Real-time signal strength mapping for adaptive uplink combining and spectrum reuse in a ran multicast

Abstract

A RAN has a plurality of O-RUs that may operate for the same cell. A DU has a plurality of fronthaul receivers. The fronthaul receiver receives 7.2x packet data from each of the O-RUs and reconstructs a resource grid for each. An upper PHY module receives the resource grids, extracts signal strength information pertaining to each UE, and compares each signal strength to a threshold. The upper PHY module then generates a bitmap that maps the UEs that have a signal strength above the threshold. For a UE that has signal strengths above the threshold for two or more remote units, a scheduler instructs the upper PHY layer to combine those resource blocks. For any instance in which a UE has one or more signal strengths that are below the threshold, the scheduler instructs the scheduler to perform spectrum reuse.

Description

Real-Time Signal Strength Mapping for Adaptive Uplink Combining and Spectrum Reuse in a RAN Multicast.BACKGROUND OF THE INVENTION

[0001] Conventional 5G NR (New Radio) or 4G LTE RAN (Radio Access Network) systems may involve a Central Unit (CU), a Distributed Unit (DU) that is coupled to the CU, and a plurality of Remote Units (RUs) that are coupled to the DU. The multiple RUs may operate for the same cell, namely shared cell operation, whereby each of the RUs use the same carrier frequencies and some of the RUs may cover overlapping areas.

[0002] Such RANs may broadcast a single signal in the Downlink (DL) such that all the RUs receive the same signal from the DU and broadcast it accordingly. However, for the Uplink (UL), each RU may not receive the same signals from its connected User Equipment (UEs) because the RUs may have different coverage areas (hereafter referred as zones) and may have different channel conditions. Accordingly, even though a single signal is broadcast by all of the RUs for the Downlink, each RU may receive a unique signal in the uplink from each UE Under conventional operation, whereas the DU receives a single signal in the uplink, which is the combination of the signals coming from all of the RUs in the shared cell coverage area.

[0003] Conventional shared cell operation has several deficiencies. In particular, the broadcasting of a single stream in the DL and the conventional signal combining in the UL, does not allow spectrum reuse in either.

[0004] In addition, conventional uplink combining may degrade the overall quality (including the signal-to-noise-ratio) of the received signal. In particular, summing the signal from every RU sums the noise from each of them, increasing the overall noise floor and thus degrading the overall signal to noise ratio.

[0005] Accordingly, what is needed is a RAN that is capable of one or more RUs sharing a cell, in which a DU that receives signals from the same UEs through multiple RUs can selectively and / or coherently combine their respective uplink signals, and RUs that have exclusive connections to other UEs may be allocated resource elements such that multiple RUs may each service distinct UEs using the same resources within the cell.SUMMARY OF THE INVENTION

[0006] An aspect of the present disclosure involves a method for processing UE (User Equipment) uplink (UL) signals in a RAN (Radio Access Network). The method comprises receiving a first UL signal data from a first remote unit and receiving a second UL signal data from a second remote unit. The method then involves deriving a first signal strength from the first UL signal data, the first signal strength corresponding to a first UE; deriving a second signal strength from the second UL signal data, the second signal strength corresponding to the first UE; deriving a third signal strength from the first UL signal data, the third signal strength corresponding to a second UE; and deriving a fourth signal strength from the second UL signal data, the fourth signal strength corresponding to the second UE. Each of the first, second, third and fourth signal strengths are compared to a threshold. Then a first plurality of resource blocks are reconstructed from the first UL signal data corresponding to the first UE, and a second plurality of resource blocks are reconstructed from the second UL signal data corresponding to the first UE. The first and second resource blocks are combined based on both the first signal strength and the second signal strength being above the threshold, and spectrum reuse is performed based on the first signal strength being below the threshold and the third signal strength being above the threshold.

