exemplary embodiments, there is provided a method implemented in a communication system which may include a host computer, a base station and a UE. The method may comprise, at the host computer, receiving user data transmitted to the base station from the UE which may perform any step of the exemplary method 500 as describe with respect to
According to some exemplary embodiments, there is provided a communication system including a host computer. The host computer may comprise a communication interface configured to receive user data originating from a transmission from a UE to a base station. The UE may comprise a radio interface and processing circuitry. The UE's processing circuitry may be configured to perform any step of the exemplary method 500 as describe with respect to
According to some exemplary embodiments, there is provided a method implemented in a communication system which may include a host computer, a base station and a UE. The method may comprise, at the host computer, receiving, from the base station, user data originating from a transmission which the base station has received from the UE. The base station may perform any step of the exemplary method 400 as describe with respect to
According to some exemplary embodiments, there is provided a communication system which may include a host computer. The host computer may comprise a communication interface configured to receive user data originating from a transmission from a UE to a base station. The base station may comprise a radio interface and processing circuitry. The base station's processing circuitry may be configured to perform any step of the exemplary method 400 as describe with respect to
In general, the various exemplary embodiments may be implemented in hardware or special purpose chips, circuits, software, logic or any combination thereof. For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the disclosure is not limited thereto. While various aspects of the exemplary embodiments of this disclosure may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.
As such, it should be appreciated that at least some aspects of the exemplary embodiments of the disclosure may be practiced in various components such as integrated circuit chips and modules. It should thus be appreciated that the exemplary embodiments of this disclosure may be realized in an apparatus that is embodied as an integrated circuit, where the integrated circuit may comprise circuitry (as well as possibly firmware) for embodying at least one or more of a data processor, a digital signal processor, baseband circuitry and radio frequency circuitry that are configurable so as to operate in accordance with the exemplary embodiments of this disclosure.
It should be appreciated that at least some aspects of the exemplary embodiments of the disclosure may be embodied in computer-executable instructions, such as in one or more program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types when executed by a processor in a computer or other device. The computer executable instructions may be stored on a computer readable medium such as a hard disk, optical disk, removable storage media, solid state memory, random access memory (RAM), etc. As will be appreciated by one of skill in the art, the function of the program modules may be combined or distributed as desired in various embodiments. In addition, the function may be embodied in whole or partly in firmware or hardware equivalents such as integrated circuits, field programmable gate arrays (FPGA), and the like.
The present disclosure includes any novel feature or combination of features disclosed herein either explicitly or any generalization thereof. Various modifications and adaptations to the foregoing exemplary embodiments of this disclosure may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings. However, any and all modifications will still fall within the scope of the non-limiting and exemplary embodiments of this disclosure.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2020/107086 | 8/5/2020 | WO |
