The present disclosure relates, in general, to wireless communications and, more particularly, to channel raster and numbering.
All mobile communication systems have a carrier raster that defines a set of frequencies where radio frequency (RF) carriers can be placed for downlink (DL) and uplink (UL) communication. The set of frequencies has to be limited to some extent since RF carriers have to be contained within the frequency bands where the system is allowed to operate (also referred to as operating bands). There are also a limited number of carriers in each band, in order to facilitate an efficient cell search by wireless devices (e.g., user equipment (UE)).
When a wireless device is to first connect to a network, it does not have knowledge of the frequencies of the DL RF carrier(s) (also called RF channels) transmitted by the network. It performs a cell search by scanning the possible RF carrier positions and tries to identify and synchronize to available DL carriers. Once connected to a network, cell search also has to be performed continuously by the wireless device in order to provide mobility, since it needs to find and identify adjacent candidate cells for handover.
With more possible carrier positions, the time required for cell search increases. For this reason, there has to be a limited number of carrier positions in the carrier raster for a wireless device to perform cell search on.
5G systems, such as the New Radio (NR) Access being developed by 3GPP, will be able to operate in the same frequency bands as LTE, but also in new frequency bands in the millimetre (mm)-wave frequency range. These new bands are considerably larger than existing bands for LTE at lower frequencies and can be up to several gigahertz (GHz) wide. Using an RF carrier grid with, for example, 100 kHz separation could therefore lead to unmanageable cell search times, since there are so many possible raster points.
NR will be designed to operate with many possible RF channel bandwidths, and also with different possible numerologies (in terms of Orthogonal Frequency Division Multiplexed (OFDM) subcarrier spacing and other parameters). This could further increase the cell search time. It has therefore been proposed in 3GPP (see, for example, 3GPP TSG-RAN WG4 RAN4#1-NR, R4-1700187, “Synchronization signal frequency raster considerations,” Spokane, U.S.A, Jan. 17th-19th, 2016) to define a fixed set of synchronization channel frequencies (e.g., synchronization channel 205) on a synchronization channel raster (e.g., synchronization raster 200), as shown in
Synchronization channel 205 is part of RF channel 210, and thus consists of a number of OFDM subcarriers 220. This means that the grid positions of synchronization channel 205 would be aligned with the subcarriers of the complete RF carrier 210, which gives some restrictions on the possible positions of the complete RF carrier.
The proposed approach, however, suffers from certain deficiencies. For example, when the wireless device has identified a valid synchronization channel (e.g., synchronization channel 205), the wireless device will still not have full knowledge of the position and channel bandwidth of the complete RF carrier 210. The synchronization channel can be in any possible position within RF carrier 210, which can have any of the different RF channel bandwidths allowed in the operating band.
There is also a secondary problem with the proposed scheme, in that the OFDM subcarrier grid is aligned between synchronization channel 205 and the complete RF carrier 210. This will give a granularity in how to position RF carrier 210, which cannot be smaller than the subcarrier spacing. This can cause problems due to regulations imposed through license conditions for an operator of a network (e.g., an NR network). For example, if the license specifies a very strict frequency range (i.e., “licence block”) in which the operator can place an RF carrier, it may not be possible to place RF carrier 210 exactly centered in that license block due to the coarse granularity imposed by the subcarrier spacing of NR. This creates a risk that RF emissions “spill” over on one side of the license block, potentially violating the license conditions or other regulation(s) imposed on the operation.
To address the foregoing problems with existing solutions, disclosed is a method in a wireless device. The method comprises identifying a synchronization channel part of an RF carrier in an operating band. The method comprises obtaining system information for use in determining a position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier. The method comprises determining, based on the obtained system information, the position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier.
In certain embodiments, identifying the synchronization channel part of the RF carrier in the operating band may comprise: determining a plurality of pre-determined synchronization raster points based on a synchronization channel raster associated with the synchronization channel part of the RF carrier, each of the pre-determined synchronization raster points defining a possible location of the synchronization channel part of the RF carrier; and performing a cell search on one or more of the plurality of pre-determined synchronization raster points to identify the synchronization channel part of the RF carrier.
In certain embodiments, obtaining system information may comprise receiving a system information message.
In certain embodiments, the synchronization channel part of the RF carrier may comprise a synchronization signal block comprising a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) transmitted together with a Physical Broadcast Channel (PBCH). In certain embodiments, at least a portion of the system information may be contained in the PBCH.
In certain embodiments, the obtained system information may comprise one or more offset values. In certain embodiments, the one or more offset values may comprise at least a first offset value defining an offset from the synchronization channel part of the RF carrier to a center frequency of the RF carrier. In certain embodiments, the center frequency of the RF carrier may correspond to a carrier raster point of a carrier raster associated with the RF carrier.
