Demodulation reference signal for shared radio

Abstract

A method and apparatus are provided for demodulation reference signal configuration in a shared radio spectrum system. The method is performed by a wireless device (110, 200). The wireless device (200) is configured to operate in a communication system, the communication system comprising a radio spectrum shared by multiple radio access technologies. The method includes obtaining (600) a configuration for a demodulation reference signal, the DMRS including a pattern using common resource elements of at least two of the multiple radio access technologies, and transmitting or receiving (630) data based on the obtained demodulation reference signal. The method is performed by a network node (160). The method includes the network node determining (700) a configuration for the demodulation reference signal, the DMRS having a pattern using common resource elements of at least two of the multiple radio access technologies, and receiving or transmitting (720) a data transmission based on the determined configuration for the demodulation reference signal.

Description

[Technical field]

[0001] The present disclosure relates to demodulation reference signals (DMRS), and in particular to their configuration, in systems having a radio spectrum shared by different radio access technologies. [Background technology]

[0002] In mobile radio systems such as LTE and NR, a reference signal (RS) is usually transmitted to aid in radio channel knowledge, but can also be transmitted to track impairments induced by the transceiver's local oscillator. The design of the reference signal depends on its use case, and in mobile radio systems, multiple types of reference signals are needed. The primary purpose of a reference signal is often reflected by its name.

[0003] For example, a reference signal designed and used for coherent demodulation of a physical layer channel is called DM-RS, a reference signal designed and used for obtaining channel state information in the downlink is called CSI-RS, and a reference signal designed for tracking time and frequency differences between a transmitter and a receiver is called TRS.

[0004] On the other hand, LTE specified a cell-specific reference signal (CRS) with multiple purposes including mobility and new cell detection. Therefore, CRS can never be disabled and must always be transmitted by LTE cells even if there are no users served. LTE may also use DM-RS based demodulation of data when configured in any of the transmission modes 7 to 10. Here, transmission modes (TM) 9 and TM10 are the most interesting because these DM-RS patterns support up to 8 ports and allow high spectral efficiency transmission and a high degree of multi-user MIMO, i.e. many simultaneously scheduled (co-scheduled) users on the same time and frequency resources using orthogonal DM-RS.

[0005] According to the 3GPP agreement, due to the wide range of use cases envisioned for NR, as well as other factors, each of the above reference signals is highly configurable: they may occupy many different OFDM symbols within a slot of a radio frame, and may occupy different sets of subcarriers within each OFDM symbol.

[0006] NR DMRS can be configured with 1, 2, 3 or 4 DMRS symbols in a slot (a slot has 14 OFDM symbols). A physical downlink shared channel (PDSCH) can be scheduled with less than 14 symbols, in which case the DMRS are moved closer together and eventually dropped if the PDSCH duration is too short to accommodate the configured number of DMRS symbols. A schematic of NR DMRS location in Release 15 can be seen in Figure 1, which shows the possible NR DMRS symbol locations within a 14-symbol slot. Both single-symbol DMRS and double-symbol DMRS are supported, where there are two means by which DMRS symbols are paired using adjacent symbols.

[0007] As shown in Figure 1, as an example, if the PDSCH duration is 11 symbols and two additional DMRS symbols are configured, they are placed at symbol index 6 and 9, with symbol index numbers ranging from 0 to 13. The location of the first symbol containing the DMRS is within symbols with index 2 or 3, as specified by the cell-specific system information provided by the Master Information Block (MIB).

[0008] When a single slot and a single resource block (RB) are observed, assuming a single DMRS OFDM symbol, the NR DM-RS is as shown in FIG. 2.

[0009] In LTE, when two CRS ports are configured (denoted as CRS ports 0 and 1 in LTE), the CRS locations in the DL subframe are dense and occupy resource element symbols with slot indices 0, 4, 7 and 11. When four CRS ports are configured, the CRS occupies symbols with slot indices 0, 1, 4, 7, 8 and 11. However, when four ports are configured, the third and fourth ports (CRS ports 2 and 3) are only used when receiving PDSCH and are not used for mobility measurements, since these measurements are defined only for LTE ports 0 and 1. An example of a CRS location in LTE is shown in Figure 3.

[0010] For LTE transmission modes 9 and 10, which are the most useful for MU-MIMO, the DM-RS pattern for a physical RB (PRB) pair is shown in Figure 4.

[0011] It is possible for NR and LTE carriers to operate in the same frequency band, known as NR and LTE coexistence. This is also called dynamic spectrum sharing (DSS). A terminal connected to an LTE carrier is unaware that there is a potential NR transmission when there is no ongoing LTE transmission. On the other hand, a terminal connected to an NR carrier can be configured to be aware of a potential overlap with an LTE carrier. CRS for LTE cannot be disabled, so slots do not go empty even if there is no LTE traffic.

[0012] Therefore, if LTE and NR use the same subcarrier spacing, i.e., 15 kHz, NR will provide signaling of the CRS location to NR UEs using at least the RRC parameters lte-CRS-ToMatchAround for the CRS location and nrofCRS-Ports for the number of CRS ports (1, 2 or 4).

[0013] This allows for coexistence of LTE and NR on the same carrier where the NR PDSCH can be mapped around the LTE CRS.

[0014] It is observed that the NR DM-RS in symbol l1=11 collides with the LTE CRS in symbol 11 for PDSCH durations of 13 and 14, and therefore there is a specified rule in NR Release 15 that says that if lte-CRS-ToMatchAround is configured in the NR UE, then l1=12 is used instead of l1=11 for these PDSCH durations. In this way, the NR DM-RS does not collide with the LTE CRS and coexistence is achieved.

[0015] For MU-MIMO scheduling, there are two possibilities from the network:

[0016] 1. Transparent MU-MIMO, where the transmission to user A is independent of the transmission to user B. User A is unaware of the ongoing MU-MIMO transmission to user B and vice versa. The DM-RS of user A may be interfered with by the PDSCH and / or DM-RS transmitted to user B and vice versa.

[0017] 2. Non-transparent MU-MIMO, where user A is aware of the simultaneous transmissions to user B and vice versa, and also knows the antenna ports (i.e., DMRS) used for the other users. This allows the UE to coherently estimate the channel of the interfering transmissions by using the DM-RS. This further allows for improved interference suppression and better performance compared to transparent MU-MIMO. Summary of the Invention

[0018] In a first aspect, a method is provided that is performed by a wireless device operating in a communication system. The communication system includes use of a wireless spectrum shared by a plurality of radio access technologies. The method includes obtaining a configuration for a demodulation reference signal (DMRS), the DMRS occupying resource elements identified by a pattern and using common resource elements of at least two of the plurality of radio access technologies. For example, the DMRS may be configured for a first radio access technology and occupy the same resource elements as a DMRS configured for a second radio access technology. The method also includes transmitting or receiving a data transmission based on the obtained demodulation reference signal. In some examples of this aspect, the DMRS is configured for the first radio access technology and is orthogonal or quasi-orthogonal to a DMRS configured for a different one of the plurality of radio access technologies. The different one of the plurality of radio access technologies may further be configured with a cell-specific reference signal (CRS). The DMRS may additionally or alternatively include a sequence having at least partially co-scheduled radio resource elements for another one of the multiple radio access technologies, derived by code domain multiplexing (CDM), and using the same DMRS sequence as the DMRS for another user. In some examples, the DMRS comprises a time-domain orthogonal cover code (OCC) of length 4 for a group of four resource elements, or of length 2 for a group of two resource elements. In further examples, a length 2 OCC is applied to one of the CDM groups, each CDM group corresponding to two unique antenna ports, or a length 4 OCC is applied to one of the CDM groups, each CDM group corresponding to four unique antenna ports. In some examples of this aspect, the method further includes obtaining an antenna port indication. Further, the antenna port indication may include indicating whether other ports in the same CDM group are scheduled. Additionally or alternatively, the indication may include the number of CDM groups for which physical downlink shared channel data is not scheduled.In other examples of this aspect, the CDM may correspond to an OCC of length 4 depending on the subcarrier and / or physical resource block index. In other examples of this aspect, the obtained DMRS configuration may be a first DMRS configuration, and the method further includes obtaining a second DMRS configuration, the second DMRS configured for resource elements that are unique from a cell-specific reference signal configured for any one of the DMRS and the other radio access technology. Further, the method may include receiving an indication to select between the first DMRS configuration and the second DMRS configuration. In some examples of this aspect, the DMRS configuration may be for uplink multi-user multiple-input multiple-output (MU-MIMO).

[0019] In a second aspect, a method is provided that is performed by a network node in a communication system. The communication system includes use of a radio spectrum shared by a plurality of radio access technologies. The method includes determining a configuration for a demodulation reference signal DMRS, where the DMRS occupies resource elements identified by a pattern and uses common resource elements of at least two of the plurality of radio access technologies. For example, the DMRS may be configured for a first radio access technology and occupies the same resource elements as a DMRS configured for a second radio access technology. The method includes receiving or transmitting a data transmission based on the determined configuration for the demodulation reference signal. In some examples of this aspect, the method includes configuring a wireless device with the determined configuration for the DMRS. In some examples, the DMRS is configured for a first radio access technology and is orthogonal or quasi-orthogonal to a DMRS configured for a different one of the plurality of radio access technologies. Additionally, the different one of the plurality of radio access technologies may be configured with a cell-specific reference signal (CRS). In some examples of this aspect, the DMRS comprises a sequence derived by code domain multiplexing (CDM) and with co-scheduled radio resource elements for another one of the multiple radio access technologies using the same DMRS sequence as the DMRS for the other user. Further, the DMRS may comprise a time domain orthogonal cover code OCC of length 4 for a group of four resource elements or of length 2 for a group of two resource elements. Further, in some examples, a length 2 OCC is applied to one of the CDM groups, each CDM group corresponding to two unique antenna ports, and a length 4 OCC is applied to one of the CDM groups, each CDM group corresponding to four unique antenna ports. In some examples of this aspect, the method further comprises transmitting an antenna port indication to the wireless device. Further, the antenna port indication may comprise indicating whether other ports in the same CDM group are scheduled.Additionally or alternatively, the indication includes a number of CDM groups for which physical downlink shared channel data is not scheduled. In some examples of this aspect, the CDM corresponds to an OCC of length 4, depending on the subcarrier and / or physical resource block index. In some examples of this aspect, the determined DMRS configuration is a first DMRS configuration, and the method further includes determining a second DMRS configuration, the second DMRS configured for resource elements that are unique from the DMRS and cell-specific reference signals configured for any one of the other radio access technologies. Furthermore, in some examples, the method includes transmitting an indication to the wireless device to select between the first DMRS configuration and the second DMRS configuration. In some examples of this aspect, the DMRS configuration is for uplink multi-user multiple-input multiple-input multiple-output (MU-MIMO).

[0020] In another aspect, a wireless device is provided. The wireless device includes a processing circuit, a transmission / reception (transceiver) circuit, a memory, and a power supply circuit configured to power the wireless device. The processing circuit is configured to obtain a configuration for a demodulation reference signal (DMRS), where the DMRS includes a pattern using common resource elements of at least two of a plurality of radio access technologies. The processing circuit is also configured to receive or transmit a data transmission based on the obtained demodulation reference signal. In some examples, the processing circuit is further configured to perform any one of the methods of the first aspect.

[0021] In another aspect, a network node is provided. The network node includes a processing circuit configured to provide power to the network node, a transceiver circuit, and a power supply circuit. The processing circuit is configured to determine a configuration for a demodulation reference signal (DMRS), where the DMRS includes a pattern of using common resource elements of at least two of a plurality of radio access technologies. The processing circuit is also configured to receive or transmit a data transmission based on the determined demodulation reference signal. In some examples, the processing circuit is further configured to perform any one of the methods of the second aspect.

[0022] In another aspect, there is provided a computer program comprising instructions which, when executed on a computer or processing circuit, cause the computer or processing circuit to perform any one of the methods of the first or second aspects.