[0007] Another aspect of the present disclosure involves a method for processing UE (User Equipment) uplink UL signals in a RAN. The method comprises receiving first UL signal data from a first remote unit first antenna, receiving second UL signal data from a first remote unit second antenna, receiving a third UL signal data from a second remote unit first antenna, and receiving a fourth UL signal data from a second remote unit second antenna. The method then involves deriving a first signal strength from the first UL signal data, the first signal strength corresponding to a first UE; deriving a second signal strength from the second UL signal data, the second signal strength corresponding to the first UE; deriving a third signal strength from the third UL signal data, the third signal strength corresponding to the first UE; and deriving a fourth signal strength from the fourth UL signal data, the fourth signal strength corresponding to the first UE. Each of the first, second, third and fourth signal strengths are then compared to a threshold. A first plurality of resource blocks are then reconstructed from the first UL signal data corresponding to the first UE, a second plurality of resource blocks are reconstructed from the second UL signal data corresponding to the first UE, a third plurality of resource blocks are reconstructed from the third UL signal data corresponding to the first UE, and a fourth pluralityof resource blocks are reconstructed from the fourth UL signal data corresponding to the first UE. The resource blocks corresponding to the first UE that have a signal strength greater than the threshold are combined, and spectrum reuse is performed on the resource blocks that have a signal strength less than the threshold.BRI EF DESCRI PTION OF DRAWI NGS

[0008] FIG. 1 illustrates an exemplary RAN that performs selective uplink combining and spectrum reuse according to the disclosure.

[0009] FIG. 2 illustrates an exemplary process for performing selective uplink combining and spectrum reuse according to the disclosure.

[0010] FIG. 3A illustrates an exemplary bitmap for the RAN shown in FIG. 1, in which each IORAN has a single antenna.

[0011] FIG. 3B shows the exemplary bitmap of FIG. 3A but with zones superimposed.

[0012] FIG. 3C illustrates an exemplary pair of bitmaps, one for cell having two zones, and one for a cell 2 having a single zone.

[0013] FIG. 4A illustrates an exemplary bitmap for the RAN shown in FIG. 1, in which each O- RAN has two antennas.

[0014] FIG. 4B shows the exemplary bitmap of FIG. 4A but with zones superimposed.DETAI LED DESCRIPTION OF TH E I NVENTION

[0015] FIG. 1 illustrates an exemplary RAN configuration 100 according to the disclosure.Exemplary RAN configuration 100 is depicted as a 5G NR (New Radio) implementation according to the O-RAN (Open-RAN) specification, showing logical connections. RAN configuration 100 has an O-DU (O-RAN Distributed Unit) 105 that may be coupled to an O-CU (O-RAN Centralized Unit - not shown) over an Fl interface 112. O-DU 105 may have a network interface module 110 that couples the Fl interface 112 to a 5G protocol stack segment having an RLC (Radio Link Control) layer module 115; a MAC (Medium Access Control) layer module 120; and an upper PHY (Physical) layer module 125. The functions of RLC layer 115 and MAC layer module 120 may provide an implementation of the O-DU and 5G specifications. Upper PHY module 125 may implement upper physical layer processing according to the O-DU and 5G specifications. Upper PHY module 125 may be connected to fronthaul receivers 135a, 135b, and 135c over an internal bus 127. Upper PHY module 125 may also be connected to a zone manager 119. Also within DU105 is a scheduler module 123, which is coupled to PHY module 125, MAC layer module 120, and zone manager 119. The function of the zone manager 119 and scheduler module 123 is described below.

[0016] Fronthaul receiver 135a may be coupled to O-RU 145a over a logical connection 137a; fronthaul receiver 135b may be coupled to O-RU 145b over a logical connection 137b; and Fronthaul receiver 135c may be coupled to O-RU 145c over a logical connection 137c. Each of the logical connections 137a-c may be implemented over, for example, an Ethernet network using an eCPRI (enhanced Common Public Radio Interface). The Ethernet network may include a switch (not shown) for routing uplink 7.2x packets (as defined in the O-RAN specification) from each O-RU 145a / b / c to its respective fronthaul receiver 135. The use of logical connections 137a / b / c are for illustrative purposes and intended to show the topology of connections between fronthaul receivers 135a / b / c and O-RUs 145a / b / c.

