Integrated circuits for user equipment and base stations

Abstract

The present disclosure relates to an integrated circuit for controlling a user equipment for transmitting and / or receiving data to / from a base station. The integrated circuit includes a control circuit, receiving parameters defining a rule for assigning corresponding resources for carrying reference signals to ports, generating a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station, and receiving control information from the base station indicating a layer-to-port mapping combination in the set of layer-to-port mapping combinations to be applied to data transmission and / or reception, wherein, in the set of layer-to-port mapping combinations, a dual-symbol layer-to-port mapping combination for multiple layers includes a mapping combination with consecutive port numbers, at least one of which is duplicated in a subsequent mapping combination of the same multiple layers and consecutive indexes.

Description

[0001] This application is a divisional application of the invention patent application with the application date of August 11, 2017, application number: 201780093657.9, and invention name: "New Radio (NR) Demodulation Reference Signal (DMRS) Port Mapping and Related Signaling". Background Art 1. Technical Field

[0003] The present disclosure relates to the transmission and reception of data and / or reference signals in resources of a communication system.

[0004] 2. Description of Related Technology

[0005] Currently, the Third Generation Partnership Project (3 rd The 3GPP (3rd Generation Partnership Project) is working on the next release (Release 15) of the technical specifications for the next generation of cellular technology, also known as the fifth generation (5G). At the 71st meeting of the 3GPP Technical Specification Group (TSG) Radio Access Network (RAN) (March 2016, Gothenburg), the first 5G study project "Study of New Radio Access Technologies" was approved, involving RAN1, RAN2, RAN3 and RAN4, and is expected to become the Release 15 work item that defines the first 5G standard.

[0006] One goal of 5G NR is to provide a single technical framework that addresses all usage scenarios, requirements, and deployment scenarios defined in 3GPP TSG RAN TR 38.913v14.1.0 "Study on Scenarios and Requirements for Next Generation Access Technologies", Dec. 2016 (available at www.3gpp.org and incorporated herein by reference in its entirety), including at least enhanced Mobile Broadband (eMBB), Ultra-Reliable Low-Latency Communication (URLLC), and massive Machine Type Communication (mMTC). For example, eMBB deployment scenarios may include indoor hotspots, dense urban, rural, urban macro, and high-speed; URLLC deployment scenarios may include industrial control systems, mobile healthcare (remote monitoring, diagnosis, and treatment), vehicle real-time control, and smart grid wide-area monitoring systems; mMTC may include scenarios with a large number of devices with non-time-critical data transmission, such as smart wearable devices and sensor networks.

[0007] Another goal is forward compatibility. Backward compatibility with Long Term Evolution (LTE) is not required, which facilitates completely new system designs and / or the introduction of new features.

[0008] As described in the NR study (3GPP TSG TR 38.801v2.0.0, “Study on New Radio Access Technology; Radio Access Architecture and Interfaces”, March 2017), the basic physical layer signal waveform will be based on orthogonal frequency division multiplexing (OFDM). For both downlink and uplink, waveforms based on cyclic prefix OFDM (CP-OFDM) are supported. Waveforms based on discrete Fourier transform (DFT) spread OFDM (DFT-S-OFDM) are also supported, which is complementary to the CP-OFDM waveform, at least for the eMBB uplink up to 40 GHz.

[0009] One of the design goals of NR is to find common waveforms for downlink, uplink, and sidelink as much as possible. It has been taken into account that for some uplink transmission situations, it may not be necessary to introduce DFT spreading. The term "downlink" refers to communication from a higher node to a lower node (e.g., from a base station to a relay node or to a UE, from a relay node to a UE, etc.). The term "uplink" refers to communication from a lower node to a higher node (e.g., from a UE to a relay node or to a base station, from a relay node to a base station, etc.). The term "sidelink" refers to communication between nodes of the same level (e.g., between two UEs, or between two relay nodes, or between two base stations).

[0010] The term spatial layer (or layer) refers to one of the different streams generated by spatial multiplexing. A layer can be described as a mapping of symbols to transmit antenna ports. Each layer is identified by a precoding vector of size equal to the number of transmit antenna ports and can be associated with a radiation pattern. The rank of transmission is the number of layers transmitted. A codeword is an independently encoded block of data corresponding to a single transport block (TB) transmitted from the medium access control (MAC) layer in the transmitting unit to the physical layer and protected by a cyclic redundancy check (CRC). Typically, one layer is assigned per transmission time (TTI) interval, which corresponds to a subframe in LTE. However, in NR, there may be different TTIs, depending on URLLC or eMBB. Specifically, in NR, a TTI can be a slot, a mini slot, or a subframe. For layers, ranks, and codewords, see also Section 11.2.2.2 of S. Sesia, I. Toufik and M, Baker, LTE: UMTS Long Term Evolution, Second Edition, incorporated herein by reference.