[0023] In another aspect, a computer program product, memory, or carrier comprising computer program instructions according to the computer program described above. [Brief description of the drawings]

[0024] A more complete understanding of the embodiments of the present invention, together with its attendant advantages and features, will be more readily understood by reference to the following detailed description in conjunction with the accompanying drawings, in which: [Figure 1] FIG. 1 shows an example of a DMRS configuration. [Diagram 2] FIG. 2 shows an example of a DMRS and antenna port configuration. [Diagram 3] FIG. 3 shows an example of a CRS location in LTE. [Figure 4] FIG. 4 shows a further example of a DMRS and antenna port configuration. [Diagram 5] FIG. 5 shows an example of a DMRS and CRS configuration with LTE and NR coexistence. [Figure 6] FIG. 6 illustrates an example of a DMRS configuration according to an embodiment of the present disclosure. [Figure 7] FIG. 7 illustrates a further example of a DMRS configuration according to an embodiment of the present disclosure. [Figure 8] FIG. 8 illustrates an example of resource scheduling according to some embodiments of the disclosure. [Figure 9] FIG. 9 is a flow chart according to some embodiments of the present disclosure. [Figure 10] FIG. 10 is a flow chart according to some embodiments of the present disclosure. [Figure 11] FIG. 11 illustrates an example of a communication system according to some embodiments. [Figure 12] FIG. 12 illustrates an example of a user device according to some embodiments. [Figure 13] FIG. 13 illustrates an example of a virtualization environment according to some embodiments. [Figure 14] FIG. 14 illustrates an example of a telecommunications network connected to a host computer through an intermediate network, according to some embodiments. [Figure 15] FIG. 15 illustrates an example of a host computer communicating with user equipment via a base station over a partial wireless connection according to some embodiments. [Figure 16] FIG. 16 illustrates an example of a method implemented in a communications system including a host computer, a base station, and a user equipment, according to some embodiments. [Figure 17] FIG. 17 illustrates an example of a method implemented in a communications system including a host computer, a base station, and a user equipment, according to some embodiments. [Figure 18] FIG. 18 illustrates an example of a method implemented in a communications system including a host computer, a base station, and a user equipment, according to some embodiments. [Figure 19] FIG. 19 illustrates an example of a method implemented in a communications system including a host computer, a base station, and a user equipment, according to some embodiments. [Figure 20] FIG. 20 illustrates a UE device according to some embodiments. [Figure 21] FIG. 21 illustrates a UE device according to some embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] In general, all terms used herein should be interpreted according to their ordinary meaning in the relevant technical field unless a different meaning is expressly given and / or implied from the context in which it is used. All references to elements, apparatus, components, means, steps, etc. should be openly interpreted as referring to at least one instance of the element, apparatus, component, means, step, etc., unless otherwise specified. The steps of any method disclosed herein need not be performed in the exact order disclosed, unless a step is explicitly described as following or preceding another step, and / or if it is implicit that a step must follow or precede another step. Any feature of any of the embodiments disclosed herein may be applied to any other embodiment, where appropriate. Similarly, any advantage of any embodiment may be applied to any other embodiment, and vice versa. Other objects, features, and advantages of the accompanying embodiments will become apparent from the following description.

[0026] Since the LTE DM-RS pattern collides with the NR DM-RS pattern at symbol l1=12, the question is how to implement MU-MIMO scheduling between an LTE UE and an NR UE using TM9 or 10 when the LTE CRS pattern is configured in the NR UE.

[0027] One solution is to schedule a shorter length NR PDSCH, in which case the NR DM-RS appears in symbol 9, but NR cannot utilize the entire slot, resulting in reduced spectral efficiency for NR, which is problematic. See Figure 5 for a schematic of RS location within a slot relative to NR and LTE reference signals.

[0028] Another issue is the interference to the LTE DM-RS by the NR PDSCH transmission and the interference in the NR DM-RS from the LTE PDSCH transmission. Furthermore, the benefits of non-transparent MU-MIMO cannot be achieved because the NR UE is not aware of the location of the co-scheduled (MU-MIMO scheduled) LTE DM-RS.

[0029] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings, in which: However, other embodiments are within the scope of the subject matter disclosed herein, and the disclosed subject matter should not be construed as being limited to only the embodiments described herein, but rather, these embodiments are provided as examples to convey the scope of the subject matter to those skilled in the art.

[0030] As used herein, a network node refers to a configured, arranged, and / or operable device that can directly or indirectly communicate with wireless devices and / or communicate with other network nodes or devices in a wireless network to enable and / or provide wireless access to wireless devices and / or perform other functions (e.g., management) in a wireless network. For example, a network node may be a satellite gateway or a satellite-based base station, e.g., a gNB. Other examples of network nodes include, but are not limited to, access points (APs) (e.g., wireless access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR Node Bs (gNBs)). Base stations may be classified based on the amount of coverage they provide (or, in other words, their transmit power levels), and may then be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node that controls a relay. A network node may also include one or more (or all) parts of a distributed radio base station, such as a centralized digital unit and / or a remote radio unit (RRU) (sometimes referred to as a remote radio head (RRH)). Such a remote radio unit may or may not be integrated with an antenna as an antenna-integrated radio. Some of the distributed radio base stations may also be referred to as nodes in a distributed antenna system (DAS). Further examples of network nodes include multi-standard radio (MSR) equipment such as an MSR BS, a network controller such as a radio network controller (RNC) or a base station controller (BSC), a base transceiver station (BTS), a transmission point, a transmission node, a multi-cell / multicast coordination entity (MCE), a core network node (e.g., MSC, MME), an O&M node, an OSS node, a SON node, a positioning node (e.g., E-SMLC), and / or an MDT. As another example, the network node may be a virtual network node, as described in more detail below.More generally, however, a network node may represent any suitable device (or group of devices) capable, configured, arranged, and / or operable to enable and / or provide wireless devices with access to a wireless network or to provide some service to wireless devices that have accessed the wireless network.

[0031] As used herein, a wireless device refers to a device capable of, configured, arranged, and / or operable to wirelessly communicate with network nodes and / or other wireless devices. Unless otherwise noted, the term wireless device may be used interchangeably herein with user equipment (UE). Wireless communication may involve transmitting and / or receiving wireless signals using electromagnetic waves, radio waves, infrared, and / or other types of signals suitable for conveying information over the air. In some embodiments, a wireless device may be configured to transmit and / or receive information without direct human interaction. For example, a wireless device may be designed to transmit information to a network on a predetermined schedule, when triggered by an internal or external event, or in response to a request from the network. Examples of wireless devices include, but are not limited to, smartphones, mobile phones, cellular phones, voice over IP (VoIP) phones, wireless local loop phones, desktop computers, personal digital assistants (PDAs), wireless cameras, game consoles or devices, music storage devices, playback devices, wearable terminal devices, wireless endpoints, mobile stations, tablets, laptops, laptop embedded equipment (LEE), laptop mounted equipment (LME), smart devices, wireless customer premises equipment (CPE), vehicle mounted wireless terminal devices, etc. Wireless devices may support device-to-device (D2D) communications, for example, by implementing 3GPP standards for sidelink communications, vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-everything (V2X), and in this case may be referred to as D2D communications devices. As yet another specific example, in an Internet of Things (IoT) scenario, a wireless device may represent a machine or other device that performs monitoring and / or measurements and transmits results of such monitoring and / or measurements to another wireless device and / or network node. In this case, the wireless device may be a machine-to-machine (M2M) device, which in the 3GPP context may be referred to as an MTC device.As one particular example, the wireless device may be a UE implementing the 3GPP® Narrowband Internet of Things (NB-IoT) standard. Particular examples of such machines or devices are metering devices such as sensors, power meters, industrial machines, or home or personal appliances (e.g., refrigerators, televisions, etc.), personal wearables (e.g., watches, fitness trackers, etc.). In other scenarios, the wireless device may represent a vehicle or other equipment that may monitor and / or report its operating status or other functions related to its operation. The wireless device described above may represent an endpoint of a wireless connection, in which case the device may be referred to as a wireless terminal. Furthermore, the wireless device described above may be mobile, in which case it may be referred to as a mobile device or mobile terminal.

[0032] This application describes embodiments that address at least some of the previously disclosed problems arising from coexisting scheduling between different radio access technologies and using multi-user MIMO. Two exemplary radio access technologies (RATs) for which coexistence is desired are 3GPP® Long Term Evolution (LTE) and 3GPP® New Radio (NR), although the concepts described herein and proposed embodiments are not limited to such RAT types. For example, in the case of NR, a new DM-RS type can be configured to the UE from the network that uses the same resource elements for the DM-RS in a PRB as the LTE DM-RS.

[0033] With the proposed solution, the following MU-MIMO (i.e. co-scheduling two or more UEs on overlapping time / frequency resources) operations are supported: 1. MU-MIMO between one or more LTE UEs and one or more NR UEs configured with the new DM-RS type Here, the NR DM-RS may be configured such that the NR and LTE DM-RS antenna ports used in MU-MIMO scheduling are orthogonal or quasi-orthogonal. b. where the NR bandwidth portion for the NR UE may be larger than the LTE system bandwidth 2. MU-MIMO between an NR UE that does not support the new DM-RS type and an NR UE that has configured the new DM-RS type to enable MU-MIMO with an LTE UE.

[0034] Some advantages are that interference to LTE DM-RS from NR PDSCH is cancelled, interference to NR DM-RS from LTE PDSCH is cancelled, NR UEs can get the benefits of non-transparent MU-MIMO because NR UEs can estimate the channel used for interfering transmissions to LTE UEs, and NR overhead is reduced.

[0035] DM-RS for PDSCH, i.e., for transmission from the gNB to the UE In some embodiments, the network may configure NR UEs with a new DM-RS pattern (referred to herein as DMRS type 3) that is not available to previous NR release (e.g., Rel-15) UEs. This new NR DM-RS type applies to NR UEs configured with OFDM with 15 kHz subcarrier spacing and regular cyclic prefix. Note that LTE only supports 15 kHz subcarrier spacing.

[0036] The new NR DM-RS pattern uses the same resource elements as the TM10 pattern of the LTE DM-RS.

[0037] In some embodiments, the newly defined DM-RS is assigned to NR UEs that is orthogonal or quasi-orthogonal to the LTE DM-RS. The orthogonality to the LTE DM-RS is obtained via code domain multiplexing (CDM) in terms of applying a time domain orthogonal cover code (OCC) of length 4 to groups of four resource elements or length 2 to groups of two resource elements.

[0038] A prerequisite for using CDM is that the new NR DM-RS uses the same sequence, i.e., r(m), used for the LTE DM-RS on the co-scheduled resource elements. The co-scheduled resources may also be described as shared radio spectrum or DSS. In some instances the co-scheduled resource elements overlap, but not necessarily the same set of resources, i.e., the bandwidth scheduled for one co-scheduled radio access technology may differ from the other radio access technology. Instead, in the case of quasi-orthogonality between LTE and NR DM-RS antenna ports, it may be sufficient that the NR DM-RS sequence and the LTE DM-RS sequence have low cross-correlation.

[0039] Two CDM groups (λ=0, 1) are defined with an OCC of length 4 applied per CDM group. This means that the new DM-RS pattern supports up to eight orthogonal DM-RS antenna ports, i.e., four ports per CDM group. The new NR DM-RS mapping to resource elements is shown in Figure 6, where the eight ports are numbered 1000 to 1007. The port numbers for the LTE DM-RS are also shown.

[0040] An example of DM-RS type 3 mapping would be where NR operates in the same bandwidth as LTE, TIFF0007621353000001.tif1120 has the same center frequency as LTE and uses the same DM-RS sequence r(m) as the DM-RS in LTE. Then, the mapping of DM-RS type 3 to resource elements of antenna port p is as follows: TIFF0007621353000002.tif16109 here TIFF0007621353000003.tif4198, where n PRB is the PRB index, TIFF0007621353000004.tif1115, Δ p is defined as: [Table 1]

[0041] Note that LTE has an unused DC subcarrier in the center of its spectrum, but NR does not. For example, a 20 MHz LTE carrier uses 1201 subcarriers (100RBx12 subcarriers / RB+1DC subcarrier), while a 100 RB NR carrier uses only 1200 subcarriers. This means that LTE and NR RBs can be aligned to one side of the LTE DC subcarrier, but not to the other side, see Figure 8. Therefore, the DM-RS patterns in the NR RBs below and above the LTE DC subcarrier must be different (shifted by one subcarrier). This would allow alignment between DM-RS between LTE and NR on both sides of the DC subcarrier.