[0017] Fronthaul receiver 135a / b / c may be collectively referred to as specific implementations of a fronthaul receiver 135a / b / c. Although three fronthaul receivers 135 are illustrated and discussed in this example, it will be understood that more fronthaul receivers 135 are possible and within the scope of the disclosure. Similarly, O-RU 145a, O-RU 145b, and O-RU 145c may be referred to as a specific instance of an O-RU 145. Although three O-RUs 145 are illustrated in FIG. 1, it will be understood that more O-RUs 145 are possible and within the scope of the disclosure.

[0018] Each of fronthaul receivers 135 may include one or more software modules that does the following: receives packetized 7.2x data from the O-RU 145 to which it is coupled; depacketizes the received 7.2x data; decompresses the depacketized data (if data compression is enabled); converts the decompressed depacketized data from integer format to floating point format into l / Q (In-phase / Quadrature) samples; and reconstructs a resource grid of I / O samples (one for each physical antenna coupled to each O-RU 145a / b / c) for subsequent processing by upper PHY module 125.

[0019] Each O-RU 145 may have one or more processors and software modules (not shown) for implementing lower PHY layer functionality defined by the O-RAN and 5G specifications. Each O- RU 145 may also have the necessary radio components and antennas (not shown) to transmit and receive RF (Radio Frequency) signals over the air. Further, each O-RU 145 may have one or more antennas (not shown). An O-RU 145 with MIMO (Multiple Input Multiple Output)capability will have multiple antennas, each corresponding to an independent signal, and thus each having its own dedicated resource grid for uplink and downlink.

[0020] As illustrated, O-RU 145a has a coverage area 150a; O-RU 145b has a coverage area 150b; and O-RU 145c has a coverage area 150c. O-RUs 145a / b are configured to operate for a single cell (Cell 1). In sharing a cell, O-RU 145a and O-RU 145b have overlapping coverage areas and transmit and receive on the same carrier frequencies. In the following, the coverage areas 150a and 150b for the Cell 1 operated by O-RUs 145a and 145b, will be also referred to as zones. O-RU 145c is configured to operate for a different cell (Cell 2).

[0021] As illustrated, coverage areas 150a / b / c may have overlapping and non-overlapping regions. For example, cell coverage area 150a of O-RU 145a has a connection with UE1, UE2, UE3, UE4, and UE5, whereby it has exclusive connection with UE1 and UE2; and O-RU1 145a also shares connection to UE3, UE4, UE5 and with O-RU 145b. O-RU 145c shares coverage of UE7 with O-RU 145b, and has exclusive coverage with UE8, UE9, and UE10.

[0022] Zone manager module 119 defines the topology of the shared cells and zones. In particular, it identifies the set of O-RUs that operate for the same cell. For example, O-RUs 145a and 145b operate for Cell 1, and the O-RU 145c operates for Cell 2. Although exemplary RAN configuration 100 includes three O-RUs 145 operating for two cells (Cell 1 and Cell 2), it will be understood that RAN according to the disclosure may have many O-RUs 145 that may define a complex topology of cells, some of which may have a single O-RU 145, and others may have two, three, or more O-RUs 145, in which some of their respective coverage areas may converge with different extents of overlap. Zone manager 119 defines these relationships and provides this information to scheduler module 123. In addition, the zone manager module 119 receives UE signal strength information (e.g., the SINR) for each zone from the upper PHY module 125. This information is further processed and provided as a bitmap to scheduler module 123, as described below. Zone manager 119 may be accessed by a user interface (not shown) whereby a user may reconfigure RAN 100 to meet a change in demand for connectivity, or a change in the radio environment in which RAN 100 is deployed.

[0023] Scheduler module 123 may be implemented all or partly within MAC layer module 120, or may be a standalone software module. Scheduler module 123 receives zone information and bitmap information from zone manager 119; and resource grid data from upper PHY module 125. Scheduler module 123 uses this information to identify clusters of UEs that are served on the same set of zones. UEs from different clusters are served by different zones and may beavailable for spectrum reuse for both UL and DL. The set of UEs served by more than one zone may be available for selective uplink combining. The specifics of this process are described below.