In certain embodiments, the method may comprise determining, based on the obtained system information, one or more of: a bandwidth of the RF carrier; and a subcarrier spacing of one or more data channels.
In certain embodiments, the method may comprise establishing a connection with a network node via the RF carrier.
In certain embodiments, the method may comprise receiving an instruction to perform a handover to another RF carrier at another frequency.
In certain embodiments, the position of the RF carrier in the operating band may not be centered within a license block, and the method may comprise receiving a truncated transmission of an OFDM symbol, the truncated transmission may comprise one or more blanked subcarriers on at least one side of the transmission. In certain embodiments, the position of the RF carrier in the operating band may not be centered within a license block, and the method may comprise transmitting a truncated transmission of an OFDM symbol, the truncated transmission may comprise one or more blanked subcarriers on at least one side of the transmission.
Also disclosed is a wireless device. The wireless device comprises a receiver, a transmitter, and processing circuitry coupled to the receiver and the transmitter. The processing circuitry is configured to identify a synchronization channel part of an RF carrier in an operating band. The processing circuitry is configured to obtain system information for use in determining a position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier. The processing circuitry is configured to determine, based on the obtained system information, the position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier.
Also disclosed is a wireless device. The wireless device comprises a receiving module, a communication module, and a determining module coupled to the receiving module and the communication module. The determining module is configured to identify a synchronization channel part of an RF carrier in an operating band. The determining module is configured to obtain system information for use in determining a position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier. The determining module is configured to determine, based on the obtained system information, the position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier.
Also disclosed is a computer program, the computer program comprising instructions configured to perform the above-described method in a wireless device. Also disclosed is a computer program product, the computer program product comprising a non-transitory computer-readable storage medium, the non-transitory computer-readable storage medium comprising a computer program comprising computer-executable instructions which, when executed on a processor, are configured to perform the above-described method in a wireless device.
Also disclosed is a method in a network node. The method comprises determining system information for use by a wireless device to determine a position of an RF carrier in an operating band relative to a synchronization channel part of the RF carrier. The method comprises sending the determined system information to the wireless device.
In certain embodiments, the synchronization channel part of the RF carrier may comprise a synchronization signal block comprising a primary synchronization signal and a secondary synchronization signal transmitted together with a PBCH. In certain embodiments, sending the determined system information to the wireless device may comprise sending at least a portion of the determined system information to the wireless device in the PBCH.
In certain embodiments, the determined system information may comprise one or more offset values. In certain embodiments, the one or more offset values may comprise at least a first offset value defining an offset from the synchronization channel part of the RF carrier to a center frequency of the RF carrier. In certain embodiments, the center frequency of the RF carrier may correspond to a carrier raster point of a carrier raster associated with the RF carrier.
In certain embodiments, the determined system information may comprise one or more of: a bandwidth of the RF carrier; and a subcarrier spacing of one or more data channels.
In certain embodiments, the method may comprise establishing a connection with the wireless device via the RF carrier. In certain embodiments, the method may comprise sending an instruction to the wireless device to perform a handover to another RF carrier at another frequency.
In certain embodiments, the position of the RF carrier in the operating band may not be centered within a license block, and the method may comprise receiving a truncated transmission of an OFDM symbol, the truncated transmission may comprise one or more blanked subcarriers on at least one side of the transmission.
In certain embodiments, the position of the RF carrier in the operating band may not be centered within a license block, and the method may comprise transmitting a truncated transmission of an OFDM symbol, the truncated transmission may comprise one or more blanked subcarriers on at least one side of the transmission.
Also disclosed is a network node. The network node comprises a receiver, a transmitter, and processing circuitry coupled to the receiver and the transmitter. The processing circuitry is configured to determine system information for use by a wireless device to determine a position of an RF carrier in an operating band relative to a synchronization channel part of the RF carrier. The processing circuitry is configured to send, via the transmitter, the determined system information to the wireless device.
Also disclosed is a network node. The network node comprises a receiving module, a communication module, and a determining module. The determining module is configured to determine system information for use by a wireless device to determine a position of an RF carrier in an operating band relative to a synchronization channel part of the RF carrier. The communication module is configured to send, via the transmitter, the determined system information to the wireless device.
Also disclosed is a computer program, the computer program comprising instructions configured to perform the above-described method in a network node. Also disclosed is a computer program product, the computer program product comprising a non-transitory computer-readable storage medium, the non-transitory computer-readable storage medium comprising a computer program comprising computer-executable instructions which, when executed on a processor, are configured to perform the above-described method in a network node.