[0042] Using the same sequence family between DM-RS in LTE and DM-RS in NR type 3 provides additional advantages. To enable this, the following is required: The same DM-RS sequence means that the same scrambling sequence initialization function and generator are used for the new NR DM-RS as in LTE, i.e., the reference signal sequence r(m) is generated the same as in 3GPP TS 36.211 V15.7.0: TIFF0007621353000006.tif11126Gold-31 A pseudorandom sequence c(i) is initialized, TIFF0007621353000007.tif17105Here, the parameter ns is the LTE slot counter. For 15 kHz subcarrier spacing, an NR slot is equal to the length of two LTE slots, so the NR slot counter An equivalent initialization using TIFF0007621353000008.tif1210 can be expressed as: TIFF0007621353000009.tif14100

[0043] Additionally, a new DMRS scrambling seed (N_ID) is introduced, such as the initial value used to calculate the scrambling sequence, using 10 bits, specific to DMRS Type 3 to align with the DM-RS scrambling seed used in LTE so that the exact same sequence can be generated for NR DM-RS used for LTE DM-RS.

[0044] NR supports a scheduling bandwidth larger than the 20 MHz system bandwidth of LTE, so 12 It is necessary to support NR DM-RS type 3 sequences of length greater than TIFF0007621353000010.tif1120, but the segments of the sequences are identical to LTE DM-RS sequences.

[0045] In one embodiment, a new reference point for subcarrier k used for NR DM-RS sequence generation is introduced to estimate the interference channel (non-transparent MU-MIMO) and to align the LTE and NR DM-RS sequences to ensure that an NR UE can use the LTE DM-RS used for transmission to a co-scheduled LTE UE or an NR UE using Type 3 DM-RS.

[0046] Such a reference point is the Type 3 sequence of the NR DM-RS. An example of the introduction into TIFF0007621353000011.tif1217 is shown by the following sequence: TIFF0007621353000012.tif9122, where TIFF0007621353000013.tif1341. The value of m0 is the LTE PRB index n PRB =0.

[0047] Because MU-MIMO in LTE is supported for DM-RS antenna ports associated with CDM group 0 only, and PDSCH is mapped to resource elements associated with CDM group 1, MU-MIMO between NR and LTE UEs is limited to sharing four orthogonal DM-RS ports in a coordinated manner. For example, if antenna port 1000 is used to schedule one NR UE, then antenna ports 8, 11, and 13 can be used to schedule LTE UEs, if antenna ports 1000 and 1001 are used to schedule NR UEs, then antenna ports 11 and 13 can be used to schedule LTE UEs, and so on.

[0048] In one embodiment, an antenna port indication is created for NR DM-RS type 3 to enable NR UEs to schedule a single layer or two layers using antenna ports 1000 and 1001 together by indicating whether other ports in CDM group 0 are being used and whether the number of CDM groups for non-PDSCH DM-RS is equal to 1 or 2.

[0049] In another embodiment, antenna port indication is created for NR DM-RS type 3, allowing single layer scheduling to NR UEs using any of the eight antenna ports 1000-1007. Similarly, antenna port indication allows two layers to be scheduled to NR UEs using any of the antenna port pairs {1000,1001}, {1004,1005}, {1002,1003}, {1006,1007}. This therefore allows more MU-MIMO capacity when only NR UEs are spatially multiplexed.

[0050] The antenna port indication for ports from CDM group 0 is accompanied by an indication of the number of CDM groups of DM-RSs that do not have a PDSCH. UEs that are data scheduled using antenna ports from CDM group 1 may assume that the PDSCH is not mapped to resource elements associated with CDM group 0. UEs that are scheduled with data mapped to antenna ports in set {1000, 1001} or set {1002, 1003} are accompanied by an indication of whether ports in set {1004, 1005} or set {1006, 1007} ​​are used for transmission to other users. However, UEs that plan to transmit 3 or 4 layers using antenna ports indicated from sets {1000, 1001} and {1002, 1003} may assume SU-MIMO.

[0051] Non-transparent MU-MIMO has at least two advantages. One advantage is that if a UE scheduled for a single layer transmission on either antenna port 1000 or 1001 knows that antenna ports 1004 and 1005 are not used, it can resolve a length-4 OCC to be a length-2 OCC. This makes demodulation more robust to time-varying wireless channels. Another advantage is that UEs with advanced receivers (e.g., successive interference cancellation (SIC) receivers) can more efficiently cancel cross-layer interference resulting from transmissions to other users.

[0052] In another embodiment, the NR DM-RS sequence is generated as in TS 38.211, resulting in a quasi-orthogonal DM-RS between NR DM-RS Type 3 and LTE DM-RS. In one version of this embodiment, a length-4 OCC is applied to the CDM group as in TS 36.211, implying reliance on subcarrier and PRB index. In another version of this embodiment, a length-4 OCC is applied to the CDM group without reliance on subcarrier and PRB index.

[0053] In yet another embodiment, an NR UE configured with DM-RS type 3 can be further configured with at least one Rel-15 DM-RS type. This allows for MU-MIMO between NR UEs that do not support DM-RS type 3 (such as legacy NR UEs) and LTE UEs. The selection between DM-RS type 3 and other DM-RS types is done dynamically via DCI.

[0054] In Figure 7, the DMRS used by NR PDSCH demodulation is shown with the LTE CRS without PDSCH mapping (i.e., the PDSCH is rate-matched around the LTE CRS). LTE NR coexistence for MU-MIMO and the new NR DM-RS (Type 3) are the reference signal locations when using the LTE DM-RS definition.

[0055] As mentioned at the beginning of this section, LTE uses the DC subcarrier while NR does not, resulting in misaligned RB boundaries on one side of the DC subcarrier, as shown in Figure 8. When co-scheduling LTE and NR users in MU-MIMO mode, it can be beneficial to align the NR and LTE RBs, e.g., leaving empty RBs that only partially overlap with the RBs used for MU-MIMO RBs.

[0056] The above description focuses on DL. However, MU-MIMO is also possible in UL where the same UL time-frequency resources are used by multiple users simultaneously. It may also be beneficial here to be able to configure NR users with DM-RS that is orthogonal to the LTE DM-RS, e.g., DM-RS for DFT-spread PUSCH. LTE can be configured with DM-RS, whether on combs (every other subcarrier) or on all subcarriers. The first step is to make sure that the LTE and NR DM-RS are mapped to the same resource elements. Furthermore, LTE always uses a UL shift of 7.5 kHz, which in NR can and should be configured here.

[0057] In the LTE UL, the DM-RS is based on the Zadoff-Chu root sequence and its cyclic shifts.

[0058] The LTE UL DM-RS occurs in symbols 3 and 10 of an LTE subframe, and therefore the NR DM-RS must occur in the same symbols, i.e., symbols 3 and 10 of an NR slot.

[0059] The cyclic shift of the Zadoff-Chu sequence is given by: TIFF0007621353000014.tif1292 LTE, TIFF0007621353000015.tif1116 and Each of TIFF0007621353000016.tif1216 is the RRC that is configured and indicated in the DCI. PRS (n s ) is a hopping function based on a pseudorandom sequence and is defined in the LTE specification (section 5.5.2.1.1, 36.211). TIFF0007621353000017.tif1116+ TIFF0007621353000018.tif1216 may be an RRC configured for DM-RS in NR. The same hopping function n as in LTE PRS (n s ) is used in NR, the only difference being that n s n counts NR half slots. PRS (n s The initial value of the pseudo-random generator for may be an RRC configured in the NR UE.

[0060] The Zadoff-Chu root sequence index can hop over time (group and sequence hopping). The parameters required to configure the root index and the associated hopping can be RRC configured in the NR UE. If hopping is applied, the same hopping function as in LTE will be used.

[0061] The embodiment will now be further described with reference to the drawings.

[0062] FIG. 9 is a flow chart of an exemplary embodiment of a method performed by a wireless device operating in a communication system. The communication system includes a radio spectrum shared by multiple radio access technologies, which in some examples is referred to as coexistence. In other words, the communication system operates on or uses a radio spectrum shared by two or more radio access technologies (RATs), and the communication system uses two or more RATs in the same communication system. In some examples, the multiple radio access technologies include or are limited to LTE and NR. For example, LTE-NR coexistence. In some examples, the communication system supports multi-user multiple input multiple output (MIMO). The method begins in step 600 with the wireless device obtaining a configuration for a demodulation reference signal (DMRS). The DMRS comprises a pattern that uses common resource elements of at least two of the multiple radio access technologies. In other words, the DMRS occupies resource elements identified by the pattern, and at least one of the resource elements identified by the pattern is used or occupied by another radio access type. For example, a DMRS may be configured for a first radio access technology and occupy the same resource elements as a DMRS configured for a second radio access technology. For example, the DMRS may use common resource elements for LTE and NR. The method proceeds with the wireless device receiving or transmitting a data transmission based on the obtained demodulation reference signal at step 630. For example, the wireless device may receive a PDSCH transmission on NR while a coexisting LTE transmission is scheduled within the same spectrum / subcarrier range. For example, the wireless device demultiplexes data based on the configured DMRS. In other examples, the wireless device uses the DMRS configuration to transmit an NR transmission on a PUSCH using the same spectrum / subcarriers scheduled for LTE. In some examples, the DMRS is configured for a first radio access technology and is orthogonal or quasi-orthogonal to the DMRS configured for one or more of the multiple radio access technologies.In some examples, the DMRS is derived by code domain multiplexing (CDM) and uses the same DMRS sequence as the DMRS for another user, comprising a sequence with radio resource elements co-scheduled for another one of the multiple radio access technologies. In some examples, the DMRS comprises a time domain orthogonal cover code (OCC) of length 4 for a group of four resource elements or of length 2 for a group of two resource elements. For example, the OCC is applied on top of the DMRS sequence, effectively generating a new DMRS sequence. In some examples, a length 4 OCC is applied to one of the CDM groups, each CDM group corresponding to four unique antenna ports. In some examples, the method further / optionally includes obtaining (610) an antenna port indication. For example, this may be indicated to the wireless device. In some examples, this may be indicated by a network node, for example, in a radio resource control message (DCI) or the like. The antenna port indication can provide an indication of whether other ports in the same CDM group are scheduled. In some examples, the indication additionally or alternatively indicates the number of CDM groups for which data transmissions on the physical downlink shared channel are not scheduled. This is because a UE scheduled using all ports in a CDM group only needs to know whether ports in other CDM groups are scheduled for other users, while a UE scheduled using a subset of ports in a CDM group needs to know whether ports in the same and other CDM groups are scheduled for other users. In some examples, the CDM corresponds to an OCC of length 4, depending on the subcarrier and / or physical resource block index.In some examples, the obtained DMRS configuration is a first DMRS configuration, and the method further includes obtaining a second DMRS configuration, the second DMRS configured for different resource elements than the cell-specific reference signal configured for any one of the DMRS and the other radio access technology. For example, the second DMRS may be a NR Release 15 DM-RS type, which enables MU-MIMO between NR UEs (e.g., DM-RS type 3, such as legacy NR UEs) that do not support the first DMRS and LTE UEs, and in some examples, the method may further include receiving an indication to select between the first DMRS configuration and the second DMRS configuration (620). For example, this may be dynamically indicated to the wireless device via a DCI. In some examples, the above-described embodiments apply to DL MU-MIMO, while in other examples, the DMRS configuration is for uplink MU-MIMO.