[0024] All of the component modules (for example, interface 110, RLC layer module 115, MAC layer module 120, upper PHY module 125, zone manager 119, scheduler module 123, fronthaul receivers 135a / b / c, and the lower PHY layer modules of O-RUs 145a / b / c), and the use of the term "module" herein, may refer to a set of machine-readable instructions that are encoded within one or more non-transitory memory devices and executed on one or more processors that host O-DU 105 and O-RUs 145a / b / c. As used herein, the term "non-transitory memory" may refer to any tangible storage medium (as opposed to an electromagnetic or optical signal) and refer to the medium itself, and not to a limitation on data storage (e.g., RAM vs. ROM). For example, non-transitory medium may refer to an embedded memory that is encoded with instructions whereby the memory may have to be re-loaded with the appropriate machine- readable instructions after being power cycled. Each of the modules disclosed herein may be hosted on one or more processors within O-DU 105 and each of the O-RUs 145a / b / c. It will be understood that variations to the how these modules are deployed on a hardware compute environment are possible and within the scope of the disclosure.

[0025] Further, if an action is described herein as being done by a referenced module (e.g., "e.g., fronthaul receiver 135a combines the signals ..."), it will be understood that this may describe one or more processors executing the module's machine-readable instructions to perform the particular action.

[0026] Also, as used herein, "spectrum resources" may refer to a given set of resource blocks within a resource grid and over one spatial dimension. Further, a single UE may be allocated one or more resource blocks. A resource block may have multiple l / Q samples. For example, under 4G, a resource block has 12 subcarriers times the number of 14 OFDM symbols, whereas in 5G a resource block has 12 subcarriers regardless of the number of OFDM symbols.

[0027] Exemplary RAN configuration 100 may operate as follows. In the Uplink, each O-RU 145 receives signals from UEs within its coverage area. Each of the O-RUs 145 performs RF (Radio Frequency) reception and lower PHY processing on received signals from each of its antennas (if O-RU 145 has MIMO capability) to generate a plurality of digitized samples representing the baseband signal from each antenna. O-RU 145 generates packetized 7.2x data encapsulating the digitized samples.

[0028] For exemplary RAN configuration 100, O-RU 145a receives and does lower PHY processing on uplink signals from UE1, UE2, UE3, UE4, and UE5, as received by each of its antennas, converts the signals into packetized 7.2x data, and transmits the packetized 7.2x data to fronthaul receiver 135a over logical connection 137a. O-RU 145b receives and does lower PHY processing on uplink signals from UE3, UE4, UE5, UE6, and UE7, as received by each of its antennas, converts the signals into packetized 7.2x data, and transmits the packetized 7.2x data to fronthaul receiver 135b over logical connection 137b. O-RU3 145c receives and does lower PHY processing on uplink signals from UE7, UE8, UE9, and UE10, as received by each of its antennas, converts the signals into packetized 7.2x data, and transmits the packetized 7.2x data to fronthaul receiver 135c over logical connection 137c.

[0029] Fronthaul receiver 135a receives the 7.2x data packets from O-RU 145a, depacketizes the received 7.2x data; decompresses the depacketized data (if data compression is enabled; converts the decompressed depacketized data from integer format to floating point format into l / Q (In-phase / Quadrature) samples; and reconstructs a resource grid of I / O samples. Here, each reconstructed resource grid has resource blocks with l / Q sample data from UE1, UE2, UE3, UE4, and UE5. There is one resource grid from each antenna coupled to O-RU 145a. Fronthaul receiver 135a reconstructs one resource grid for each antenna connected to O-RU 145a.

[0030] Fronthaul receiver 135b receives the 7.2x data packets from O-RU 145b, depacketizes the received 7.2x data; decompresses the depacketized data (if data compression is enabled; converts the decompressed depacketized data from integer format to floating point format into l / Q (In-phase / Quadrature) samples; and reconstructs a resource grid of l / Q samples. Here each reconstructed resource grid has resource blocks with l / Q sample data from UE3, UE4, UE5, UE6, and UE7. There is one resource grid from each antenna coupled to O-RU 145b. Fronthaul receiver 135b reconstructs one resource grid for each antenna connected to O-RU 145b.