Certain embodiments of the present disclosure may provide one or more technical advantages. For example, certain embodiments may provide the position of the RF channel as a relative offset from the synchronization channel, which may advantageously provide fewer possible RF channel positions and thereby save information (e.g., bits) in the system information message. As another example, certain embodiments may provide information about blanked OFDM subcarriers on one side of the RF carrier, which may advantageously allow emissions to be kept within regulatory requirements (for example, in cases where the frequency range available to the operator is very strict). As another example, certain embodiments may advantageously prevent unnecessary reduction in spectrum utilization, for example by providing information about blanked subcarriers in the system information only when it is necessary. Other advantages may be readily apparent to one having skill in the art. Certain embodiments may have none, some, or all of the recited advantages.
For a more complete understanding of the disclosed embodiments and their features and advantages, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:
As described above, 5G systems, such as NR, will be able to operate in the same frequency bands as LTE, but also in new frequency bands in the mm-wave frequency range. These new bands are considerably larger than existing bands for LTE at lower frequencies and can be up to several gigahertz (GHz) wide. Using an RF carrier grid with, for example, 100 kHz separation could therefore lead to unmanageable search times, since there are so many possible raster points. It has been proposed to define a fixed set of synchronization channel frequencies on a synchronization channel raster, as described above in relation to
When the wireless device has identified the position of the synchronization channel, it needs to further identify the full RF channel. In certain embodiments, a network node (e.g., a base station (BS)) provides a system information message to the wireless device that is located within the span of the synchronization channel. The system information identifies the position of the RF channel center relative to the synchronization channel. This system information also provides the RF channel bandwidth, subcarrier spacing used for the data channels, and other information needed by the wireless device to fully acquire and/or continue to set up a connection with the network node.
As noted above, if the RF channel is not centered within the license block of the operator, this can cause the problem that RF emissions “spill over” on one side. In certain embodiments, the transmission of the OFDM signal can be “truncated” by not transmitting (e.g., blanking) one or more subcarriers on the side of the transmission that potentially causes the problem. In some cases, how many subcarriers to blank (if any), and on what side of the transmission, may be provided to the wireless device through the system information message.
According to one example embodiment, a method in a wireless device is disclosed. The wireless device identifies a synchronization channel part of an RF carrier in an operating band. In some cases, the wireless device identifies the synchronization channel part of the RF carrier in the operating band by determining a plurality of pre-determined synchronization raster points based on a synchronization channel raster associated with the synchronization channel part of the RF carrier. Each of the pre-determined synchronization raster points defines a possible location of the synchronization channel part of the RF carrier. The wireless device performs a cell search on one or more of the plurality of pre-determined synchronization raster points to identify the synchronization channel part of the RF carrier. The wireless device obtains system information (e.g., by receiving a system information message) for use in determining a position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier. In some cases, the obtained system information may include one or more offset values (e.g., a first offset value defining an offset from the synchronization channel part of the RF carrier to a center frequency of the RF carrier). The wireless device determines, based on the obtained system information, the position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier. In some cases, the wireless device establishes a connection with the network node via the RF carrier. In some cases, the position of the RF carrier in the operating band may not be centered within a license block, and the wireless device may receive and/or transmit a truncated transmission of an OFDM symbol.
According to another example embodiment, a method in a network node is disclosed. The network node determines system information for use by a wireless device to determine a position of an RF carrier in an operating band relative to a synchronization channel part of the RF carrier. The determined system information may, for example, include one or more offset values (e.g., a first offset value defining an offset from the synchronization channel part of the RF carrier to a center frequency of the RF carrier). In some cases, the determined system information may also include a bandwidth of the RF carrier, a subcarrier spacing of one or more data channels, and/or a number of subcarriers to blank (and, in some cases, on which side of the transmission they are located). The network node sends the determined system information to the wireless device. In some cases, the network node may establish a connection with the wireless device via the RF carrier. In some cases, the position of the RF carrier in the operating band may not be centered within a license block, and the network node may receive and/or transmit a truncated transmission of an OFDM symbol.
Certain embodiments of the present disclosure may provide one or more technical advantages. As one example, certain embodiments may provide the position of the RF channel as a relative offset from the synchronization channel, which may advantageously provide fewer possible RF channel positions and thereby save information (e.g., bits) in the system information message. As an example, if the operating band is 1200 megahertz (MHz) wide, and the RF channel can be anywhere on a 120 kHz raster, there are 10,000 possible raster positions. If the synchronization channel is on a synchronization channel raster with 24 MHz between raster point, the wireless device would know that the RF channel center is within a 24 MHz range, once it has identified the synchronization channel. There would now only be 200 possible RF channel positions, relative to the synchronization channel. By using a relative offset, the number of possible RF channel positions is therefore reduced from 10,000 to 200, which advantageously reduces the amount of information that needs to be broadcasted in the system information.