[0063] FIG. 10 is a flow chart illustrating an exemplary embodiment of a method performed by a network node in a communication system. The communication system includes providing multi-RAT coexistence, in other words a radio spectrum shared by multiple radio access technologies such as LTE-NR coexistence. The method begins at step 700, where the network node determines a configuration of a demodulation reference signal (DMRS). The DMRS comprises a pattern that uses common resource elements of at least two of the multiple radio access technologies. In other words, the DMRS occupies resource elements identified by the pattern, and at least one of the resource elements identified by the pattern is used or occupied by another radio access type. For example, the DMRS may be configured for a first radio access technology and occupy the same resource elements as a DMRS configured for a second radio access technology. For example, the DMRS may be configured for resource elements common to both LTE and NR. The method proceeds to step 720, where the network node receives or transmits a data transmission based on the determined demodulation reference signal. For example, the network node receives an NR transmission on a PUSCH, also using spectrum / subcarriers scheduled for LTE. For example, the network node or base station uses the determined DMRS configuration to demultiplex the received PUSCH. In another example, the network node uses the determined DMRS configuration to schedule NR PDSCH transmissions to the wireless device while coexisting LTE transmissions in the same spectrum / subcarrier range are scheduled for other wireless devices. The method optionally includes step 710, where the network node configures the wireless device with the determined DMRS. For example, this may be for multi-user multiple-input multiple-output (MIMO) communications. In some examples, the DMRS is configured for a first radio access technology and is orthogonal or quasi-orthogonal to the DMRS configured for one or more of the multiple radio access technologies.In some examples, the DMRS comprises a sequence with code domain multiplexing (CDM) and co-scheduled radio resource elements for another one of the multiple radio access technologies derived by using the same DMRS sequence as the DMRS for another user. In some examples, the DMRS comprises a time domain orthogonal cover code (OCC) of length 4 for a group of four resource elements or of length 2 for a group of two resource elements. For example, the OCC is applied on top of the DMRS sequence, effectively generating a new DMRS sequence. In some examples, the length 4 OCC is applied to one of the CDM groups, each CDM group corresponding to four unique antenna ports. The method may optionally include step 730 of transmitting an antenna port indicator to the wireless device. In some examples, the antenna port indicator includes indicating whether other ports in the same CDM group are scheduled to be used. In some examples, the antenna port indicator includes indicating the number of CDM groups that do not have scheduled physical downlink shared channel data. In some examples, the CDM corresponds to a length 4 OCC depending on the subcarrier and / or physical resource block index. In some examples, the determined DMRS configuration is a first DMRS configuration, and the method further includes determining a second DMRS configuration, where the second DMRS is configured for unique resource elements from the DMRS and the cell-specific reference signal is configured for any one of the other radio access technologies. For example, the second DMRS may be a NR Release 15 DM-RS type. This enables MU-MIMO between NR UEs that do not support the first DMRS (e.g., DM-RS type 3, such as legacy NR UEs) and LTE UEs. In some examples, the method may further include transmitting an indication 740 to the wireless device to select between the first DMRS configuration and the second DMRS configuration. For example, this may be dynamically indicated to the wireless device via a DCI.In some examples, the above described embodiments apply to DL MU-MIMO, while in other examples the DMRS configuration is for uplink MU-MIMO.

[0064] Although the subject matter described herein may be implemented in any suitable type of system using any suitable components, the embodiments disclosed herein are further described in connection with a wireless network, such as the exemplary wireless network or communication system shown in FIG. 11. For simplicity, the wireless network of FIG. 11 shows only network 106, network nodes 160 and 160b, and wireless devices 110, 110b, and 100c. In practice, the wireless network may further include any additional elements suitable for supporting communications between wireless devices, or between wireless devices and other communication devices, such as, for example, landlines, service providers, or any other network nodes or end devices. Of the illustrated components, network node 160 and wireless device 110 are depicted with additional details. The wireless network may provide communication and other types of services to one or more wireless devices to facilitate the wireless devices' access to and / or use of services provided by or via the wireless network.

[0065] A wireless network may comprise and / or interface with any type of communication, telecommunication, data, cellular, and / or wireless network or other similar type of system. In some embodiments, a wireless network may be configured to operate according to a particular standard or other type of predefined rules or procedures. Thus, certain embodiments of a wireless network may implement a communication standard, such as Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Long Term Evolution (LTE), and / or other suitable 2G, 3G, 4G, or 5G standard, a wireless local area network (WLAN) standard, such as the IEEE 802.11 standard, and / or any other suitable wireless communication standard, such as Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, and / or ZigBee standards.

[0066] The network 106 may include one or more backhaul networks, core networks, IP networks, public switched telephone networks (PSTN), packet data networks, optical networks, wide area networks (WANs), local area networks (LANs), wireless local area networks (WLANs), wired networks, wireless networks, metropolitan area networks, and other networks that enable communication between devices.

[0067] The network node 160 and the wireless device 110 comprise various components, which are described in more detail below. These components cooperate to provide network node and / or wireless device functionality, such as providing wireless connectivity in a wireless network. In various embodiments, a wireless network may comprise any number of wired or wireless networks, network nodes, base stations, controllers, wireless devices, relay stations, and / or any other components or systems that may facilitate or participate in communication of data and / or signals, whether via wired or wireless connections.

[0068] In FIG. 11, network node 160 includes processing circuitry 170, device readable medium 180, interface 190, auxiliary device 184, power source 186, power circuitry 187, and antenna 162. As previously mentioned, a network node may be connected to a non-terrestrial network, such as that shown in FIG. 1, for example, but while network node 160 shown in the exemplary wireless network of FIG. 1 may represent a device including the illustrated combination of hardware components, other embodiments may include network nodes having different combinations of components. It should be understood that a network node comprises any suitable combination of hardware and / or software required to perform the tasks, features, functions, and methods disclosed herein. Additionally, although the components of network node 160 are shown as a single box disposed within a larger box or nested within multiple boxes, in reality a network node may comprise multiple different physical components that make up the single illustrated component (e.g., device readable medium 180 may comprise multiple separate hard disk drives and multiple RAM modules).

[0069] Similarly, the network node 160 may be comprised of multiple physically separate components (e.g., a NodeB component and an RNC component, or a BTS component and a BSC component, etc.), each of which may have their own respective components. In certain scenarios where the network node 160 includes multiple separate components (e.g., a BTS and a BSC component), one or more separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such scenarios, each unique NodeB and RNC pair may be considered as one individual network node. In certain embodiments, the network node 160 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate device-readable media 180 for different RATs) and some components may be reused (e.g., the same antenna 162 may be shared by the RATs). The network node 160 may also include multiple sets of the various illustrated components for different wireless technologies integrated into the network node 160, such as, for example, GSM, WCDMA, LTE, NR, WiFi, or Bluetooth wireless technologies. These radio technologies may be integrated into the same or different chips or chipsets and other components within the network node 160.

[0070] Processing circuitry 170 is configured to perform any decision, calculation, or similar operation (e.g., a particular acquisition operation) described herein as being provided by a network node. These operations performed by processing circuitry 170 may include, for example, processing the information acquired by processing circuitry 170 by transforming the acquired information to other information, comparing the acquired or transformed information to information stored in the network node, and / or performing one or more operations based on the acquired or transformed information and making a decision as a result of the processing.

[0071] The processing circuitry 170 may comprise one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software, and / or coded logic operable to provide, either alone or in conjunction with other network node 160 components, such as device readable medium 180, functionality of the network node 160, etc. For example, the processing circuitry 170 may execute instructions stored on the device readable medium 180 or memory within the processing circuitry 170. Such functionality may include providing any of the various wireless features, functions, or benefits described herein. In some embodiments, the processing circuitry 170 may include a system on a chip (SOC).

[0072] In some embodiments, the processing circuitry 170 may include one or more of radio frequency (RF) transceiver circuitry 172 and baseband processing circuitry 174. In some embodiments, the radio frequency (RF) transceiver circuitry 172 and the baseband processing circuitry 174 may be on separate chips (or sets of chips), boards, or units, such as a radio unit and a digital unit. In alternative embodiments, some or all of the RF transceiver circuitry 172 and the baseband processing circuitry 174 may be on the same chip or set of chips, boards, or units.

[0073] In some embodiments, some or all of the functionality described herein as being provided by a network node, base station, eNB, or other such network device may be performed by the processing circuitry 170 executing instructions stored on the device-readable medium 180 or memory in the processing circuitry 170. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry 170 without executing instructions stored on a separate or distinct device-readable medium, such as in a hardwired manner. In any of these embodiments, the processing circuitry 170 may be configured to perform the described functionality, whether or not it executes instructions stored on a device-readable storage medium. For example, the processing circuitry 170 may be configured to determine an estimate of a Doppler shift for transmissions between the network node and a wireless device. The processing circuitry may then be configured to transmit a frequency adjustment indication to the wireless device based on the determined estimate of the Doppler shift. Benefits provided by such functionality are not limited to the processing circuitry 170 alone or other components of the network node 160, but are enjoyed by the network node 160 as a whole, and / or by end users and the wireless network as a whole.

[0074] The device readable medium 180 may include any form of volatile or non-volatile computer readable memory, including, but not limited to, persistent storage, solid state memory, remotely mounted memory, magnetic media, optical media, random access memory, read only memory, mass storage media (e.g., hard disks), removable storage media (e.g., flash drives, compact discs (CDs) or digital video discs (DVDs)), and / or other volatile or non-volatile, non-transitory device readable and / or computer executable memory devices that store information, data, and / or instructions that may be used by the processing circuitry 170. The device readable medium 180 may store any suitable instructions, data, or information, including applications including one or more of computer programs, software, logic, rules, codes, tables, etc., and / or other instructions that may be executed by the processing circuitry 170 and utilized by the network node 160. The device readable medium 180 may be used to store any calculations performed by the processing circuitry 170 and / or any data received via the interface 190. In some embodiments, the processing circuitry 170 and the device-readable medium 180 may be considered to be integrated.

[0075] The interface 190 is used for wired or wireless communication of signaling and / or data between the network node 160, the network 106, and / or the wireless device 110. As shown, the interface 190 includes a port / terminal 194 for transmitting and receiving data to and from the network 106, for example, via a wired connection. The interface 190 may also be coupled to a portion of the antenna 162, or in a particular embodiment, includes a wireless front-end circuit 192. The wireless front-end circuit 192 includes a filter 198 and an amplifier 196. The wireless front-end circuit 192 may be connected to the antenna 162 and the processing circuit 170. The wireless front-end circuit may be configured to condition signals communicated between the antenna 162 and the processing circuit 170. The wireless front-end circuit 192 may receive digital data to be sent to other network nodes or wireless devices via a wireless connection. The wireless front-end circuit 192 may convert the digital data into a wireless signal having appropriate channel and bandwidth parameters using a combination of the filter 198 and / or amplifier 196. The wireless signal may then be transmitted via antenna 162. Similarly, when receiving data, antenna 162 collects the wireless signal which is then converted to digital data by wireless front-end circuitry 192. The digital data may be passed to processing circuitry 170. In other embodiments, the interface may include different components and / or different combinations of components.

[0076] In certain alternative embodiments, network node 160 may not include a separate radio front-end circuit 192; instead, processing circuitry 170 may include radio front-end circuitry and may be connected to antenna 162 without a separate radio front-end circuitry 192. Similarly, in some embodiments, all or some of RF transceiver circuitry 172 may be considered part of interface 190. In still other embodiments, interface 190 may include one or more ports or terminals 194, radio front-end circuitry 192, and RF transceiver circuitry 172 as part of a radio unit (not shown), and interface 190 may communicate with baseband processing circuitry 174 that is part of a digital unit (not shown).

[0077] Antenna 162 may include one or more antennas, or an antenna array, configured to transmit and / or receive wireless signals. Antenna 162 may be coupled to radio front-end circuitry 190 and may be any type of antenna capable of wirelessly transmitting and receiving data and / or signals. In some embodiments, antenna 162 may include one or more omni-directional, sector, or panel antennas operable to transmit and receive wireless signals between 2 GHz and 66 GHz, for example. An omni-directional antenna may be used to transmit and receive wireless signals in any direction, a sector antenna may be used to transmit and receive wireless signals from devices in a particular area, and a panel antenna may be a line-of-sight antenna used to transmit and receive wireless signals in a relatively straight line. In some examples, the use of more than one antenna may be referred to as MIMO. In some embodiments, antenna 162 may be separate from network node 160 and may be connectable to network node 160 via an interface or port.

[0078] The antenna 162, the interface 190, and / or the processing circuit 170 may be configured to perform any receiving operation and / or a particular acquisition operation described herein as being performed by a network node. Any information, data, and / or signal may be received from a wireless device, another network node, and / or any other network equipment. Similarly, the antenna 162, the interface 190, and / or the processing circuit 170 may be configured to perform any transmitting operation described herein as being performed by a network node. Any information, data, and / or signal may be transmitted to a wireless device, another network node, and / or any other network equipment.