[0031] Fronthaul receiver 135c receives the 7.2x data packets from O-RU 145c, depacketizes the received 7.2x data; decompresses the depacketized data (if data compression is enabled; converts the decompressed depacketized data from integer format to floating point format into l / Q (In-phase / Quadrature) samples; and reconstructs a resource grid of l / Q samples. Here each reconstructed resource grid has resource blocks with l / Q sample data from UE7, UE8, UE9, and UE10. There is one resource grid from each antenna coupled to O-RU 145c. Fronthaul receiver 135c reconstructs one resource grid for each antenna connected to O-RU 145c.

[0032] FIG. 2 illustrates an exemplary process 200 for performing selective uplink combining and spectrum reuse according to the disclosure. Steps 205-210 may be performed by fronthaul receiver 135a, step 215 may be performed by upper PHY module 125, steps 220-232 may be performed by zone manager 119, and steps 235-245 may be performed by scheduler module 123.

[0033] Process 200 is described in the context of exemplary RAN 100, in which O-RU 145a and O-RU 145b (both as zones) operate for the same cell (Cell 1). It will be understood that the process may also apply to different and more complex topologies.

[0034] In step 205, fronthaul receiver 135a receives 7.2x packet data from O-RU 145a over logical connection 137a; fronthaul receiver 135b receives 7.2x packet data from O-RU 145b over logical connection 137b; and fronthaul receiver 135c receives 7.2x packet data from O-RU 145c over logical connection 137c.

[0035] In step 210, fronthaul receiver 135a depacketizes its received 7.2x data; decompresses the depacketized data (if data compression is enabled); converts the decompressed depacketized data from integer format to floating point format into l / Q. (In-phase / Quadrature) samples; and reconstructs a resource grid of l / Q samples for each antenna of O-RUs 145a, thereby reconstructing resource blocks for each of UE1, UE2, UE3, UE4, and UE5. Fronthaul receiver 135b depacketizes its received 7.2x data; decompresses the depacketized data (if data compression is enabled); converts the decompressed depacketized data from integer format to floating point format into l / Q (In-phase / Quadrature) samples; and reconstructs a resource grid of l / Q samples for each antenna of O-RUs 145b, thereby reconstructing resource blocks for each of UE3, UE4, UE5, UE6, and UE7. Fronthaul receiver 135c depacketizes its received 7.2x data; decompresses the depacketized data (if data compression is enabled); converts the decompressed depacketized data from integer format to floating point format into l / Q (In- phase / Quadrature) samples; and reconstructs a resource grid of l / Q samples for each antenna of O-RUs 145c, thereby reconstructing resource blocks of each of UE7, UE8, UE9, and UE10.

[0036] Further to step 210, fronthaul receivers 135a-135c provide their respective resource grids to upper PHY module 125.

[0037] In step 215, upper PHY module 125 determines the signal strength observed by each O-RU 145 from the UEs connected to their serving cell. It may do this by extracting a signal strength metric for each UE using channel and SNR estimation. In an example, upper PHY module 125 may extract the SINR (Signal to Interference plus Noise Ratio) observed by O-RU 145for each UE. In addition, the upper PHY module 125 provides the signal strength (e.g. SINR) information for each O-RU 145 to the zone manager 119.

[0038] In step 220, zone manager 119 compares the signal strengths derived in step 215 (e.g., SINR) to a preset threshold. Accordingly, the signal strengths corresponding to each UE observed by O-RU 145a-145c are determined to be either below or above the threshold. The threshold may be a preconfigured value, which may be provided by a user interface (not shown).

[0039] In step 225, zone manager 119 generates a bitmap corresponding to the signal strengths of step 215 filtered by the threshold in step 220. For example, the bitmap may be a matrix A of bits, where the element aL Jis the bitmap element for the UE i and resource grid j in a given O- RU 145. In an example, the bitmap element j is set to zero if the signal strength of the UE i observed on resource grid j is below the threshold; and set to one otherwise. In doing so, zone manager 119 compares the threshold against the signal strength metric for each UE in each resource grid (one per antenna) for each O-RU 145. The zone manager 119 correlates the resource grids to its corresponding antenna and O-RU 145 by means of an eAxC (extended Antenna Carrier identifier) index.

[0040] Accordingly, for a given set of resource blocks, the bitmap may have one matrix of bits per antenna stream from each O-RU 145.

