Patent Description:
Spectrum sharing is a promising technology that allows operators to make use of current <NUM>rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) wireless communication radio spectrum (referred to generally herein as "spectrum") bands to migrate <NUM>th Generation (<NUM>) (also called "New Radio (NR)") applications without the extra costs of acquiring new <NUM> NR spectrum or <NUM> radio and baseband hardware. Spectrum sharing allows LTE and NR to coexist and share operations in a single band with a minimum impact on the LTE side.

The spectrum sharing techniques adopted between NR and LTE radio access technologies (RATs) may be implemented on a static frequency division multiplexing (FDM) or time division multiplexing (TDM) basis, as well as dynamic or instantaneous sharing on a TDM basis. The spectrum sharing between LTE and NR transmissions may be managed by avoiding the collision with LTE dedicated signals including Cell-specific Reference Signals (CRS), and sync block signals, e.g., primary synchronization signals (PSS) and secondary synchronization signals (SSS). This can be done by re-allocating NR signals or rate matching around the always-transmitted LTE signals.

Alternately, to rate match around LTE dedicated signals, e.g., LTE PSS/SSS, it is possible to use resource block (RB) and symbol level granularity to define specific patterns in the time/frequency domain that are repeated with a specific periodicity. These block-based patterns may be are expressed by two bit maps; namely, a frequency domain bit map with granularity of one RB and a time domain bit map with granularity of one orthogonal frequency-division multiplexing (OFDM) symbol.

Uplink (UL) sounding reference signals (SRS) may be exploited by the base station for channel-state estimation to enable uplink channel-dependent scheduling and link adaptation. The SRS can also be used in other cases such as helping the network to be able to estimate the uplink receive timing as part of the uplink-timing-alignment procedure.

SRS is a frequency-domain reference-signal sequence that is defined by cyclic shifts of prime-length Zadoff Chu (ZC) sequences for sequence lengths equal to M, e.g., <NUM> in LTE. A ZC sequence, also referred to as a Chu sequence or Frank-Zadoff-Chu (FZC) sequence, is a complex-valued mathematical sequence which, when applied to a signal, gives rise to a new signal of constant amplitude. When cyclically shifted versions of a Zadoff-Chu sequence are imposed upon a signal the resulting set of signals detected at the receiver are uncorrelated with one another. The length of the sequence M is defined by the SRS bandwidth, which is a multiple of <NUM> physical resource blocks (PRBs). SRS is mapped to every second, or fourth subcarrier, creating a "comb"-like spectrum, i.e., comb level <NUM> or comb level <NUM>. Maximum cyclic shifts are <NUM> for a comb <NUM> and <NUM> for a comb <NUM>.

For implementation of SRS functionality, in some configurations, NR utilizes the same SRS format as LTE. Specifically, there are <NUM> LTE configurations from <NUM> possible configurations in the range of (<NUM>, <NUM>) physical resource blocks (PRBs). For a bandwidth (BW) <= <NUM> PRBs, there are the same <NUM> LTE configurations and <NUM> new ones. For the bandwidth configurations between <NUM> < BW <= <NUM>, <NUM> new configurations are introduced for NR.

For spectrum sharing between NR and LTE, separate SRS processes may have to be implemented for each of LTE and NR resulting in less efficient use of available PRB's in the uplink (UL) shared spectrum (i.e., additional SRS-PRBs, based on the configured SRS-Bandwidth will be required for over-the-air transmission).

Document <CIT> relates to a communication scheme and system for converging a 5th generation (<NUM>) communication system for supporting a data rate higher than that of a 4th generation (<NUM>) system.