[0079] The power supply circuit 187 may comprise or be coupled to a power management circuit and is configured to provide power to the components of the network node 160 to perform the functions described herein. The power supply circuit 187 may receive power from a power source 186. The power source 186 and / or the power supply circuit 187 may be configured to provide power to the various components of the network node 160 in a form suitable for each component (e.g., voltage and current levels required by each component), and the power source 186 may be included in the power supply circuit 187 and / or the network node 160, or may be included external to the power supply circuit. For example, the network node 160 may be connectable to an external power source (e.g., an electrical outlet) via an input circuit or interface such as an electrical cable, whereby the external power source provides power to the power supply circuit 187. As a further example, the power supply 186 may include a power source in the form of a battery or battery pack connected to or integrated with the power supply circuit 187. In the event of a failure of the external power source, a backup power may be provided from the battery. Other types of power sources, such as photovoltaic devices, may also be used.

[0080] Alternative embodiments of network node 160 may include additional components beyond those shown in Figure 11 that may be responsible for providing certain aspects of the network node's functionality, including any of the functionality described herein and / or any functionality necessary to support the subject matter described herein. For example, network node 160 may include user interface devices that allow for the input of information into network node 160 and the output of information from network node 160, thereby enabling a user to perform diagnostics, maintenance, repair, and other management functions on network node 160.

[0081] As shown, wireless device 110 includes antenna 111, interface 114, processing circuitry 120, device-readable medium 130, user interface equipment 132, auxiliary equipment 134, power source 136, and power circuitry 137. Wireless device 110 may include one or more sets of the illustrated components for different wireless technologies supported by wireless device 110, such as, for example, GSM, WCDMA, LTE, NR, WiFi, WiMAX, or Bluetooth wireless technologies, just to name a few. These wireless technologies may be integrated on the same or different chip or set of chips as other components in wireless device 110.

[0082] Antenna 111 may include one or more antennas or antenna arrays configured to transmit and / or receive wireless signals and is connected to interface 114. In certain alternative embodiments, antenna 111 may be separate from wireless device 110 and may be connectable to wireless device 110 via an interface or port. Antenna 111, interface 114, and / or processing circuitry 120 may be configured to perform any receiving or transmitting operations described herein as being performed by a wireless device. Any information, data, and / or signal may be received from a network node and / or another wireless device. In some embodiments, the wireless front-end circuitry and / or antenna 111 may be considered an interface.

[0083] As shown, the interface 114 includes a radio front-end circuit 112 and an antenna 111. The radio front-end circuit 112 includes one or more filters 118 and an amplifier 116. The radio front-end circuit 114 is coupled to the antenna 111 and the processing circuit 120 and configured to condition signals communicated between the antenna 111 and the processing circuit 120. The radio front-end circuit 112 may be coupled to or part of the antenna 111. In some embodiments, the wireless device 110 may not include a separate radio front-end circuit 112; rather, the processing circuit 120 may include a radio front-end circuit and may be connected to the antenna 111. Similarly, in some embodiments, some or all of the RF transceiver circuit 122 may be considered part of the interface 114. The radio front-end circuit 112 may receive digital data that is sent over a wireless connection to another network node or wireless device. The radio front-end circuitry 112 can convert the digital data into a radio signal having appropriate channel and bandwidth parameters using a combination of filters 118 and / or amplifiers 116. The radio signal may then be transmitted via the antenna 111. Similarly, when receiving data, the antenna 111 collects the radio signal which is then converted into digital data by the radio front-end circuitry 112. The digital data can be passed to the processing circuitry 120. In other embodiments, the interface may include different components and / or different combinations of components.

[0084] The processing circuitry 120 may comprise one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software, and / or coded logic operable to provide, either alone or in conjunction with other wireless device 110 components, such as the device readable medium 130, the functionality of the wireless device 110. Such functionality may include providing any of the various wireless features or advantages described herein. For example, the processing circuitry 120 may execute instructions stored on the device readable medium 130 or memory within the processing circuitry 120 to provide the functionality disclosed herein.

[0085] As shown, the processing circuitry 120 includes one or more of an RF transceiver circuitry 122, a baseband processing circuitry 124, and an application processing circuitry 126. In other embodiments, the processing circuitry may include different components and / or different combinations of components. In some embodiments, the processing circuitry 120 of the wireless device 110 may comprise a SOC. In some embodiments, the RF transceiver circuitry 122, the baseband processing circuitry 124, and the application processing circuitry 126 may be on separate chips or chipsets. In alternative embodiments, some or all of the baseband processing circuitry 124 and the application processing circuitry 126 may be combined into one chip or set of chips, and the RF transceiver circuitry 122 may be located on a separate chip or set of chips. In further alternative embodiments, some or all of the RF transceiver circuitry 122 and the baseband processing circuitry 124 may be on the same chip or set of chips, and the application processing circuitry 126 may be on a separate chip or set of chips. In yet other alternative embodiments, some or all of the RF transceiver circuitry 122, the baseband processing circuitry 124, and the application processing circuitry 126 may be combined on the same chip or chipset. In some embodiments, the RF transceiver circuitry 122 may be part of the interface 114. The RF transceiver circuitry 122 may condition the RF signals for the processing circuitry 120.

[0086] In certain embodiments, some or all of the functionality described herein as being performed by the wireless device may be provided by the processing circuitry 120 executing instructions stored on the device-readable medium 130, which in certain embodiments may be a computer-readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry 120 without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hardwired manner. In any of these particular embodiments, the processing circuitry 120 may be configured to perform the described functionality, regardless of whether or not it executes instructions stored on the device-readable storage medium. For example, the processing circuitry 120 may be configured to obtain a frequency offset corresponding to a Doppler shift in transmit and receive frequencies between the wireless device and a non-terrestrial network that is an NTN including network nodes and communications satellites, where the network nodes are one of a terrestrial base station and a satellite base station or a satellite gateway. The processing circuitry 120 may then be configured to apply the frequency offset to an uplink transmission to the network node. The advantages provided by such functionality are not limited to the processing circuit 120 alone or other components of the wireless device 110, but are enjoyed by the wireless device 110 as a whole, and / or by end users and the wireless network as a whole.

[0087] Processing circuitry 120 may be configured to perform any determining, calculating, or similar operation (e.g., certain acquisition operations) described herein as being performed by a wireless device. These operations, as performed by processing circuitry 120, may include processing the information obtained by processing circuitry 120, for example, by transforming the obtained information into other information, comparing the obtained or transformed information with information stored by wireless device 110, and / or performing one or more operations based on the obtained or transformed information, and making a determination as a result of said processing.

[0088] The device-readable medium 130 may be operable to store applications including one or more of computer programs, software, logic, rules, codes, tables, etc., and / or other instructions capable of being executed by the processing circuit 120. The device-readable medium 130 may include computer memory (e.g., random access memory (RAM) or read-only memory (ROM)), mass storage media (e.g., hard disk), removable storage media (e.g., compact disc (CD) or digital video disc (DVD)), and / or any other volatile or non-volatile, non-transitory device-readable and / or computer-executable memory device that stores information, data, and / or instructions that may be used by the processing circuit 120. In some embodiments, the processing circuit 120 and the device-readable medium 130 may be considered to be integrated.

[0089] The user interface equipment 132 may provide components that allow a human user to interact with the wireless device 110. Such interaction may be in many forms, such as visual, auditory, tactile, etc. The user interface equipment 132 may be operable to generate output to the user and allow the user to provide input to the wireless device 110. The type of interaction may vary depending on the type of user interface equipment 132 installed on the wireless device 110. For example, if the wireless device 110 is a smartphone, the interaction may be via a touch screen, and if the wireless device 110 is a smart meter, the interaction may be via a screen that provides usage (e.g., number of gallons used), or a speaker that provides an audible alarm (e.g., if smoke is detected). The user interface equipment 132 may include input interface devices and circuits, as well as output interface devices and circuits. The user interface equipment 132 is configured to allow input of information to the wireless device 110 and is connected to the processing circuit 120 to allow the processing circuit 120 to process the input information. The user interface equipment 132 may include, for example, a microphone, proximity or other sensors, keys / buttons, a touch display, one or more cameras, a USB port, or other input circuitry. The user interface equipment 132 is also configured to enable output of information from the wireless device 110 and to enable the processing circuitry 120 to output information from the wireless device 110. The user interface equipment 132 may include, for example, a speaker, a display, vibration circuitry, a USB port, a headphone interface, or other output circuitry. Using one or more input / output interfaces, devices, and circuits of the user interface equipment 132, the wireless device 110 may communicate with an end user and / or a wireless network, and may provide the end user and / or the wireless network with the benefit of the functionality described herein.

[0090] The auxiliary device 134 is operable to provide more specific functions that may not typically be performed by wireless devices. It may include specialized sensors for taking measurements for various purposes, interfaces for additional types of communication, such as wired communication, etc. The inclusion and type of components of the auxiliary device 134 may vary depending on the embodiment and / or scenario.

[0091] The power source 136 may be in the form of a battery or battery pack in some embodiments. Other types of power sources, such as an external power source (e.g., an electrical outlet), a photovoltaic device, or a power cell, may also be used. The wireless device 110 may further comprise a power circuit 137 for delivering power from the power source 136 to various portions of the wireless device 110 that require power from the power source 136 and for performing any of the functions described or illustrated herein. The power circuit 137 may comprise a power management circuit in certain embodiments. The power circuit 137 may additionally or alternatively be operable to receive power from an external power source, in which case the wireless device 110 may be connectable to an external power source (such as an electrical outlet) via an interface, such as an input circuit or a power cable. The power circuit 137 may also be operable in certain embodiments to deliver power from the external power source to the power source 136. This may be for charging the power source 136, for example. The power circuit 137 may perform any formatting, conversion, or other modification of the power from the power source 136 to make it suitable for the respective components of the wireless device 110 to be powered.

[0092] FIG. 12 illustrates an embodiment of a UE according to various aspects described herein. As used herein, user equipment or UE does not necessarily have a user in the sense of a human user who owns and / or operates an associated device. Instead, a UE may represent a device that is intended for sale to or operation by a human user, but may or may not initially be associated with a particular human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to or operation by an end user, but may be associated with or operated for a user (e.g., a smart power meter). The UE 2200 may be any UE identified by the 3rd Generation Partnership Project (3GPP), including an NB-IoT UE, a Machine Type Communication (MTC) UE, and / or an enhanced MTC (eMTC) UE. As shown in Figure 9, UE 200 is an example of a wireless device configured to communicate according to one or more communications standards promulgated by the 3rd Generation Partnership Project (3GPP®), such as the 3GPP® GSM, UMTS, LTE, and / or 5G standards. As mentioned above, the terms "wireless device" and "UE" may be used interchangeably. Thus, although Figure 9 is a UE, the components described herein are equally applicable to a wireless device and vice versa.

[0093] In FIG. 12, a UE 200 includes a processing circuit 201 operatively coupled to an input / output interface 205, a radio frequency (RF) interface 209, a network connection interface 211, a memory 215 including a random access memory (RAM) 217, a read only memory (ROM) 219, and a communication subsystem 231, a power source 233, and / or any other components, such as a storage medium 221, or any combination thereof. The storage medium 221 includes an operating system 223, an application program 225, and data 227. In other embodiments, the storage medium 221 may include other similar types of information. Some UEs may utilize all of the components shown in FIG. 9, or only a subset of the components. The level of integration between the components may vary from UE to UE. Additionally, some UEs may include multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

[0094] In Fig. 12, processing circuitry 201 may be configured to process computer instructions and data. Processing circuitry 201 may be configured to implement any sequential state machine operable to execute machine instructions stored in memory as a machine-readable computer program, such as one or more hardware implemented state machines (e.g., discrete logic, FPGA, ASIC, etc.), programmable logic with appropriate firmware, one or more stored programs, general purpose processors such as microprocessors or digital signal processors (DSPs), as well as appropriate software, or any combination of the above. For example, processing circuitry 201 may include two central processing units (CPUs). Data may be information in a form suitable for use by a computer.