[0041] FIG. 3A illustrates an exemplary bitmap 300, in which each O-RU 145 has a single antenna. As illustrated, each UE is represented for each O-RU 145 by a binary indication that the SNR for that UE is above or below a predefined threshold.

[0042] FIG. 3B illustrates a bitmap 300 in which each of the O-RUs has only one antenna. Shown are zone map 305, which operates for Cell 1 in RAN 100; and zone map 310, which operates for Cell 2 in RAN 100.

[0043] FIG. 3C illustrates an exemplary pair of bitmaps, one for Cell 1 (350a) having two zones 150a / b, and one for Cell 2 (350b) having a single zone 150c. As illustrated, each UE is represented for each zone 150 by a binary indication that the SNR for that UE is above a predefined threshold.

[0044] FIG. 4A illustrates an exemplary bitmap 400, which pertains to exemplary RAN 100, but in which each O-RU 145 has two antennas. Further illustrated in FIG. 4A is a scenario in which different UEs may be connected not only to one of the two antennas of its corresponding O-RU but also to other O-RUs. For example, UE5 has a bitmap 415 indicating that it is connected only to the first antenna of O-RU 145a, and to both the antennas from O-RU 145b. UE3 has a bitmap420 indicating that it is connected to the second antenna of O-RU 145b and to both antennas from O-RU 145a. And UE 10 has a bitmap 425 indicating that it is only connected to the first antenna of O-RU 145c but not to the second. This is a possible scenario that would be identified in step 225.

[0045] FIG. 4B illustrates a bitmap 400 in which each of the O-RUs has two antennas. Similarly to FIG. 3B, shown are zone map 405, which defines Cell 1 in RAN 100; and zone map 410, which operates for Cell 2 in RAN 100.

[0046] Returning to process 200, in step 230, zone manager 119 provides the bitmap to scheduler module 123. It may do so using inter-process data communications.

[0047] In step 232, zone manager 119 provides zone mapping information to scheduler module 123. The zone mapping information indicates the set of O-RUs 145 operating for the same cell. In exemplary RAN 100, O-RU 145a and O-RU 145b operate for the same cell (Cell 1) and define the two zones 150a and 150b, and O-RU 145c operates for a single cell (Cell 2), thus defining only one zone 150c.

[0048] In step 235, scheduler module 123 uses the bitmap generated in step 225 and the zone mapping from zone manager 119 in step 232 to designate candidate of UEs for spectrum reuse and the set of resource blocks to be used for selective combining.

[0049] The following description of steps 235-240 applies to the scenario in which each of the O-RUs 145 in RAN 100 has only one antenna (FIGs. 3A, 3B, and 3C).

[0050] In step 235, scheduler module 123 identifies the pattern in bitmap 300 where it is observed that UE1 and UE2 are under the exclusive coverage of the zone 150a; that UE3, UE4, and UE5 are under the coverage area of the zones 150a and 150b; that UE 6 is exclusively covered by the zone 150b; UE7 is covered by zones 150b and 150c; and that UE8-10 are exclusively covered by zone 105c

[0051] Scheduler module 123 takes the following actions in step 240.

[0052] For UE3-5, scheduler module 123 instructs upper PHY module 125 to perform selectiveUL combining of the l / Q. samples provided by O-RUs 145a and 145b, for the resource blocks respectively assigned to UE3, UE4, and UE5.

[0053] Since UE1-2 and UE6-7 are served under different zones (150a, and 150b, respectively within Cell 1), they form two clusters of UEs (one composed of UE1-2, served under zone 150a, and the other of UE6-7, served under zone 150b), which can be scheduled in the same resources, thus performing spectrum reuse. In particular, the scheduler module 123 marks theresources blocks allocated to UE1 and UE2 for spectrum reuse with UE6 and UE7, but not for spectrum reuse with UE3-5.

[0054] For UE8-10, scheduler module 123 identifies them as exclusively connected to O-RU 145c and that there is no opportunity for selective combining or spectrum reuse.

[0055] UE7 is within the coverage of both O-RU 145b (zone 150b) and O-RU 145c (zone 150c) but will be served only by the O-RU related to the cell in which is camped. In the example, UE7 is camped in Cell 1, thus referring to O-RU 145b.