As another example, certain embodiments may provide information about blanked OFDM subcarriers on one side of the RF carrier, which may advantageously allow emissions to be kept within regulatory requirements (for example, in cases where the frequency range available to the operator is very strict). An alternative and less advantageous approach would be to design the RF carrier to always have extra margin at both sides of the transmission by always transmitting fewer subcarriers. This, however, would give a loss in terms of lower utilization of the spectrum (a waste of spectrum resources), especially in cases where there are no regulatory restrictions imposed on the sides of the transmission. In certain embodiments, by providing information about blanked subcarriers in the system information, the spectrum utilization is only reduced in cases where it is necessary.
Other advantages may be readily apparent to one having skill in the art. Certain embodiments may have none, some, or all of the recited advantages.
In certain embodiments, network nodes 315 may interface with a radio network controller (RAC). The RNC may control network nodes 315 and may provide certain radio resource management functions, mobility management functions, and/or other suitable functions. In certain embodiments, the functions of the RNC may be included in network node 315. The RNC may interface with a core network node. In certain embodiments, the RNC may interface with the core network node via an interconnecting network 320. Interconnecting network 320 may refer to any interconnecting system capable of transmitting audio, video, signals, data, messages, or any combination of the preceding. Interconnecting network 320 may include all or a portion of a public switched telephone network (PSTN), a public or private data network, a local area network (LAN), a metropolitan area network (MAN), a wide area network (WAN), a local, regional, or global communication or computer network such as the Internet, a wireline or wireless network, an enterprise intranet, or any other suitable communication link, including combinations thereof.
In some embodiments, the core network node may manage the establishment of communication sessions and various other functionalities for wireless devices 310. Wireless devices 310 may exchange certain signals with the core network node using the non-access stratum layer. In non-access stratum signaling, signals between wireless devices 310 and the core network node may be transparently passed through the radio access network (RAN). In certain embodiments, network nodes 315 may interface with one or more network nodes over an internode interface, such as, for example, an X2 interface.
As described above, example embodiments of network 300 may include one or more wireless devices 310, and one or more different types of network nodes capable of communicating (directly or indirectly) with wireless devices 310.
In some embodiments, the non-limiting term wireless device is used. Wireless devices 310 described herein can be any type of wireless device capable of communicating with network nodes 315 or another wireless device in a cellular or mobile communication system (e.g., over radio signals). Examples of wireless devices include a UE, a radio communication device, target device, UE, D2D UE, machine-type-communication (MTC) UE or UE capable of machine-to-machine (M2M) communication, low-cost and/or low-complexity UE, a sensor equipped with UE, tablet, Personal Digital Assistant (PDA), mobile terminals, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), USB dongles, Customer Premises Equipment (CPE), etc. Wireless devices 310 may operate under either normal coverage or enhanced coverage with respect to its serving cell. The enhanced coverage may be interchangeably referred to as extended coverage. Wireless devices 310 may also operate in a plurality of coverage levels (e.g., normal coverage, enhanced coverage level 1, enhanced coverage level 2, enhanced coverage level 3 and so on). In some cases, wireless devices 310 may also operate in out-of-coverage scenarios.
Also, in some embodiments the non-limiting term network node is used. It can be any kind of network node or radio network node. Examples of network nodes 315 include a BS, radio BS, Node B, multi-standard radio (MSR) radio node such as MSR BS, eNB, Master eNB (MeNB), Secondary eNB (SeNB), gNB, network controller, RNC, BS controller (BSC), relay node, donor node controlling relay, base transceiver station (BTS), access point (AP), radio AP, transmission point, transmission node, Remote Radio Unit (RRU), Remote Radio Head (RRH), nodes in distributed antenna system (DAS), Multi-cell/multicast Coordination Entity (MCE), core network node (e.g., Mobile Switching Center (MSC), Mobility Management Entity (MME), etc.), Operations & Management (O&M), Operations Support System (OSS), Self-Organizing Network (SON), positioning node (e.g., Evolved-Serving Mobile Location Center (E-SMLC)), Minimization of Drive Test (MDT), or any other suitable network node.
The terminology such as network node and wireless device should be considered non-limiting and does not imply a certain hierarchical relation between the two; in general “network node” could be considered as device 1 and “wireless device” as device 2, and these two devices communicate with each other over some radio channel.
Example embodiments of wireless devices 310, network nodes 315, and other network nodes (such as RNC or core network node) are described in more detail below with respect to
Although
As described above, when a wireless device (e.g., wireless device 310A) is to first connect to network 300, wireless device 310A does not have knowledge of the frequencies of the DL RF carrier(s) (which may be interchangeably referred to herein as RF channel (s)) transmitted by the network (e.g., by network node 315A). In certain embodiments, wireless device 310A determines the position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier. As described in more detail below, the RF carrier frequency is defined in two steps. First, through a synchronization channel raster and, in a second step, the final RF carrier frequency is defined on an RF channel raster relative to the synchronization channel. The synchronization channel numbering and raster is described in more detail below.