[0095] In the illustrated embodiment, the input / output interface 205 may be configured to provide a communication interface to an input device, an output device, or an input and output device. The UE 200 may be configured to use an output device via the input / output interface 205. The output device may use the same type of interface port as the input device. For example, a USB port may be used to provide input to the UE 200 and output from the UE. The output device may be a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smart card, another output device, or any combination thereof. The UE 200 may be configured to allow a user to capture information into the UE 200 using an input device via the input / output interface 205. The input device may include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a webcam, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smart card, etc. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from the user. The sensor may be, for example, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, another like sensor, or any combination thereof. For example, the input device may be an accelerometer, a magnetometer, a digital camera, a microphone, and an optical sensor.

[0096] In FIG. 12, the RF interface 209 may be configured to provide a communication interface to RF components such as a transmitter, a receiver, and an antenna. The network connection interface 211 may be configured to provide a communication interface to a network 243a. The network 243a may include wired and / or wireless networks such as a local area network (LAN), a wide area network (WAN), a computer network, a wireless network, a telecommunications network, other networks, or combinations thereof. For example, the network 243a may comprise a Wi-Fi network. The network connection interface 211 may be configured to include receiver and transmitter interfaces used to communicate with one or more other devices over a communication network according to one or more communication protocols such as Ethernet, TCP / IP, SONET, ATM, etc. The network connection interface 211 may implement receiver and transmitter functions appropriate for a communication network link (e.g., optical, electrical, etc.). The transmitter functions and receiver functions may share circuit components, software, or firmware, or may be implemented separately.

[0097] The RAM 217 can be configured to interface to the processing circuit 201 via the bus 202 to provide storage or caching of data or computer instructions during execution of software programs such as an operating system, application programs, and device drivers. The ROM 219 can be configured to provide computer instructions or data to the processing circuit 201. For example, the ROM 219 can be configured to store unchanging low-level system code or data for basic system functions such as basic input / output, startup, or receiving keystrokes from a keyboard, stored in a non-volatile memory. The storage medium 221 can be configured to include memory such as RAM, ROM, programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disk, optical disk, floppy disk, hard disk, removable cartridge, or flash drive. In one example, the storage medium 221 can be configured to include an operating system 223, an application program 225 such as a web browser application, a widget or gadget engine or another application, and data files 227. The storage medium 221 may store any of a variety of operating systems or combinations of operating systems for use by the UE 200.

[0098] The storage medium 221 may be configured to include multiple physical drive units, such as a redundant array of independent disks (RAID), a floppy disk drive, a flash memory, a USB flash drive, an external hard disk drive, a thumb drive, a pen drive, a key drive, a high density digital versatile disk (HD-DVD) optical disk drive, an internal hard disk drive, a Blu-ray optical disk drive, a holographic digital data storage (HDDS) optical disk drive, an external mini dual in-line memory module (DIMM), a synchronous dynamic random access memory (SDRAM), an external micro-DIMM SDRAM, a smart card memory such as a subscriber identity module or a removable user identity (SIM / RUIM) module, other memory, or any combination thereof. The storage medium 221 may enable the UE 200 to access, offload data, or upload data to computer executable instructions, application programs, and the like stored in a temporary or non-transitory memory medium. An article of manufacture, such as one utilizing a communication system, may be tangibly embodied in the storage medium 221, which may comprise a device-readable medium.

[0099] In FIG. 12, the processing circuit 201 may be configured to communicate with the network 243b using the communication subsystem 231. The network 243a and the network 243b may be the same or different networks or networks. The communication subsystem 231 may be configured to include one or more transceivers used to communicate with the network 243b. For example, the communication subsystem 231 may be configured to include one or more transceivers used to communicate with one or more remote transceivers of another device capable of wireless communication, such as another wireless device, UE, or base station of a radio access network (RAN), according to one or more communication protocols, such as IEEE 802.2, CDMA, WCDMA, GSM, LTE, UTRAN, WiMax, etc. Each transceiver may include a transmitter 233 and / or a receiver 235 to respectively perform transmitter or receiver functions (e.g., frequency allocation, etc.) appropriate for the RAN link. Additionally, the transmitter 233 and receiver 235 of each transceiver may share circuit components, software, or firmware, or may be implemented separately.

[0100] In the illustrated embodiment, the communication capabilities of the communication subsystem 231 may include data communications, voice communications, multimedia communications, short-range communications such as Bluetooth, short-range communications, location-based communications such as using a global positioning system (GPS) to determine location, another similar communication capability, or any combination thereof. For example, the communication subsystem 231 may include cellular communications, Wi-Fi communications, Bluetooth communications, and GPS communications. The network 243b may include wired and / or wireless networks such as a local area network (LAN), a wide area network (WAN), a computer network, a wireless network, a telecommunications network, other similar networks, or any combination thereof. For example, the network 243b may be a cellular network, a Wi-Fi network, and / or a short-range wireless network. The power source 213 may be configured to provide alternating current (AC) or direct current (DC) power to the components of the UE 200.

[0101] The features, advantages, and / or functions described herein may be implemented in one of the components of the UE 200 or may be partitioned across multiple components of the UE 200. Furthermore, the features, advantages, and / or functions described herein may be implemented in any combination of hardware, software, or firmware. In one example, the communication subsystem 231 may be configured to include any of the components described herein. Furthermore, the processing circuit 201 may be configured to communicate with any of such components via the bus 202. In another example, any of such components may be represented by program instructions stored in memory that, when executed by the processing circuit 201, perform the corresponding functions described herein. In another example, the functions of any of such components may be partitioned between the processing circuit 201 and the communication subsystem 231. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware, and computationally intensive functions may be implemented in hardware.

[0102] 13 is a schematic block diagram illustrating a virtualization environment 300 in which functions performed by some embodiments can be virtualized. In this context, virtualization creates a device or a virtualized version of a device, which may include virtualization of hardware platforms, storage, and network resources. As used herein, virtualization can be applied to a node (e.g., a virtualized base station or a virtualized radio access node) or device (e.g., a UE, a wireless device, or any other type of communication device) or components thereof, and relates to embodiments in which at least a portion of the functionality is implemented as one or more virtual components (e.g., via one or more applications, components, functions, virtual machines, or containers running on one or more physical processing nodes in one or more networks).

[0103] In some embodiments, some or all of the functionality described herein may be implemented as virtual components executed by one or more virtual machines implemented within one or more virtual environments 300 hosted by one or more hardware nodes 330. Additionally, in embodiments where the virtual nodes are not wireless access nodes or do not require wireless connectivity (e.g., core network nodes), the network nodes may be fully virtualized.

[0104] The functionality may be implemented by one or more applications 320 (which may alternatively be referred to as software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) that operate to implement some of the features, functions, and / or benefits of the embodiments disclosed herein. The applications 320 execute in a virtualization environment 300 that provides hardware 330 with processing circuitry 360 and memory 390. The memory 390 includes instructions 395 executable by the processing circuitry 360 such that the applications 320 are operable to provide one or more of the features, advantages, and / or functions disclosed herein.

[0105] The virtualization environment 300 comprises a general-purpose or dedicated network hardware device 330 comprising a set of one or more processors or processing circuits 360, which may be commercial off-the-shelf (COTS) processors, application specific integrated circuits (ASICs), or any other type of processing circuitry including digital or analog hardware components or dedicated processors. Each hardware device may comprise a memory 390-1, which may be a non-persistent memory for temporarily storing instructions 395 or software executed by the processing circuits 360. Each hardware device may include one or more network interface controllers (NICs) 370, also referred to as network interface cards, including a physical network interface 380. Each hardware device may also include a non-transitory, persistent, machine-readable storage medium 390-2 having stored thereon software 395 and / or instructions executable by the processing circuits 360. The software 395 may include any type of software, including software for instantiating one or more virtualization layers 350 (also referred to as hypervisors), software for running virtual machines 340, and software enabling the implementation of the functions, features, and / or benefits described in connection with some embodiments described herein.

[0106] A virtual machine 340 may include virtual processing, virtual memory, virtual networking or interfaces, and virtual storage, and may be executed by a corresponding virtualization layer 350 or hypervisor. Various embodiments of an instance of a virtual appliance 320 may be implemented on one or more virtual machines 340, and the implementation may be done in different ways.

[0107] During operation, the processing circuitry 360 executes software 395 to instantiate a hypervisor or virtualization layer 350, sometimes referred to as a virtual machine monitor (VMM), which can present a virtual operating platform to the virtual machines 340 that appears as network hardware.

[0108] As shown in Figure 10, the hardware 330 may be a standalone network node with generic or specific components. The hardware 330 may be equipped with an antenna 3225 and may implement some functions via virtualization. Alternatively, the hardware 330 may be part of a larger hardware cluster (e.g., in a data center or customer premises equipment (CPE)) where many hardware nodes work together and are managed via a management and orchestration (MANO) 3100 that oversees, among other things, the lifecycle management of the application 320.

[0109] Hardware virtualization occurs in some contexts where it is called network functions virtualization (NFV). NFV can be used to consolidate many network equipment types onto industry-standard high-volume server hardware, physical switches, and physical storage that can be located in a data center, as well as customer premises equipment.

[0110] In the context of NFV, a virtual machine 340 may be a software implementation of a physical machine that executes programs as if they were running on a physical, non-virtualized machine. Each virtual machine 340, and that portion of hardware 330 on which it runs, is hardware dedicated to that virtual machine and / or hardware shared by that virtual machine with others of virtual machines 340, forms a separate Virtual Network Element (VNE).

[0111] Further, in the context of NFV, a Virtual Network Function (VNF) runs on one or more virtual machines 340 on the hardware network infrastructure 330 and is responsible for handling a particular network function corresponding to an application 320 in FIG. 10 .

[0112] In some embodiments, one or more radio units 3200, each including one or more transmitters 3220 and one or more receivers 3210, may be coupled to one or more antennas 3225. The radio units 3200 may communicate directly with the hardware node 330 via one or more suitable network interfaces, and may be used in combination with virtual components to provide radio functions to the virtual nodes, such as a radio access node or base station.

[0113] In some embodiments, some signals may be implemented using the control system 3230 which may alternatively be used for communication between the hardware node 330 and the wireless unit 3200.

[0114] Referring to Fig. 14, according to one embodiment, a communication system includes a telecommunications network 410, such as a 3GPP type cellular network, comprising an access network 411, such as a radio access network, and a core network 414. The access network 411 comprises a number of base stations 412a, 412b, 412c, such as NBs, eNBs, gNBs, or other types of wireless access points, each defining a corresponding coverage area 413a, 413b, 413c. Each base station 412a, 412b, 412c is connectable to the core network 414 via a wired or wireless connection 415. A first UE 491 located in the coverage area 413c is configured to be wirelessly connected or paged to the corresponding base station 412c. A second UE 492 in the coverage area 413a is wirelessly connectable to the corresponding base station 412a. Although multiple UEs 491, 492 are shown in this example, the disclosed embodiments are equally applicable to situations where only one UE is within the coverage area or is connected to a corresponding base station 412.

[0115] The telecommunications network 410 is itself connected to a host computer 430, which may be embodied in hardware and / or software of a standalone server, a cloud-implemented server, a distributed server, or processing resources in a server farm. The host computer 430 may be under the ownership or control of a service provider, or may be operated by or on behalf of the service provider. The connections 421 and 422 between the telecommunications network 410 and the host computer 430 may extend directly from the core network 414 to the host computer 430, or may go through an optional intermediate network 420. The intermediate network 420 may be one or more combinations of public, private, or hosted networks. The intermediate network 420, if any, may be a backbone network or the Internet. Notably, the intermediate network 420 may include two or more sub-networks (not shown).

[0116] The overall communication system of FIG. 14 enables connectivity between the connected UEs 491, 492 and the host computer 430. The connectivity can be described as an over-the-top (OTT) connection 450. The host computer 430 and the connected UEs 491, 492 are configured to communicate data and / or signals via the OTT connection 450 using the access network 411, the core network 414, any intermediate networks 420, and possible further infrastructure (not shown) as intermediaries. The OTT connection 450 can be transparent in the sense that the participating communication devices through which the OTT connection 450 passes are unaware of the routing of the uplink and downlink communications. For example, the base station 412 may need to be informed about the past routing of the incoming downlink communication with data originating from the host computer 430 to be forwarded (e.g., handed over) to the connected UE 491. Similarly, the base station 412 does not need to be aware of the future routing of outgoing uplink communications originating from the UE 491 towards the host computer 430 .