Before describing in detail exemplary embodiments, it is noted that the embodiments reside primarily in combinations of apparatus components and processing steps related to supporting spectrum sharing between LTE and NR that allows a common set of SRS sequences to be assigned to LTE or NR WD's, reducing the number of PRBs that have to be reserved for sounding and may instead use the PRBs to allocate more PUSCH and PUCCH. Accordingly, components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

The term "network node" used herein can be any kind of network node comprised in a radio network which may further comprise any of base station (BS), radio base station, base transceiver station (BTS), base station controller (BSC), radio network controller (RNC), g Node B (gNB), evolved Node B (eNB or eNodeB), Node B, multi-standard radio (MSR) radio node such as MSR BS, multi-cell/multicast coordination entity (MCE), integrated access and backhaul (IAB) node, relay node, donor node controlling relay, radio access point (AP), transmission points, transmission nodes, Remote Radio Unit (RRU) Remote Radio Head (RRH), a core network node (e.g., mobile management entity (MME), self-organizing network (SON) node, a coordinating node, positioning node, MDT node, etc.), an external node (e.g., 3rd party node, a node external to the current network), nodes in distributed antenna system (DAS), a spectrum access system (SAS) node, an element management system (EMS), etc. The network node may also comprise test equipment. The term "radio node" used herein may be used to also denote a wireless device (WD) such as a wireless device (WD) or a radio network node.

Other wireless systems, including without limitation Wide Band Code Division Multiple Access (WCDMA), Worldwide Interoperability for Microwave Access (WiMAX), Ultra Mobile Broadband (UMB) and Global System for Mobile Communications (GSM), may also benefit from exploiting the ideas covered within this disclosure.

Embodiments provide a spectrum sharing solution between LTE and NR that allows a common set of SRS sequences to be assigned to LTE or NR WD's that reduces the number of PRBs that have to be reserved for sounding, instead allowing use of the PRBs to allocate more PUSCH and PUCCH.

Referring now to the drawing figures, in which like elements are referred to by like reference numerals, there is shown in <FIG> a schematic diagram of a communication system <NUM>, according to an embodiment, such as a 3GPP-type cellular network that may support standards such as LTE and/or NR (<NUM>), which comprises an access network <NUM>, such as a radio access network, and a core network <NUM>. The access network <NUM> comprises a plurality of network nodes 16a, 16b, 16c (referred to collectively as network nodes <NUM>), such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 18a, 18b, 18c (referred to collectively as coverage areas <NUM>). Each network node 16a, 16b, 16c is connectable to the core network <NUM> over a wired or wireless connection <NUM>. A first wireless device (WD) 22a located in coverage area 18a is configured to wirelessly connect to, or be paged by, the corresponding network node 16a. A second WD 22b in coverage area 18b is wirelessly connectable to the corresponding network node 16b. While a plurality of WDs 22a, 22b (collectively referred to as wireless devices <NUM>) are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole WD is in the coverage area or where a sole WD is connecting to the corresponding network node <NUM>. Note that although only two WDs <NUM> and three network nodes <NUM> are shown for convenience, the communication system may include many more WDs <NUM> and network nodes <NUM>.

A network node <NUM> is configured to include a node spectrum sharing unit <NUM> which is configured to identify at least one common sounding reference signal (SRS) sequence for at least one Long Term Evolution (LTE) WD and at least one New Radio (NR) WD; and allocate at least one physical resource block (PRB) reserved for the at least one common SRS sequence to at least one of a physical uplink shared channel (PUSCH) and a physical uplink control channel (PUCCH). A wireless device <NUM> is configured to include a WD spectrum sharing unit <NUM> which is configured to use at least one physical resource block (PRB) reserved for at least one sounding reference signal (SRS) sequence for at least one of a physical uplink shared channel (PUSCH) and/or a physical uplink control channel (PUCCH).

The host application <NUM> may be operable to provide a service to a remote user, such as a WD <NUM> connecting via an OTT connection <NUM> terminating at the WD <NUM> and the host computer <NUM>. The "user data" may be data and information described herein as implementing the described functionality. In one embodiment, the host computer <NUM> may be configured for providing control and functionality to a service provider and may be operated by the service provider or on behalf of the service provider. The processing circuitry <NUM> of the host computer <NUM> may enable the host computer <NUM> to observe, monitor, control, transmit to and/or receive from the network node <NUM> and or the wireless device <NUM>. The processing circuitry <NUM> of the host computer <NUM> may include a monitoring unit <NUM> configured to enable the service provider to monitor the network node <NUM> and or the wireless device <NUM>.