[0056] The following description of steps 235-240 applies to the scenario in which each of the O-RUs 145 in RAN 100 has two antennas.

[0057] In step 235, scheduler module 123 identifies the pattern in bitmap 400.

[0058] Scheduler module 123 takes the following actions in step 240.

[0059] For UE1-2, scheduler module 123 instructs upper PHY module 125 to combine the l / Q samples for the resource blocks assigned to the first antenna and second antenna of O-RU 145a. Scheduler module 123 may also instruct MAC layer 120 to perform spectrum reuse with UE1-2 with O-RU 145a and UE6-7 with O-RU 145b.

[0060] For UE3, scheduler module 123 instructs upper PHY module 125 to combine the l / Q samples for the resource blocks assigned to the first antenna and second antenna of O-RU 145a and the second antenna of O-RU 145b.

[0061] For UE4, scheduler module 123 instructs upper PHY module 125 to combine the l / Q samples for the resource blocks assigned to the first antenna, second antenna of O-RU 145a, first antenna of O-RU 145b, and second antenna of O-RU 145b.

[0062] For UE5, scheduler module 123 instructs upper PHY module 125 to combine the l / Q samples for the resource blocks assigned to the first antenna and second antenna of O-RU 145b and the first antenna of O-RU 145a.

[0063] For UE6-7, scheduler module 123 instructs upper PHY module 125 to combine the l / Q samples for the resource blocks assigned to the first antenna and second antenna of O-RU 145b. Scheduler module 123 also instructs UE 6-7 for spectrum reuse with other UEs exclusively connected to cell 1 and served by a different zone.

[0064] For UE8-9, scheduler module 123 instructs upper PHY module 125 to combine the l / Q samples for the resource blocks assigned to the first antenna and second antenna of O-RU 145c.

[0065] For UE10, scheduler module 123 instructs upper PHY module 125 to not combine the l / Q samples for the resource blocks assigned to the first antenna and second antenna of O-RU145c. In doing so, scheduler module 123 may simply not instruct upper PHY module 125 to do anything regarding UE10.

[0066] In step 245, the scheduler module 123 receives the resource grid information from upper PHY module 125, including those resource blocks that have been combined in step 240. Scheduler module 123 then performs scheduling, including spectrum reuse on the resource blocks identified by scheduler module 123 in step 240. MAC layer module 120 may implement spectrum reuse for both the uplink and the downlink processes

[0067] Process 200 is iterative and may be performed once every TTI (Transmission Time Interval), or as frequently as SNR data is provided by the UEs. It will be understood that, for the first iteration of process 200, the bitmap is undetermined. Accordingly, the bitmap may be initialized with all "ones", as if all the received signals are above the pre-configured threshold.

[0068] Variations to the disclosed RAN 100 are possible. For example, if there are three or more O-RUs sharing a cell, and the corresponding resource blocks have a mix of signals above and below the threshold (e.g., [1,1,0] with three O-RUs), then scheduler module 123 may perform uplink combining with two O-RUs having resource grids corresponding to the 1,1 values, and may perform spectrum reuse for the remaining O-RU that had the resource grid with the zero value. It will be understood that such variations are possible and within the scope of the disclosure.

[0069] It will be understood that the above description may also apply to an LTE (Long Term Evolution) RAN and that such variations are within the scope of the disclosure.

[0070] Accordingly, disclosed exemplary process 200 may more efficiently and effectively identify opportunities both for spectrum reuse and for uplink combining, thereby improving spectrum efficiency as well as improving RAN performance.

Claims

Claims1. A method for processing UE (User Equipment) uplink (UL) signals in a RAN (Radio Access Network), the method comprising: receiving a first UL signal data from a first remote unit; receiving a second UL signal data from a second remote unit; deriving a first signal strength from the first UL signal data, the first signal strength corresponding to a first UE; deriving a second signal strength from the second UL signal data, the second signal strength corresponding to the first UE; deriving a third signal strength from the first UL signal data, the third signal strength corresponding to a second UE; deriving a fourth signal strength from the second UL signal data, the fourth signal strength corresponding to the second UE; comparing the first signal strength to a threshold; comparing the second signal strength to the threshold; comparing the third signal strength to the threshold; comparing the fourth signal strength to the threshold; reconstructing a first plurality of resource blocks from the first UL signal data corresponding to the first UE; reconstructing a second plurality of resource blocks from the second UL signal data corresponding to the first UE, combining the first and second resource blocks based on both the first signal strength and the second signal strength being above the threshold, and performing spectrum reuse based on the first signal strength being below the threshold and the third signal strength being above the threshold.