[0117] An embodiment of the UE, base station and host computer discussed in the preceding paragraphs will now be described with reference to FIG. 15. In the communication system 500, the host computer 510 includes hardware 515 including a communication interface 516 configured to set up and maintain wired or wireless connections with interfaces of different communication devices of the communication system 500. The host computer 510 further comprises a processing circuit 518 that may have storage and / or processing capabilities. In particular, the processing circuit 518 may include one or more programmable processors, application specific integrated circuits, field programmable gate arrays or combinations thereof (not shown) configured to execute instructions. The host computer 510 further comprises software 511, which is stored in or accessible to the host computer 510 and executable by the processing circuit 518. The software 511 includes a host application 512. The host application 512 is operable to provide services to a remote user, such as a UE 530 and a UE 530 connecting via an OTT connection 550 terminating at the host computer 510. In providing services to a remote user, the host application 512 may provide user data that is transmitted using the OTT connection 550 .

[0118] The communication system 500 further includes a base station 520 provided in the telecommunications system and comprising hardware 525 enabling communication with the host computer 510 and the UE 530. The hardware 525 may include a communication interface 526 for setting up and maintaining wired or wireless connections with interfaces of different communication devices of the communication system 500, as well as a wireless interface 527 for setting up and maintaining at least a wireless connection 570 with a UE 530 located within a coverage area (not shown in FIG. 12) served by the base station 520. The communication interface 526 may be configured to facilitate a connection 560 to the host computer 510. The connection 560 may be direct, may pass through a core network (not shown in FIG. 12) of the telecommunications system, and / or may pass through one or more intermediate networks external to the telecommunications system. In the illustrated embodiment, the hardware 525 of the base station 520 further includes a processing circuit 528, which may include one or more programmable processors, application specific integrated circuits, field programmable gate arrays, or combinations thereof (not shown) adapted to execute instructions. The base station 520 further comprises software 521 stored internally or accessible via an external connection.

[0119] The communication system 500 further includes the UE 530 already mentioned. Its hardware 535 may include a wireless interface 537 configured to set up and maintain a wireless connection 570 with a base station serving the coverage area in which the UE 530 is currently located. The hardware 535 of the UE 530 further includes a processing circuit 538, which may comprise one or more programmable processors, application specific integrated circuits, field programmable gate arrays, or combinations thereof (not shown) adapted to execute instructions. The UE 530 further comprises software 531, which may be stored or accessible to the UE 530 and executable by the processing circuit 538. The software 531 includes a client application 532. The client application 532 may be operable to provide services to a human or non-human user via the UE 530 with the support of the host computer 510. In the host computer 510, an executing host application 512 may communicate with the executing client application 532 via the UE 530 and an OTT connection 550 terminating at the host computer 510. In providing services to a user, the client application 532 can receive request data from the host application 512 and provide user data in response to the request data. The OTT connection 550 can transport both the request data and the user data. The client application 532 can interact with the user to generate the user data that it provides.

[0120] It should be noted that the host computer 510, base station 520, and UE 530 shown in Figure 12 may be similar to or identical to the host computer 430, one of the base stations 412a, 412b, 412c, and one of the UEs 491, 492 of Figure 14, respectively. That is, the internal operation of these entities may be as shown in Figure 12, and independently, the surrounding network topology may be that of Figure 14.

[0121] 15 depicts an OTT connection 550 abstractly to show communication between the host computer 510 and the UE 530 via the base station 520, but does not explicitly reference any intermediate devices or show the exact routing of messages through these devices. The network infrastructure may make routing decisions that may be configured to be hidden from the UE 530, or from the service provider operating the host computer 510, or both. The network infrastructure may further decide to dynamically change the routing (e.g., based on load balancing considerations or network reconfiguration) while the OTT connection 550 is active.

[0122] The wireless connection 570 between the UE 530 and the base station 520 follows the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of the OTT service provided to the UE 530 using the OTT connection 550 of which the wireless connection 570 forms the final segment. More precisely, the teachings of these embodiments can improve the availability and reliability of the service, thereby providing benefits such as reduced user latency and improved responsiveness.

[0123] Measurement procedures may be provided for the purpose of monitoring data rates, delay times (latency), and other factors that one or more embodiments improve. Additionally, there may be optional network functionality to reconfigure the OTT connection 550 between the host computer 510 and the UE 530 in response to variations in the measurement results. The measurement procedures and / or network functionality to reconfigure the OTT connection 550 may be implemented in the software 511 and hardware 515 of the host computer 510, or in the software 531 and hardware 535 of the UE 530, or both. In an embodiment, sensors (not shown) may be deployed in or associated with the communication devices through which the OTT connection 550 passes, and the sensors may participate in the measurement procedures by providing values ​​of the monitored quantities exemplified above, or by providing values ​​of other physical quantities from which the software 511, 531 can calculate or estimate the monitored quantities. The reconfiguration of the OTT connection 550 may include message formats, retransmission settings, preferred routing, etc., and the reconfiguration need not affect the base station 520 and may be unknown or imperceptible to the base station 520. Such procedures and functionality are known in the art and may be practiced. In certain embodiments, the measurements may include proprietary UE signaling to facilitate measurements of host computer 510 throughput, propagation times, delay times, etc. The measurements may be performed by having messages sent using OTT connection 550, particularly empty or "dummy" messages, while software 511 and 531 monitor propagation times, errors, etc.

[0124] FIG. 16 is a flow chart illustrating a method implemented in a communication system according to one embodiment. The communication system includes a host computer, a base station, and a UE as described with reference to FIG. 14 and FIG. 15. To simplify the disclosure, only the figures that refer to FIG. 16 are included in this section. In step 1310, the host computer provides user data. In sub-step 1311 of step 1310 (which may be optional), the host computer provides the user data by executing a host application. In step 1320, the host computer initiates a transmission carrying the user data to the UE. In step 1330 (which may be optional), the base station transmits the user data carried in the host computer initiated transmission to the UE according to the teachings of the embodiments described throughout this disclosure. In step 1340, the UE executes a client application associated with the host application executed by the host computer.

[0125] FIG. 17 is a flow chart illustrating a method implemented in a communication system according to one embodiment. The communication system includes a host computer, a base station, and a UE as described with reference to FIG. 14 and FIG. 15. To simplify the disclosure, only drawing references to FIG. 14 are included in this section. In step 1410 of the method, the host computer provides user data. In an optional sub-step (not shown), the host computer provides the user data by executing a host application. In step 1420, the host computer initiates a transmission carrying the user data to the UE. The transmission may be passed via a base station according to the teachings of the embodiments described throughout this disclosure. In step 1430 (which may be optional), the UE receives the user data carried in the transmission.

[0126] FIG. 18 is a flow chart illustrating a method implemented in a communication system according to one embodiment. The communication system includes a host computer, a base station, and a UE as described with reference to FIG. 14 and FIG. 15. To simplify the disclosure, only drawing references to FIG. 15 are included in this section. In step 1510 (which may be optional), the UE receives input data provided by the host computer. Additionally or alternatively, in step 1520, the UE provides user data. In sub-step 1521 (which may be optional) of step 1520, the UE provides the user data by executing a client application. In sub-step 1511 (which may be optional) of step 1510, the UE executes a client application that provides user data in response to the received input data provided by the host computer. In providing the user data, the executed client application may further take into account user input received from a user. Regardless of the particular manner in which the user data is provided, the UE initiates transmission of the user data to the host computer in sub-step 1530 (which may be optional). In step 1540 of the method, the host computer receives user data transmitted from the UE according to the teachings of the embodiments described throughout this disclosure.

[0127] FIG. 19 is a flow chart illustrating a method implemented in a communication system according to one embodiment. The communication system includes a host computer, a base station, and a UE as described with reference to FIG. 14 and FIG. 15. To simplify the disclosure, only the figures that refer to FIG. 16 are included in this section. In step 1610 (which may be optional), the base station receives user data from the UE according to the teachings of the embodiments described throughout this disclosure. In step 1620, the base station initiates transmission of the received user data to the host computer. In step 1630 (which may be optional), the host computer receives the user data carried in the transmission initiated by the base station.

[0128] Any suitable step, method, feature, function, or benefit disclosed herein may be performed via one or more functional units or modules of one or more virtual devices. Each virtual device may comprise several of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessors or microcontrollers, as well as digital signal processors (DSPs), other digital hardware, which may include dedicated digital logic.

[0129] 20 illustrates an exemplary virtual wireless device configuration 1700. The wireless device 1700 includes an acquisition module 1710 including instructions for obtaining a configuration for a demodulation reference signal (DMRS), the DMRS including a pattern using common resource elements of at least two of a plurality of radio access technologies. The wireless device 1700 further includes a transmission / reception module including instructions for multiplexing or demultiplexing transmissions or receptions based on the obtained demodulation reference signal. The wireless device 1700 may optionally include other program modules including instructions for performing any one of the methods described herein in association with the wireless device or UE.

[0130] An exemplary virtual network device 1800 is illustrated in FIG. 21. The network node 1800 comprises a determining module 1810 comprising instructions for determining a configuration for a demodulation reference signal (DMRS), the DMRS comprising a pattern of using common resource elements of at least two of a plurality of radio access technologies. The network node 1800 further comprises a transceiving module including instructions for multiplexing or demultiplexing transmission or reception based on the determined demodulation reference signal. The network node 1800 may optionally include other program modules comprising instructions for performing any one of the methods described herein with respect to a network node or base station.

[0131] The processing circuitry of the described apparatus may be configured to execute program code stored in memory, which may include one or more types of memory, such as read-only memory (ROM), random access memory (RAM), cache memory, flash memory devices, optical storage devices, etc. The program code stored in the memory includes program instructions for implementing one or more telecommunications and / or data communication protocols, as well as instructions for implementing one or more of the techniques described herein. In some embodiments, the processing circuitry may be used to cause each functional unit to perform a function corresponding to the respective functional unit in accordance with one or more embodiments of the present disclosure.

[0132] The term unit may have its conventional meaning in the field of electronic equipment, electrical devices, and / or electronic devices, and may include, for example, electrical and / or electronic circuits, devices, modules, processors, memories, logic solid state and / or discrete devices, computer programs or instructions for performing respective tasks, procedures, calculations, output, and / or display functions, etc., as described herein.

[0133] In some embodiments, a computer program, computer program product, or computer readable storage medium includes instructions that, when executed on a computer, perform any of the embodiments disclosed herein. In a further example, the instructions are carried on a signal or carrier and are executable on a computer and, when executed, perform any of the embodiments disclosed herein.

[0134] Further examples to illustrate one or more embodiments disclosed herein include: A method performed by a wireless device operating in a communication system, the communication system comprising a wireless spectrum shared by a plurality of radio access technologies, the method comprising: obtaining a configuration for a demodulation reference signal DMRS, the DMRS comprising a pattern using common resource elements of at least two of the plurality of radio access technologies; and transmitting and receiving a data transmission based on the resulting demodulated reference signal.

[0135] Example 2: The method of example 1, wherein the DMRS is configured for the first radio access technology and is orthogonal or quasi-orthogonal to the DMRSs configured for one or more of the multiple radio access technologies.

[0136] (Example 3) The method of Example 2, wherein the DMRS has at least partially co-scheduled radio resource elements for another one of a plurality of radio access technologies, is derived by code domain multiplexing (CDM), and includes a sequence that uses the same DMRS sequence as the DMRS for other users.

[0137] Example 4. The method of example 3, wherein the DMRS includes a time-domain orthogonal cover code (OCC) of length 4 for groups of four resource elements or length 2 for groups of two resource elements.

[0138] Example 5 The method of Example 4, further comprising: Either an OCC of length 2 is applied to one of the CDM groups, where each CDM group corresponds to two unique antenna ports, or an OCC of length 4 is applied to one of the CDM groups, where each CDM group corresponds to four unique antenna ports.

[0139] (Example 6) The method according to any one of the preceding examples, further comprising obtaining an antenna port indication.

[0140] (Example 7) The method described in Example 6, wherein the antenna port indication includes indicating whether other ports in the same CDM group are scheduled and / or the number of CDM groups for which physical downlink shared channel data is not scheduled.