In particular, in addition to or instead of a processor, such as a central processing unit, and memory, the processing circuitry <NUM> may comprise integrated circuitry for processing and/or control, e.g., one or more processors and/or processor cores and/or FPGAs (Field Programmable Gate Array) and/or ASICs (Application Specific Integrated Circuits) adapted to execute instructions.

Thus, the network node <NUM> further has software <NUM> stored internally in, for example, memory <NUM>, or stored in external memory (e.g., database, storage array, network storage device, etc.) accessible by the network node <NUM> via an external connection. The processing circuitry <NUM> may be configured to control any of the methods and/or processes described herein and/or to cause such methods, and/or processes to be performed, e.g., by network node <NUM>. Processor <NUM> corresponds to one or more processors <NUM> for performing network node <NUM> functions described herein. The memory <NUM> is configured to store data, programmatic software code and/or other information described herein. In some embodiments, the software <NUM> may include instructions that, when executed by the processor <NUM> and/or processing circuitry <NUM>, causes the processor <NUM> and/or processing circuitry <NUM> to perform the processes described herein with respect to network node <NUM>. For example, processing circuitry <NUM> of the network node <NUM> may include node spectrum sharing unit <NUM> configured to identify at least one common sounding reference signal (SRS) sequence for at least one Long Term Evolution (LTE) WD and at least one New Radio (NR) WD; and allocate at least one physical resource block (PRB) reserved for the at least one common SRS sequence to at least one of a physical uplink shared channel (PUSCH) and a physical uplink control channel (PUCCH).

The processing circuitry <NUM> may be configured to control any of the methods and/or processes described herein and/or to cause such methods, and/or processes to be performed, e.g., by WD <NUM>. The processor <NUM> corresponds to one or more processors <NUM> for performing WD <NUM> functions described herein. The WD <NUM> includes memory <NUM> that is configured to store data, programmatic software code and/or other information described herein. In some embodiments, the software <NUM> and/or the client application <NUM> may include instructions that, when executed by the processor <NUM> and/or processing circuitry <NUM>, causes the processor <NUM> and/or processing circuitry <NUM> to perform the processes described herein with respect to WD <NUM>. For example, the processing circuitry <NUM> of the wireless device <NUM> may include a WD spectrum sharing unit <NUM> configured to use at least one physical resource block (PRB) reserved for at least one sounding reference signal (SRS) sequence for at least one of a physical uplink shared channel (PUSCH) and a physical uplink control channel (PUCCH).

In some embodiments, the host computer <NUM> includes processing circuitry <NUM> and a communication interface <NUM> that is configured to receive user data originating from a transmission from a WD <NUM> to a network node <NUM>.

Although <FIG> and <FIG> show various "units" such as node spectrum sharing unit <NUM>, and WD spectrum sharing unit <NUM> as being within a respective processor, it is contemplated that these units may be implemented such that a portion of the unit is stored in a corresponding memory within the processing circuitry. In other words, the units may be implemented in hardware or in a combination of hardware and software within the processing circuitry.

<FIG> is a flowchart illustrating an exemplary method implemented in a communication system, such as, for example, the communication system of <FIG> and <FIG>, in accordance with one embodiment. The communication system may include a host computer <NUM>, a network node <NUM> and a WD <NUM>, which may be those described with reference to <FIG>. In a first step of the method, the host computer <NUM> provides user data (Block S <NUM>). In an optional substep of the first step, the host computer <NUM> provides the user data by executing a host application, such as, for example, the host application <NUM> (Block S <NUM>). In a second step, the host computer <NUM> initiates a transmission carrying the user data to the WD <NUM> (Block S104). In an optional third step, the network node <NUM> transmits to the WD <NUM> the user data which was carried in the transmission that the host computer <NUM> initiated, in accordance with the teachings of the embodiments described throughout this disclosure (Block S <NUM>). In an optional fourth step, the WD <NUM> executes a client application, such as, for example, the client application <NUM>, associated with the host application <NUM> executed by the host computer <NUM> (Block S108).