[0011] A reference signal pattern (RS) is transmitted from an antenna port (or ports) of a base station. A port may transmit as a single physical transmit antenna or as a combination of multiple physical antenna elements. In either case, the signal transmitted from each antenna port is not designed to be further deconstructed by the UE receiving unit: from the UE's perspective, the transmitted RS corresponding to a given antenna port defines the antenna port and enables the UE to derive a channel estimate for all data transmitted on that antenna port, regardless of whether it represents a single radio channel from one physical antenna or a composite channel from multiple physical antenna elements that together make up the antenna port. Regarding ports, see also Section 8.2 of S. Sesia, I. Toufik and M, Baker, LTE: Long Term Evolution for UMTS, Second Edition, incorporated herein by reference.

[0012] In LTE, the base station schedules the data transmission and reception of the UE through the Physical Downlink Control Channel (PDCCH), which carries a message called Downlink Control Information (DCI), which includes resource allocation and other control information for the UE or a group of UEs. Typically, several PDCCHs can be transmitted in one subframe.

[0013] The required content of the control channel messages depends on the system deployment and the UE configuration. For example, if the infrastructure does not support MIMO, or if the UE is configured in a transmission mode that does not involve MIMO, then no signaling is required to notify the parameters required for MIMO-only transmission. In order to minimize the signaling overhead, it is therefore desirable to have several different message formats available, each containing the minimum payload required for a specific scenario. On the other hand, in order to avoid overly complex implementation and testing, it is desirable not to specify too many formats. The set of DCI message formats specified in LTE is listed below:

[0014] Please refer to the above mentioned technical standards or Chapter 9.3.5 of LTE - UMTS Long Term Evolution - From Theory to Practice edited by Stefanie Sesia, Issam Toufik, Matthew Baker, which is incorporated herein by reference.

[0015] - Format 0: DCI format 0 is used to transmit resource grants for PUSCH transmitted using a single antenna port in uplink transmission mode 1 or 2.

[0016] - Format 1: DCI format 1 is used to transmit resource assignments for single codeword PDSCH transmissions (downlink transmission modes 1, 2 and 7).

[0017] - Format 1A: DCI format 1A is used for compact signaling of resource allocation for single codeword PDSCH transmissions and for dispatching dedicated preamble signatures to mobile terminals for contention-free random access (for all transmission modes).

[0018] - Format 1B: DCI format 1B is used for compact signaling of resource assignments for PDSCH transmissions using closed-loop precoding transmissions of rank 1 (downlink transmission mode 6). The information transmitted is the same as in format 1A, but with the addition of an indicator of the precoding vector applied for the PDSCH transmission.

[0019] -Format 1C: DCI format 1C is used for very compact transmission of PDSCH assignments. When format 1C is used, PDSCH transmissions are restricted to use QPSK modulation. This is used, for example, for signaling paging messages and broadcasting system information messages.

[0020] -Format 1D: DCI format 1D is used for compact signaling of resource assignments for PDSCH transmissions using multi-user MIMO. The information transmitted is the same as in format 1B, but instead of one bit for the precoding vector indicator, there is a single bit to indicate whether a power offset is applied to the data symbol. This feature is needed to show whether the transmission power is shared between two UEs. Future versions of LTE may extend this feature to the case where power is shared between a larger number of UEs.

[0021] - Format 2: DCI format 2 is used for transmitting resource allocations of PDSCH for closed-loop MIMO operation (transmission mode 4).

[0022] -Format 2A: DCI format 2A is used to transmit resource assignments for PDSCH for open-loop MIMO operation. The information transmitted is the same as that of format 2, except that if the eNodeB (the name for base station in LTE) has two transmit antenna ports, there is no precoding information, and for four antenna ports, two bits are used to indicate the transmission rank (transmission mode 3).

[0023] - Format 2B: Introduced in Release 9, resource allocation for PDSCH transmission with dual-layer beamforming (transmission mode 8).

[0024] - Format 2C: Introduced in Release 10, PDSCH resource allocation for transmission of up to 8 layers for closed-loop single-user or multi-user MIMO operation (transmission mode 9).

[0025] - Format 2D: introduced in Release 11 for up to 8-layer transmission; mainly used for COMP (Cooperative Multipoint) (Transmission Mode 10)

[0026] - Format 3 and 3A: DCI formats 3 and 3A are used to transmit power control commands for PUCCH and PUSCH with 2-bit or 1-bit power adjustment, respectively. These DCI formats contain individual power control commands for a group of UEs.

[0027] - Format 4: DCI format 4 is used for scheduling of PUSCH using closed-loop spatial multiplexing transmission in uplink transmission mode 2.