[0141] (Example 8) The method according to any one of the previous examples, wherein the CDM corresponds to an OCC of length 4 that depends on subcarrier and / or physical resource block index.

[0142] (Example 9) A method according to any one of the preceding examples, further comprising acquiring a second DMRS configuration, the acquired DMRS configuration being the first DMRS configuration, the second DMRS being configured for specific resource elements from the DMRS and cell-specific reference signal configured for any one of the other radio access technologies.

[0143] Example 10: The method of embodiment 9, further comprising receiving an indication to select between the first DMRS configuration and the second DMRS configuration.

[0144] (Example 11) The method according to any one of the preceding examples, wherein the DMRS configuration is for uplink multi-user multiple-input multiple-output (MU-MIMO).

[0145] Example 12: A method performed by a network node of a communication system, the communication system comprising a radio spectrum shared by a plurality of radio access technologies, the method comprising: determining a configuration for a demodulation reference signal (DMRS), the DMRS including a pattern using common resource elements of at least two of a plurality of radio access technologies; and receiving or transmitting a data transmission based on the determined demodulation reference signal.

[0146] Example 13 The method of Example 12, further comprising: The method includes configuring a wireless device with the determined DMRS.

[0147] (Example 14) The method of Example 12 or 13, wherein the DMRS is configured for a first radio access technology and is orthogonal or quasi-orthogonal to the DMRS configured for one or more of the multiple radio access technologies.

[0148] (Example 15) The method of any one of Examples 12 to 14, wherein the DMRS is a co-scheduled radio resource element for another one of a plurality of radio access technologies, is derived by code domain multiplexing (CDM), and has a sequence that uses the same DMRS sequence as the DMRS for other users.

[0149] (Example 16) The method of example 15, wherein the DMRS has a time-domain orthogonal cover code (OCC) of length 4 for groups of 4 resource elements or length 2 for groups of 2 resource elements.

[0150] Example 17 The method of Example 16, further comprising: The OCC of length 2 is applied to one of the CDM groups, with each CDM group corresponding to two unique antenna ports; and An OCC of length 4 is applied to one of the CDM groups, where each CDM group corresponds to four unique antenna ports. Either of the methods.

[0151] (Example 18) The method of any one of Examples 12 to 17, further comprising transmitting an antenna port indication to the wireless device.

[0152] (Example 19) The method described in Example 18, wherein the antenna port indication includes indicating whether other ports in the same CDM group are scheduled and / or the number of CDM groups for which physical downlink shared channel data is not scheduled.

[0153] (Example 20) The method according to any one of Examples 12 to 19, wherein the CDM corresponds to an OCC of length 4 dependent on a subcarrier and / or physical resource block index.

[0154] (Example 21) The method according to any one of Examples 12 to 20, wherein the determined DMRS configuration is a first DMRS configuration, and further includes determining a second DMRS configuration, the second DMRS being configured for resource elements specific from the DMRS and cell-specific reference signal configured for any one of the other radio access technologies.

[0155] (Example 22) The method of Example 21, further comprising: transmitting an indication to the wireless device to select between the first DMRS configuration and the second DMRS configuration.

[0156] (Example 23) The method according to any one of Examples 12 to 22, wherein the DMRS configuration is for uplink multi-user multiple-input multiple-output (MU-MIMO).

[0157] Example 24: A wireless device / user equipment includes a processing circuit, a transceiver circuit, a memory, and a power supply circuit configured to provide power to the wireless device, the processing circuit comprising: - obtaining a configuration for a demodulation reference signal (DMRS), the DMRS comprising a pattern using common resource elements of at least two of the plurality of radio access technologies; - receiving or transmitting a data transmission based on the obtained demodulation reference signal; The wireless device / user equipment is configured to:

[0158] (Example 25) The wireless device of Example 24, wherein the processing circuit is further configured to perform any of the steps of Examples 1 to 11.

[0159] Example 26: A network node / base station including a processing circuit, a transceiver circuit, and a power supply circuit configured to provide power to the network node, the processing circuit comprising: determining a configuration for a demodulation reference signal (DMRS), the DMRS including a pattern using common resource elements of at least two of the multiple radio access technologies; - receiving or transmitting a data transmission based on the determined demodulation reference signal; A network node / base station configured to:

[0160] (Example 27) The network node of Example 26, wherein the processing circuitry is further configured to perform any of the steps of Examples 12 to 23.

[0161] (Example 28) A communication system including a host computer, a processing circuit configured to provide user data; a communication interface configured to transfer user data to a cellular network for transmission to a user equipment (wireless device); A communication system in which the cellular network supports multi-user multiple-input multiple-output (MIMO) communication and the communication system comprises a radio spectrum shared by multiple radio access technologies.

[0162] (Example 29) The communication system of Example 28, further comprising a network node.

[0163] (Example 30) The communication system of Example 28 or 29, further including a wireless device, the wireless device configured to communicate with the base station.

[0164] (Example 31) The communication system according to any one of Examples 28 to 30, processing circuitry of the host computer configured to execute a host application and thereby provide user data; A communication system, wherein the wireless device comprises a processing circuit configured to execute a client application associated with a host application.

[0165] Example 32 A method implemented in a communication system including a host computer, a non-terrestrial network including a communication satellite, and a network node, the network node being one of a terrestrial base station, a satellite base station or satellite gateway, and a user equipment (wireless device), the method comprising: providing user data at the host computer; A method comprising: initiating, in a host computer, a transmission carrying user data to a wireless device through a cellular network including a network node; and the network node performing the steps of any one of Examples 12 to 23.

[0166] (Example 33) The method of Example 32, further comprising transmitting user data at the base station.

[0167] (Example 34) The method described in Example 32 or 33, wherein the user data is provided at the host computer by executing a host application, and the method further includes executing, at the wireless device, a client application associated with the host application.

[0168] (Example 35) A user equipment (UE) configured to communicate with a base station, the UE comprising a radio interface and a processing circuit configured to perform any one of Examples 1 to 11.

[0169] Example 36. A computer program comprising instructions which, when executed on a computer or processing circuit, cause the computer or processing circuit to perform any one of the methods of Examples 1-11 or Examples 12-23.

[0170] (Example 37) A computer program product, memory, or carrier comprising computer program instructions according to Example 36.

Claims

1. A method performed by a wireless device (110, 200) operating in a communication system, the communication system including use of a wireless spectrum shared by multiple radio access technologies, the method comprising: Obtaining (600) a configuration for a demodulation reference signal (DMRS), the DMRS occupying resource elements identified by a pattern and using common resource elements of at least two of the plurality of radio access technologies; Obtaining (610) an antenna port indication; Transmitting or receiving a data transmission based on the obtained demodulation reference signal (630); Including, the DMRS is configured for a first radio access technology and is orthogonal or quasi-orthogonal to a DMRS configured for a different one of the plurality of radio access technologies; wherein the different one of the plurality of radio access technologies is comprised of a cell-specific reference signal (CRS); The antenna port indication includes indicating whether other ports in the same CDM group are scheduled.

2. 2. The method of claim 1, wherein the DMRS has at least partially co-scheduled radio resource elements for another one of the multiple radio access technologies, is derived by code domain multiplexing (CDM), and includes a sequence that uses the same DMRS sequence as a DMRS for another user.

3. 3. The method of claim 2, wherein the DMRS comprises a time-domain orthogonal cover code (OCC) of length 4 for groups of four resource elements or length 2 for groups of two resource elements.

4. An OCC of length 2 is applied to one of the CDM groups, each CDM group corresponding to two unique antenna ports; and A length-4 OCC is applied to one of the CDM groups, where each CDM group corresponds to four unique antenna ports. The method according to claim 3, wherein the

5. The method of claim 1 , wherein the indication comprises a number of CDM groups without physical downlink shared channel data transmission.

6. The method of claim 1 , wherein the CDM corresponds to a length-4 OCC that depends on subcarrier and / or physical resource block indices.

7. 7. The method of claim 1, wherein the obtained DMRS configuration is a first DMRS configuration, and the method further comprises obtaining a second DMRS configuration, the second DMRS configured for specific resource elements from a DMRS configured for any one of other radio access technologies and a cell-specific reference signal.

8. 8. The method of claim 7, further comprising receiving an indication to select between the first DMRS configuration and the second DMRS configuration (620).

9. The method of claim 1 , wherein the DMRS configuration is for uplink multi-user multiple-input multiple-output (MU-MIMO).

10. A method performed by a network node (160) of a communication system, the communication system including use of a radio spectrum shared by multiple radio access technologies, the method comprising the steps of: determining (700) a configuration of a demodulation reference signal (DMRS), the DMRS occupying resource elements identified by a pattern and using common resource elements of at least two of the plurality of radio access technologies; Configuring (710) a wireless device with the determined configuration for the DMRS; receiving or transmitting (720) a data transmission based on the determined configuration for the demodulation reference signal; transmitting (730) an antenna port indication to the wireless device; Including, the DMRS is configured for a first radio access technology and is orthogonal or quasi-orthogonal to a DMRS configured for a different one of the plurality of radio access technologies; wherein the different one of the plurality of radio access technologies is comprised of a cell-specific reference signal (CRS); The antenna port indication may be Indicating whether other ports in the same CDM group are scheduled; and the number of CDM groups without physical downlink shared channel data transmission; A method comprising at least one of the following:

11. the DMRS has co-scheduled radio resource elements for another one of the plurality of radio access technologies and is derived by Code Domain Multiplexing (CDM) and includes a sequence using the same DMRS sequence as a DMRS for another user; the DMRS includes a time-domain orthogonal cover code (OCC) of length 4 for groups of four resource elements or length 2 for groups of two resource elements; An OCC of length 2 is applied to one of the CDM groups, each CDM group corresponding to two unique antenna ports; and A length-4 OCC is applied to one of the CDM groups, where each CDM group corresponds to four unique antenna ports. Either of The method of claim 10.

12. The method according to claim 10 or 11, wherein the CDM corresponds to a length-4 OCC dependent on subcarrier and / or physical resource block index.

13. The determined DMRS configuration is a first DMRS configuration, and the method further includes determining a second DMRS configuration, the second DMRS being configured for resource elements specific from a DMRS configured for any one of the other radio access technologies and a cell-specific reference signal; 13. The method of claim 10, further comprising: transmitting an indication to a wireless device to select between the first DMRS configuration and the second DMRS configuration.

14. A wireless device (110, 200) comprising a processing circuit, a transceiver circuit, a memory, and a power supply circuit configured to provide power to said wireless device, said processing circuit comprising: obtaining a configuration for a demodulation reference signal (DMRS), the DMRS comprising a pattern using common resource elements of at least two of the plurality of radio access technologies; Get antenna port indication, receiving or transmitting a data transmission based on the obtained demodulation reference signal; It is configured as follows: the DMRS is configured for a first radio access technology and is orthogonal or quasi-orthogonal to a DMRS configured for a different one of the plurality of radio access technologies; wherein the different one of the plurality of radio access technologies is comprised of a cell-specific reference signal (CRS); The antenna port indication includes indicating whether other ports in the same CDM group are scheduled.

15. The wireless device of claim 14, wherein the processing circuitry is further configured to perform any one of the steps recited in any one of claims 2 to 9.

16. A network node (160) comprising a processing circuit, a transceiver circuit, and a power supply circuit configured to supply power to said network node, said processing circuit comprising: determining a configuration for a demodulation reference signal (DMRS), the DMRS including a pattern using common resource elements of at least two of the plurality of radio access technologies; configuring a wireless device with the determined configuration for the DMRS; receiving or transmitting a data transmission based on the determined demodulation reference signal; transmitting an antenna port indication to the wireless device; It is configured as follows: the DMRS is configured for a first radio access technology and is orthogonal or quasi-orthogonal to a DMRS configured for a different one of the plurality of radio access technologies; wherein the different one of the plurality of radio access technologies is comprised of a cell-specific reference signal (CRS); The antenna port indication may be Indicating whether other ports in the same CDM group are scheduled; and the number of CDM groups without physical downlink shared channel data transmission; A network node including at least one of:

17. 17. The network node of claim 16, wherein the processing circuitry is further configured to perform any one of the steps recited in any one of claims 11 to 13.

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