<FIG> is a flowchart illustrating an exemplary method implemented in a communication system, such as, for example, the communication system of <FIG>, in accordance with one embodiment. The communication system may include a host computer <NUM>, a network node <NUM> and a WD <NUM>, which may be those described with reference to <FIG> and <FIG>. In a first step of the method, the host computer <NUM> provides user data (Block S110). In an optional substep (not shown) the host computer <NUM> provides the user data by executing a host application, such as, for example, the host application <NUM>. In a second step, the host computer <NUM> initiates a transmission carrying the user data to the WD <NUM> (Block S112). In an optional third step, the WD <NUM> receives the user data carried in the transmission (Block S114).

<FIG> is a flowchart illustrating an exemplary method implemented in a communication system, such as, for example, the communication system of <FIG>, in accordance with one embodiment. The communication system may include a host computer <NUM>, a network node <NUM> and a WD <NUM>, which may be those described with reference to <FIG> and <FIG>. In an optional first step of the method, the WD <NUM> receives input data provided by the host computer <NUM> (Block S116). In an optional substep of the first step, the WD <NUM> executes the client application <NUM>, which provides the user data in reaction to the received input data provided by the host computer <NUM> (Block S118). Additionally or alternatively, in an optional second step, the WD <NUM> provides user data (Block S120). In an optional substep of the second step, the WD provides the user data by executing a client application, such as, for example, client application <NUM> (Block S122). In providing the user data, the executed client application <NUM> may further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the WD <NUM> may initiate, in an optional third substep, transmission of the user data to the host computer <NUM> (Block S124). In a fourth step of the method, the host computer <NUM> receives the user data transmitted from the WD <NUM>, in accordance with the teachings of the embodiments described throughout this disclosure (Block S126).

<FIG> is a flowchart illustrating an exemplary method implemented in a communication system, such as, for example, the communication system of <FIG>, in accordance with one embodiment. The communication system may include a host computer <NUM>, a network node <NUM> and a WD <NUM>, which may be those described with reference to <FIG> and <FIG>. In an optional first step of the method, in accordance with the teachings of the embodiments described throughout this disclosure, the network node <NUM> receives user data from the WD <NUM> (Block S128). In an optional second step, the network node <NUM> initiates transmission of the received user data to the host computer <NUM> (Block S <NUM>). In a third step, the host computer <NUM> receives the user data carried in the transmission initiated by the network node <NUM> (Block S132).

<FIG> is a flowchart of an exemplary process in a network node <NUM> for spectrum sharing between LTE and NR wireless devices <NUM> according to some embodiments of the present disclosure. One or more Blocks and/or functions performed by network node <NUM> may be performed by one or more elements of network node <NUM> such as by node spectrum sharing unit <NUM> in processing circuitry <NUM>, processor <NUM>, communication interface <NUM>, radio interface <NUM>, etc. In one or more embodiments, network node <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM>, radio interface <NUM> and communication interface <NUM> is configured to identify (Block S134) at least one common sounding reference signal (SRS) sequence for at least one Long Term Evolution (LTE) WD <NUM> and at least one New Radio (NR) WD <NUM>. In one or more embodiments, network node <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM>, radio interface <NUM> and communication interface <NUM> is configured to allocate (Block S136) at least four physical resource blocks (PRB) reserved for the at least one common SRS sequence to a physical uplink shared channel (PUSCH) or a physical uplink control channel (PUCCH).

In one or more embodiments, the at least one common SRS sequence further comprises the common Zadoff-Chu root sequences of the SRS for the at least one LTE wireless device <NUM> and at least one NR wireless device <NUM>. In one or more embodiments, network node <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM>, radio interface <NUM> and communication interface <NUM> is configured to employ a single SRS process for uplink (UL) channel estimation of one of the at least one LTE wireless device <NUM> and at least one NR wireless device <NUM> in a shared spectrum of the at least one LTE wireless device <NUM> and at least one NR wireless device <NUM>. In one or more embodiments, network node <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM>, radio interface <NUM> and communication interface <NUM> is configured to use an existing SRS configuration message in a Radio Resource Control (RRC) Connection Setup and an RRC Connection Reconfiguration to signal an SRS configuration.