In some cases, the center frequency for the synchronization signal (SS) (e.g., SS block) may be different from the center frequency of the RF carrier. This opens up the possibility to have a synchronization signal raster that is more sparse than the channel raster that defines the possible RF carrier frequency (if some conditions are put on the placement and bandwidth of the synchronization channel). In certain embodiments, these conditions may include: a minimum RF channel bandwidth is defined for each operating band; the synchronization signal frequency raster is an integer multiple of data subcarrier spacing; and, in some cases, the bandwidth of the synchronization channel may be smaller than half of the RF channel bandwidth. As a result, there will be one complete synchronization channel contained inside the RF channel, regardless of where the RF channel is placed. An example is illustrated in
In certain embodiments, wireless device 310A identifies a synchronization channel part of an RF carrier in an operating band. In certain embodiments, the synchronization channel part of the RF carrier may comprise a synchronization signal block comprising a Primary Synchronization Signal (SSS) and a Secondary Synchronization Signal transmitted together with a Physical Broadcast Channel (PBCH).
Wireless device 310A may identify the synchronization channel part of the RF carrier in any suitable manner. As one example, wireless device 310A may determine a plurality of pre-determined synchronization raster points based on a synchronization channel raster associated with the synchronization channel part of the RF carrier. Each of the pre-determined synchronization raster points defines a possible location of the synchronization channel part of the RF carrier. Wireless device 310A may perform a cell search on one or more of the plurality of pre-determined synchronization raster points to identify the synchronization channel part of the RF carrier.
When wireless device 310A has identified the position of the synchronization channel, it needs to further identify the full RF channel. In certain embodiments, a network node (e.g., network node 315A) may determine system information for use by wireless device 310A to determine a position of the RF carrier in the operating band relative to the synchronization channel part of the RF carrier, and send the determined system information to wireless device 310A. The system information identifies the position of the RF channel center relative to the synchronization channel. In some cases, the system information may comprise one or more offset values (e.g., one or more frequency offset values). The one or more offset values may include at least a first offset value defining an offset from the synchronization channel part of the RF carrier to a center frequency of the RF carrier. In some cases, the center frequency of the RF carrier may correspond to a carrier raster point of a carrier raster associated with the RF carrier. This system information may also provide the RF channel bandwidth, subcarrier spacing used for the data channels, and other information needed by wireless device 310A to fully acquire and/or continue to set up a connection with the network node. In some cases, the system information may also include information about blanked OFDM subcarriers (e.g., how many subcarriers are blanked, and on what side of the transmission the blanked subcarriers occur). The system information may be transmitted by network node 315A and received by wireless device 310A in any suitable manner. For example, in certain embodiments, the system information may be transmitted in a Master Information Block (MIB), System Information Block (SIB), Remaining Minimum System Information (RMSI), or some combination of the above.
Wireless device 310A obtains the system information for use in determining the position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier. Wireless device 310A may obtain the system information in any suitable manner. As one example, wireless device 310A may receive a system information message including the system information (e.g., MIB, SIB, and/or RMSI). In some cases, at least a portion of the system information may be contained in the PBCH. Based on the obtained system information, wireless device 310A determines the position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier. The process for determining the position of the RF carrier by wireless device 310A is described in more detail below in relation to
In certain embodiments, wireless device 310A may establish a connection with network node 315A via the RF carrier. In some cases, wireless device 310A may receive (e.g., from network node 315A) an instruction to perform a handover to another RF carrier at another frequency.
As noted above, in some cases the position of the RF carrier in the operating band may not be centered within the license block. In such a scenario, wireless device 310A may receive (e.g., from network node 315A) or transmit (e.g., to network node 315A), a truncated transmission of an OFDM symbol. The truncated transmission may include one or more blanked subcarriers on at least one side of the transmission. As noted above, in some cases the obtained system information may include information about blanked subcarriers (e.g., the number of blanked subcarriers and on what side of the transmission the blanked subcarriers are located. This is described in more detail below in relation to
As described above, a wireless device (e.g., wireless device 310A described above in relation to
In certain embodiments, synchronization channel raster points 415 on synchronization channel raster 400 are defined through a 5G-RAN Synchronization Channel Number (GSCN) that defines the frequency FSC of the synchronization channel portion 405 of RF carrier 410. The raster for each operating band is set by a raster point separation ΔFSC,Raster, a first raster point FSC_low and a first raster point number NSC,low. The equation defining the synchronization channel frequency FSC of the raster point number NSC (GSCN) is shown in Equation (1) below:
F
SC
=F
SC,Low
+ΔF
SC,Raster×(NSC−NSC,Low) (1)
Synchronization channel raster 400 is defined as a range of GSCN numbers for each operating band, with the number range starting at NSC,Low.