2. The method of claim 1, wherein reconstructing the first plurality of resource blocks from the first UL signal data comprises identifying the first plurality of resource blocks from a first resource grid reconstructed from the first UL signal data, and wherein reconstructing the second plurality of resource blocks from the second UL signal data comprises identifying the second plurality of resource blocks from a second resource grid reconstructed from the second UL signal data.

3. The method of claim 1, wherein the first remote unit and the second remote unit are operating on the same cell.

4. The method of claim 1, further comprising generating a bitmap, the bitmap comprises:a first bit indicating whether the first signal strength is above the threshold; and a second bit indicating whether the second signal strength is above the threshold.

5. The method of claim 1, wherein performing spectrum reuse comprises spectrum reuse for uplink signals and downlink signals.

6. The method of claim 1, wherein the RAN comprises an O-RAN (Open-RAN) implementation.

7. The method of claim 1, wherein the receiving a first signal data from a first remote unit comprises receiving 7.2x packet data.

8. The method of claim 1, wherein the deriving a plurality of first signal strengths comprises deriving a SINR (Signal to Interference plus Noise Ratio) corresponding to the first UE.

9. The method of claim 1, wherein the combining the first and second resource blocks if both the first signal strength and the second signal strength comprises instructing an upper PHY layer to combine the first and second resource blocks.

10. The method of claim 9, wherein the combining the first and second resource blocks if both the first signal strength and the second signal strength are above the threshold, comprises combining corresponding l / Q. (In phase / Quadrature) samples of the first and second resource blocks.

11. The method of claim 1, wherein the performing spectrum reuse on the first plurality of resource blocks comprises instructing a MAC (Medium Access Control) layer to perform spectrum reuse of the first plurality of resource blocks.

12. A method for processing UE (User Equipment) uplink UL signals in a RAN, the method comprising: receiving first UL signal data from a first remote unit first antenna; receiving second UL signal data from a first remote unit second antenna; receiving a third UL signal data from a second remote unit first antenna; receiving a fourth UL signal data from a second remote unit second antenna; deriving a first signal strength from the first UL signal data, the first signal strength corresponding to a first UE; deriving a second signal strength from the second UL signal data, the second signal strength corresponding to the first UE; deriving a third signal strength from the third UL signal data, the third signal strength corresponding to the first UE; deriving a fourth signal strength from the fourth UL signal data, the fourth signal strength corresponding to the first UE; comparing the first signal strength to a threshold; comparing the second signal strength to the threshold; comparing the third signal strength to the threshold; comparing the fourth signal strength to the threshold; reconstructing a first plurality of resource blocks from the first UL signal data corresponding to the first UE; reconstructing a second plurality of resource blocks from the second UL signal data corresponding to the first UE;reconstructing a third plurality of resource blocks from the third UL signal data corresponding to the first UE; reconstructing a fourth plurality of resource blocks from the fourth UL signal data corresponding to the first UE; combining the resource blocks corresponding to the first UE that have a signal strength greater than the threshold; and performing spectrum reuse on the resource blocks that have a signal strength less than the threshold.

13. The method of claim 12 wherein the performing spectrum reuse comprises performing spectrum reuse for uplink and downlink.

14. The method of claim 12 further comprising: reconstructing a first resource grid from the first signal data, and deriving the first signal strength from the first resource grid; reconstructing a second resource grid from the second signal data, and deriving the second signal strength from the second resource grid; reconstructing a third resource grid from the third signal data, and deriving the third signal strength from the third resource grid; and reconstructing a fourth resource grid from the fourth signal data, and deriving the fourth signal strength from the fourth resource grid.

15. The method of claim 12, wherein the first and second remote units operate on the same cell.

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