In one or more embodiments, network node <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM>, radio interface <NUM> and communication interface <NUM> is configured to partition the at least one SRS sequence between the LTE WD <NUM> and the NR WD <NUM> based at least on a relative ratio of the NR BWP to the total bandwidth of the shared spectrum. In one or more embodiments, network node <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM>, radio interface <NUM> and communication interface <NUM> is configured to partition the at least one SRS sequence based at least on part on a distribution of LTE WDs <NUM> and NR WDs <NUM>. In one or more embodiments, network node <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM>, radio interface <NUM> and communication interface <NUM> is configured to re-use the SRS across different beam assignments. <FIG> is a flowchart of an exemplary process in a network node <NUM> according to some embodiments of the present disclosure. One or more Blocks and/or functions performed by network node <NUM> may be performed by one or more elements of network node <NUM> such as by node spectrum sharing unit <NUM> in processing circuitry <NUM>, processor <NUM>, communication interface <NUM>, radio interface <NUM>, etc. In one or more embodiments, network node <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM>, radio interface <NUM> and communication interface <NUM> is configured to assign (Block S <NUM>) a plurality of wireless devices respective sounding reference signal, SRS, sequences of a common set of SRS sequences where the common set of SRS sequences are shared among a first radio access technology, RAT, and a second RAT, as described herein. In one or more embodiments, network node <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM>, radio interface <NUM> and communication interface <NUM> is configured to receive (Block S140) SRS sequences according to the assignment of the respective SRS sequences of the common set of SRS sequences, as described herein.

According to one or more embodiments, the common set of sequences are partitioned equally among first RAT wireless devices <NUM> and second RAT wireless devices <NUM>. According to one or more embodiments, the common set of sequences are partitioned based at least on a fraction of deployments of first RAT wireless devices <NUM> and second RAT wireless devices <NUM>. According to one or more embodiments, the common set of sequences are partitioned based at least on a ratio of bandwidth parts (BWPs) associated with second RAT wireless devices <NUM> to a total bandwidth of shared spectrum. According to one or more embodiments, the processing circuitry <NUM> is further configured to: determine a first region in a first RAT cell fails to overlap with second region in a second RAT cell; and configure the first region in the first RAT cell and the second region in the second RAT cell to reuse SRS sequences.

According to one or more embodiments, the common set of SRS sequences are configured for a time division duplex, TDD, same numerology non-standalone spectrum sharing between the first RAT and second RAT. According to one or more embodiments, the assignment of the respective SRS sequences of the common set of SRS sequences is indicated using radio resource control, RRC, signaling. According to one or more embodiments, a first set of SRS sequences of the common set of SRS sequences are assigned to a first set of first RAT beams and a second set of SRS sequence of the common set of SRS sequence are assigned to a second set of second RAT beams.

<FIG> is a flowchart of an exemplary process in a wireless device <NUM> for spectrum sharing between LTE and NR wireless devices <NUM> according to some embodiments of the present disclosure. One or more Blocks and/or functions performed by wireless device <NUM> may be performed by one or more elements of wireless device <NUM> such as by WD spectrum sharing unit <NUM> in processing circuitry <NUM>, processor <NUM>, radio interface <NUM>, etc. In one or more embodiments, wireless device <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM> and radio interface <NUM> is configured to use (Block S142) at least four physical resource blocks (PRB) reserved for at least one sounding reference signal (SRS) sequence for a physical uplink shared channel (PUSCH) or a physical uplink control channel (PUCCH).

In one or more embodiments, the at least one SRS sequence further comprises the common Zadoff-Chu root sequences of the SRS for at least one Long Term Evolution (LTE) WD <NUM> and at least one New Radio (NR) wireless device <NUM>.

In one or more embodiments, wireless device <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM> and radio interface <NUM> is configured to receive an SRS configuration in an existing SRS configuration message in at least one of a Radio Resource Control (RRC) Connection Setup and an RRC Connection Reconfiguration.