At initial access, a wireless device does not have any knowledge of the GSCN, but it knows the predetermined raster defined from Equation (1) above. It thereby performs a cell search on those pre-determined raster points.
In certain embodiments, the second step in defining the RF channel frequency identifies the RF channel frequency FCH that is defined in relation to the synchronization channel frequency FSC. In certain embodiments, a 5G-RAN Radio Frequency Channel Offset (GRFCO) defines the offset from the synchronization channel to the RF carrier center frequency. An RF channel raster is defined relative to each point on synchronization channel raster 400 with a separation ΔFCH,Raster between raster points. In certain embodiments, the RF channel can only be positioned on one of the RF channel raster points and its frequency is expressed as an offset relative to the frequency of the synchronization channel, as shown in
The RF channel raster for each Synchronization Channel raster frequency point FSC is set relative to FSC by an RF channel raster point separation ΔFCH,Raster, with a range covering (at least) the full width of the synchronization channel raster separation ΔFSC,Raster. In certain embodiments, the equation defining the RF channel frequency FCH with the offset NCH,Offs (GRFCO) is as shown in Equation (2) below:
F
CH
=F
SC
ΔF
CH,Raster
×N
CH,Offs (2)
In some cases, the wireless device may be provided with the GRFCO from a network node (e.g., network node 315A described above in relation to
In paired spectrum, the GSCN and GRFCO define the DL RF carrier frequency. The UL RF channel frequency has a direct relation to the DL RF channel frequency through a fixed frequency offset with fixed duplex spacing. In cases of variable duplex spacing, the frequency offset between UL and DL can also be provided to the wireless device (e.g., through the system information message or other message).
As described above in relation to
In order to achieve maximum spectrum utilization, a carrier (e.g., RF carrier 410 described above in relation to
In the example of
As shown in
For example, a network node (such as network node 315A described above in relation to
In certain embodiments, the synchronization channel part of the RF carrier may comprise an SS block comprising a PSS and a SSS transmitted together with a PBCH. In certain embodiments, at least a portion of the system information may be contained in the PBCH.
At step 708, the wireless device obtains system information for use in determining a position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier. In certain embodiments, obtaining system information may comprise receiving a system information message.
In certain embodiments, the obtained system information may comprise one or more offset values. In certain embodiments, the one or more offset values may comprise at least a first offset value defining an offset from the synchronization channel part of the RF carrier to a center frequency of the RF carrier. In certain embodiments, the center frequency of the RF carrier may correspond to a carrier raster point of a carrier raster associated with the RF carrier.
At step 712, the wireless device determines, based on the obtained system information, the position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier.
In certain embodiments, the method may comprise determining, based on the obtained system information, one or more of: a bandwidth of the RF carrier; and a subcarrier spacing of one or more data channels. In certain embodiments, the method may comprise establishing a connection with a network node via the RF carrier. In certain embodiments, the method may comprise receiving an instruction to perform a handover to another RF carrier at another frequency.
In certain embodiments, the position of the RF carrier in the operating band may not be centered within a license block, and the method may comprise receiving a truncated transmission of an OFDM symbol. The truncated transmission may comprise one or more blanked subcarriers on at least one side of the transmission. In certain embodiments, the position of the RF carrier in the operating band may not be centered within a license block, and the method may comprise transmitting a truncated transmission of an OFDM symbol. The truncated transmission may comprise one or more blanked subcarriers on at least one side of the transmission.
In certain embodiments, the determined system information may comprise one or more of: a bandwidth of the RF carrier; and a subcarrier spacing of one or more data channels.
In certain embodiments, the synchronization channel part of the RF carrier may comprise an SS block comprising a PSS and a SSS transmitted together with a PBCH.
At step 808, the network node sends the determined system information to the wireless device. In certain embodiments, sending the determined system information to the wireless device may comprise sending at least a portion of the determined system information to the wireless device in the PBCH.
In certain embodiments, the method may comprise establishing a connection with the wireless device via the RF carrier. In certain embodiments, the method may comprise sending an instruction to the wireless device to perform a handover to another RF carrier at another frequency.
In certain embodiments, the position of the RF carrier in the operating band may not be centered within a license block, and the method may comprise receiving a truncated transmission of an OFDM symbol. The truncated transmission may comprise one or more blanked subcarriers on at least one side of the transmission. In certain embodiments, the position of the RF carrier in the operating band may not be centered within a license block, and the method may comprise transmitting a truncated transmission of an OFDM symbol. The truncated transmission may comprise one or more blanked subcarriers on at least one side of the transmission.