<FIG> is a flowchart of an exemplary process in a wireless device <NUM> according to some embodiments of the present disclosure. One or more Blocks and/or functions performed by wireless device <NUM> may be performed by one or more elements of wireless device <NUM> such as by WD spectrum sharing unit <NUM> in processing circuitry <NUM>, processor <NUM>, radio interface <NUM>, etc. In one or more embodiments, wireless device <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM> and radio interface <NUM> is configured to receive (Block S <NUM>) an assignment of a first sounding reference signal, SRS, sequence of a common set of SRS sequences where the common set of SRS sequences are shared among a first radio access technology, RAT, and a second RAT, as described herein. In one or more embodiments, wireless device <NUM> such as via one or more of processing circuitry <NUM>, processor <NUM> and radio interface <NUM> is configured to transmit (Block S <NUM>) the first SRS sequence according to the assignment, as described herein.

According to one or more embodiments, the common set of sequences are partitioned equally among first RAT wireless devices and second RAT wireless devices <NUM>. According to one or more embodiments, the common set of sequences are partitioned based at least on a fraction of deployments of first RAT wireless devices <NUM> and second RAT wireless devices <NUM>. According to one or more embodiments, the common set of sequences are partitioned based at least on a ratio of bandwidth parts (BWPs) associated with second RAT wireless devices <NUM> to a total bandwidth of shared spectrum.

According to one or more embodiments, the common set of SRS sequences are configured for a time division duplex, TDD, same numerology non-standalone spectrum sharing between the first RAT and second RAT. According to one or more embodiments, the assignment is indicated using radio resource control, RRC, signaling. According to one or more embodiments, a first set of SRS sequences of the common set of SRS sequences are assigned to a first set of first RAT beams and a second set of SRS sequence of the common set of SRS sequence are assigned to a second set of second RAT beams.

Having described the general process flow of arrangements of the disclosure and having provided examples of hardware and software arrangements for implementing the processes and functions of the disclosure, the sections below provide details and examples of arrangements for supporting a spectrum sharing solution between LTE and NR, that allows a common set of SRS sequences to be assigned to LTE or NR WD's <NUM> that reduce the number of PRBs that have to be reserved for sounding and may instead use them to allocate more PUSCH and PUCCH.

It is noted that references are made below to one or more of WD <NUM> and/or network node <NUM> performing certain functions. Functions performed by a network node <NUM> can be performed by one or more of the elements shown as comprised in network node <NUM>, such as, but not limited to processing circuitry <NUM>, node spectrum sharing unit <NUM>, communication interface <NUM> and/or radio interface <NUM>. Functions performed by a WD <NUM> can be performed by one or more of the elements shown as comprised in WD <NUM>, such as, but not limited to processing circuitry <NUM>, WD spectrum sharing unit <NUM>, and/or radio interface <NUM>.

One embodiment provides a Frequency Division Duplexing (FDD)/ Time Division Duplexing (TDD) same numerology Non-Standalone (NSA) spectrum sharing arrangement between NR and LTE SRS functionality on a single carrier of total bandwidth (BW) in which the common Zadoff-Chu root sequences of the SRS for the NR and LTE WDs <NUM> may be assigned to an NR WD <NUM> or LTE WD <NUM>. As explained above, in some embodiments, <NUM> LTE configurations are typically common between the LTE and NR RATs. From the perspective of the network, e.g., the network node <NUM>, it may not matter whether the UL SRS was sent by the LTE WD <NUM> or NR WD <NUM> if the transmitted sequence is the same. However, these common sequences can be re-used or partitioned between the LTE and NR WDs <NUM>.

The partitioning may be implemented such as via one or more of processing circuitry <NUM>, node spectrum sharing unit <NUM>, etc., using one of the following example methods; equally between NR and LTE; or between NR and LTE based on the fraction of WDs <NUM> for each of the NR and LTE deployments.

For NR WD's <NUM> assigned a Bandwidth Part (BWP) in the shared spectrum, the SRS sequences can be partitioned such as via one or more of processing circuitry <NUM>, node spectrum sharing unit <NUM>, etc., between LTE and NR WD's <NUM> based on the relative ratio of the NR BWP to the total bandwidth of the shared spectrum.

Due to the commonality of SRS sequences between LTE and NR, the existing SRS configuration message in the RRC Connection Setup and RRC Connection Reconfiguration may be employed to signal the SRS configuration, e.g., through use of the srs-ConfigIndex and transmissionComb fields of the RRC message. Table <NUM> (referenced from 3GPP Technical Specification (TS) <NUM> Table <NUM>. <NUM>-<NUM>) highlights the NR SRS configurations that are similar with SRS LTE shown in bold and italicized in Table <NUM>.