Processing circuitry 920 may include any suitable combination of hardware and software implemented in one or more modules to execute instructions and manipulate data to perform some or all of the described functions of wireless device 310, such as the functions of wireless device 310 described above in relation to
Memory 930 is generally operable to store instructions, such as a computer program, software, an application including one or more of logic, rules, algorithms, code, tables, etc. and/or other instructions capable of being executed by processing circuitry 920. Examples of memory 930 include computer memory (for example, Random Access Memory (RAM) or Read Only Memory (ROM)), mass storage media (for example, a hard disk), removable storage media (for example, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or or any other volatile or non-volatile, non-transitory computer-readable and/or computer-executable memory devices that store information, data, and/or instructions that may be used by processing circuitry 920.
Other embodiments of wireless device 310 may include additional components beyond those shown in
Network node 315 may include one or more of transceiver 1010, processing circuitry 1020, memory 1030, and network interface 1040. In some embodiments, transceiver 1010 facilitates transmitting wireless signals to and receiving wireless signals from wireless device 310 (e.g., via antenna 1050), processing circuitry 1020 executes instructions to provide some or all of the functionality described above as being provided by a network node 315, memory 1030 stores the instructions executed by processing circuitry 1020, and network interface 1040 communicates signals to backend network components, such as a gateway, switch, router, Internet, Public Switched Telephone Network (PSTN), core network nodes or radio network controllers 130, etc.
Processing circuitry 1020 may include any suitable combination of hardware and software implemented in one or more modules to execute instructions and manipulate data to perform some or all of the described functions of network node 315, such as those described above in relation to
Memory 1030 is generally operable to store instructions, such as a computer program, software, an application including one or more of logic, rules, algorithms, code, tables, etc. and/or other instructions capable of being executed by processing circuitry 1020. Examples of memory 1030 include computer memory (for example, RAM or ROM), mass storage media (for example, a hard disk), removable storage media (for example, a CD or a DVD), and/or or any other volatile or non-volatile, non-transitory computer-readable and/or computer-executable memory devices that store information.
In some embodiments, network interface 1040 is communicatively coupled to processing circuitry 1020 and may refer to any suitable device operable to receive input for network node 315, send output from network node 315, perform suitable processing of the input or output or both, communicate to other devices, or any combination of the preceding. Network interface 1040 may include appropriate hardware (e.g., port, modem, network interface card, etc.) and software, including protocol conversion and data processing capabilities, to communicate through a network.
Other embodiments of network node 315 may include additional components beyond those shown in
Processing circuitry 1120 may include any suitable combination of hardware and software implemented in one or more modules to execute instructions and manipulate data to perform some or all of the described functions of the radio network controller or core network node 130. In some embodiments, processing circuitry 1120 may include, for example, one or more computers, one or more CPUs, one or more microprocessors, one or more applications, one or more ASICs, one or more FPGAs and/or other logic.
Memory 1130 is generally operable to store instructions, such as a computer program, software, an application including one or more of logic, rules, algorithms, code, tables, etc. and/or other instructions capable of being executed by processing circuitry 1120. Examples of memory 1130 include computer memory (for example, RAM or ROM), mass storage media (for example, a hard disk), removable storage media (for example, a CD or a DVD), and/or or any other volatile or non-volatile, non-transitory computer-readable and/or computer-executable memory devices that store information.
In some embodiments, network interface 1140 is communicatively coupled to processing circuitry 1120 and may refer to any suitable device operable to receive input for the network node, send output from the network node, perform suitable processing of the input or output or both, communicate to other devices, or any combination of the preceding. Network interface 1140 may include appropriate hardware (e.g., port, modem, network interface card, etc.) and software, including protocol conversion and data processing capabilities, to communicate through a network.
Other embodiments of the network node may include additional components beyond those shown in
Determining module 1210 may perform the processing functions of wireless device 310. As one example, determining module 1210 may identify a synchronization channel part of an RF carrier in an operating band. In certain embodiments, determining module 1210 may identify the synchronization channel part of the RF carrier by determining a plurality of pre-determined synchronization raster points based on a synchronization channel raster associated with the synchronization channel part of the RF carrier, each of the pre-determined synchronization raster points defining a possible location of the synchronization channel part of the RF carrier, and performing a cell search on one or more of the plurality of pre-determined synchronization raster points to identify the synchronization channel part of the RF carrier. As another example, determining module 1210 may obtain system information for use in determining a position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier. As still another example, determining module 1210 may determine, based on the obtained system information, the position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier. As yet another example, determining module 1210 may determine, based on the obtained system information, one or more of: a bandwidth of the RF carrier; and a subcarrier spacing of one or more data channels. As another example, determining module 1210 may establish a connection with a network node via the RF carrier. As another example, determining module 1210 may determine that the position of the RF carrier in the operating band is not centered within a license block.