Some embodiments may include an extension of the above discussed embodiments for use of the SRS in a spectrum sharing scenario employing a mixed NR stand-alone (SA) plus LTE scenario. For these embodiments, the same method as defined above may be employed for scenarios in which there is a one-to-one correspondence between the LTE and NR cells employing spectrums sharing. In scenarios for which the NR and LTE cells have regions that are not overlapping, no sharing of SRS sequences is required.

One embodiment provides an extension of the above discussed embodiments for use of SRS in an NSA TDD same numerology spectrum sharing scenario. The methods defined in the above discussion can also apply to TDD implementations of LTE and NR. One embodiment makes use of NR SRS beam assignments and M-port SRS with spatial filtering to a number (N) of antennas through the SRS resource indicator (SRI). Embodiments may re-use the NR SRS and LTE SRS across different beam assignments.

<FIG> is an illustration of an example sounding reference signal frequency assignment for spectrum sharing that may be implemented by network node <NUM> such as via one or more of processing circuitry <NUM>, node spectrum sharing unit <NUM>, etc., according to some embodiments of the present disclosure as set forth below. <FIG> is an illustration of another example sounding reference signal frequency assignment for spectrum sharing that may be implemented by network node <NUM> such as via one or more of processing circuitry <NUM>, node spectrum sharing unit <NUM>, etc., according to some embodiments of the present disclosure as set forth below.

<FIG> is an illustration of example parameters defining sounding reference signal resources within a slot according to some embodiments of the present disclosure.

<FIG> is an example of parameters of SRS resource allocation in the time domain according to some embodiments of the present disclosure. <FIG> is another example of parameters of SRS resource allocation in the time domain according to some embodiments of the present disclosure. <FIG> is still another example of parameters of SRS resource allocation in the time domain according to some embodiments of the present disclosure. <FIG> is yet another example of parameters of SRS resource allocation in the time domain according to some embodiments of the present disclosure.

<FIG> is an example of a comb <NUM> configuration in the frequency domain according to some embodiments of the present disclosure. <FIG> is another example of a comb <NUM> configuration in the frequency domain according to some embodiments of the present disclosure. <FIG> is another example of a comb <NUM> configuration in the frequency domain according to some embodiments of the present disclosure.

Different hatching patterns correspond to different SRS signal numbers in <FIG>.

Since SRS resources are positioned in a certain interval in the frequency domain similar to the manner shown with respect to the time domain in <FIG>, multiple SRS may be interleaved (multiplexed) along the frequency domain occupying the same OFDM symbols as shown in <FIG> and <FIG>.

For a comb <NUM> configuration, two SRS signals may be multiplexed as shown in <FIG>. For a comb <NUM> configuration, a maximum of <NUM> SRS signals may be multiplexed as shown in <FIG>.

<FIG> is an illustration of an example sounding reference signal bandwidth configuration definition according to some embodiments of the present disclosure.

Some factors defining the location and bandwidth of SRS may be defined for example by 3GPP TS <NUM>-Table <NUM>. <NUM>-<NUM>. Some of the Radio Resource Control (RRC) parameters determine which row of the table is used for a specific SRS Resource set as illustrated in <FIG>.

Claim 1:
A network node (<NUM>), comprising:
processing circuitry (<NUM>) configured to:
assign a plurality of wireless devices (<NUM>) respective sounding reference signal, SRS, sequences of a common set of SRS sequences, the common set of SRS sequences being shared among a first radio access technology, RAT, and a second RAT; and
receive SRS sequences according to the assignment of the respective SRS sequences of the common set of SRS sequences;
wherein the common set of sequences are partitioned:
equally among first RAT wireless devices (<NUM>) and second RAT wireless devices (<NUM>), or
based at least on a fraction of deployments of first RAT wireless devices (<NUM>) and second RAT wireless devices (<NUM>), or
based at least on a ratio of bandwidth parts , BWPs, associated with second RAT wireless devices (<NUM>) to a total bandwidth of shared spectrum.