Determining module 1210 may include or be included in one or more processors, such as processing circuitry 920 described above in relation to
Communication module 1220 may perform the transmission functions of wireless device 310. As one example, communication module 1220 may transmit a truncated transmission of an OFDM symbol (e.g., a truncated transmission comprising one or more blanked subcarriers on at least one side of the transmission). Communication module 1220 may include a transmitter and/or a transceiver, such as transceiver 910 described above in relation to
Receiving module 1230 may perform the receiving functions of wireless device 310. For example, receiving module 1230 may obtain system information for use in determining a position of the RF carrier in the operating band relative to the identified synchronization channel part of the RF carrier (e.g., by receiving a system information message). As another example, receiving module 1230 may receive an instruction to perform a handover to another RF carrier at another frequency. As still another example, receiving module 1230 may receive a truncated transmission of an OFDM symbol (e.g., a truncated transmission comprising one or more blanked subcarriers on at least one side of the transmission). Receiving module 1230 may include a receiver and/or a transceiver. Receiving module 1230 may include a receiver and/or a transceiver, such as transceiver 910 described above in relation to
Input module 1240 may receive user input intended for wireless device 310. For example, the input module may receive key presses, button presses, touches, swipes, audio signals, video signals, and/or any other appropriate signals. The input module may include one or more keys, buttons, levers, switches, touchscreens, microphones, and/or cameras. The input module may communicate received signals to determining module 1210. The functions of input module 1240 described above may, in certain embodiments, be performed in one or more distinct modules.
Display module 1250 may present signals on a display of wireless device 310. Display module 1250 may include the display and/or any appropriate circuitry and hardware configured to present signals on the display. Display module 1250 may receive signals to present on the display from determining module 1210. The functions of display module 1250 described above may, in certain embodiments, be performed in one or more distinct modules.
Determining module 1210, communication module 1220, receiving module 1230, input module 1240, and display module 1250 may include any suitable configuration of hardware and/or software. Wireless device 310 may include additional modules beyond those shown in
Determining module 1310 may perform the processing functions of network node 315. As one example, determining module 1310 may determine system information for use by a wireless device to determine a position of an RF carrier in an operating band relative to a synchronization channel part of the RF carrier. As another example, determining module 1310 may establish a connection with the wireless device via the RF carrier. As still another example, determining module 1310 may determine that the position of the RF carrier in the operating band is not centered within a license block. Determining module 1310 may include or be included in one or more processors, such as processing circuitry 1020 described above in relation to
Communication module 1320 may perform the transmission functions of network node 315. As one example, communication module 1320 may send the determined system information to the wireless device (in certain embodiments, by sending at least a portion of the determined system information to the wireless device in the PBCH). As another example, communication module 1320 may send an instruction to the wireless device to perform a handover to another RF carrier at another frequency. As still another example, communication module 1320 may transmit a truncated transmission of an OFDM symbol (e.g., a truncated transmission comprising one or more blanked subcarriers on at least one side of the transmission). Communication module 1320 may transmit messages to one or more of wireless devices 310. Communication module 1320 may include a transmitter and/or a transceiver, such as transceiver 1010 described above in relation to
Receiving module 1330 may perform the receiving functions of network node 315. As one example, receiving module 1330 may receive a truncated transmission of an OFDM symbol (e.g., a truncated transmission comprising one or more blanked subcarriers on at least one side of the transmission). Receiving module 1330 may receive any suitable information from a wireless device. Receiving module 1330 may include a receiver and/or a transceiver, such as transceiver 1010 described above in relation to
Determining module 1310, communication module 1320, and receiving module 1330 may include any suitable configuration of hardware and/or software. Network node 315 may include additional modules beyond those shown in
Modifications, additions, or omissions may be made to the systems and apparatuses described herein without departing from the scope of the disclosure. The components of the systems and apparatuses may be integrated or separated. Moreover, the operations of the systems and apparatuses may be performed by more, fewer, or other components. Additionally, operations of the systems and apparatuses may be performed using any suitable logic comprising software, hardware, and/or other logic. As used in this document, “each” refers to each member of a set or each member of a subset of a set.
Modifications, additions, or omissions may be made to the methods described herein without departing from the scope of the disclosure. The methods may include more, fewer, or other steps. Additionally, steps may be performed in any suitable order.
Although this disclosure has been described in terms of certain embodiments, alterations and permutations of the embodiments will be apparent to those skilled in the art. Accordingly, the above description of the embodiments does not constrain this disclosure. Other changes, substitutions, and alterations are possible without departing from the spirit and scope of this disclosure.
Filing Document | Filing Date | Country | Kind |
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PCT/SE2018/050293 | 3/21/2018 | WO | 00 |
Number | Date | Country | |
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62476380 | Mar 2017 | US |