[0028] The search space indicates a set of CCE locations where the UE can find its PDCCH. Each PDCCH carries a DCI and is identified by an RNTI (Radio Network Temporary Identity) implicitly encoded in the CRC check bits (CRC attachment) of the DCI. The UE monitors the CCEs of the configured (multiple) search spaces by blind decoding and checking the CRC. The search spaces can be common search spaces and UE-specific search spaces. The UE needs to monitor both common and UE-specific search spaces, which can overlap. The common search space carries DCI that is common to all UEs, such as system information (using SI-RNTI), paging (P-RNTI), PRACH response (RA-RNTI) or UL TPC commands (TPC-PUCCH / PUSCH-RNTI). The UE-specific search space can carry DCI for UE-specific allocations, using the UE's assigned C-RNTI, semi-persistent scheduling (SPS C-RNTI) or initial allocation (temporary C-RNTI).

[0029] Therefore, DCI specifies the resources for the UE to receive or send data, including the transmission and reception configuration. Summary of the invention

[0030] A non-limiting and exemplary embodiment facilitates supporting flexible layer-to-port mapping and flexible configuration of single-symbol or dual-symbol DMRS within various front-loaded DMRS configurations while maintaining reasonable signaling overhead.

[0031] In one general aspect, the technology disclosed herein is characterized by a user equipment for sending data to a base station and / or receiving data from a base station using multiple antennas in a communication system, the user equipment including a circuit that receives parameters defining a rule for assigning corresponding resources for carrying reference signals to ports, generates a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station, and receives control information from the base station indicating a layer-to-port mapping combination in the set of layer-to-port mapping combinations to be applied for data transmission and / or reception.

[0032] In another general aspect, the technology disclosed herein is characterized by an integrated circuit for controlling a user equipment for sending and / or receiving data to / from a base station, including a control circuit, receiving parameters defining a rule for assigning corresponding resources for carrying reference signals to ports, generating a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station, and receiving control information from the base station indicating a layer-to-port mapping combination in the set of layer-to-port mapping combinations to be applied for data transmission and / or reception, wherein, in the set of layer-to-port mapping combinations, dual-symbol layer-to-port mapping combinations for multiple layers include mapping combinations with consecutive port numbers, at least one of which is duplicated in a subsequent mapping combination of the same multiple layers with consecutive indexes.

[0033] In yet another general aspect, the technology disclosed herein is characterized by an integrated circuit for controlling a base station for receiving and / or transmitting data from / to a user equipment, comprising a control circuit, sending parameters defining a rule for assigning corresponding resources for carrying reference signals to ports, generating a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station, and sending control information to the user equipment indicating a layer-to-port mapping combination in the set of layer-to-port mapping combinations to be applied for data reception and / or transmission, wherein, in the set of layer-to-port mapping combinations, dual-symbol layer-to-port mapping combinations for multiple layers include mapping combinations with consecutive port numbers, at least one of which is duplicated in a subsequent mapping combination of the same multiple layers with consecutive indexes.

[0034] It should be noted that the general or specific embodiments may be implemented as a system, a method, an integrated circuit, a computer program, a storage medium, or any selective combination thereof.

[0035] Other benefits and advantages of the disclosed embodiments will become apparent from the specification and drawings. Benefits and / or advantages may be obtained individually from various embodiments and features of the specification and drawings, and do not require all to be provided to obtain one or more of these benefits and / or advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figures 1A to 1D is a schematic diagram of a pre-demodulation reference signal (DMRS) configuration type.

[0037] Figure 2 is a block diagram showing the structure of a transmitting device and a receiving device.

[0038] Figure 3 is a block diagram showing a framework for DMRS port indexing, layer-to-port mapping, and indication of single-symbol or dual-symbol DMRS.

[0039] Figure 4A and Figure 4B is a diagram of exemplary port numbering for exemplary single-symbol DMRS configuration types.

[0040] Figure 5A and Figure 5B is a diagram of exemplary port numbering for exemplary dual-symbol DMRS configuration types.

[0041] Figure 6 is a block diagram showing circuitry of a user equipment.

[0042] Figure 7 is a diagram showing a downlink demodulation reference signal (DMRS) having 8 orthogonal ports. DETAILED DESCRIPTION

[0043] In the 3rd Generation Partnership Project New Radio (3 rd In the 3rd Generation Partnership Project NewRadio (3GPP NR), reference signals are redesigned to meet a wide range of requirements and use cases. The demodulation reference signal (DMRS) used for channel estimation purposes is also designed to have a unified structure for both uplink and downlink using a cyclic prefix orthogonal frequency division multiplexing (CP-OFDM) waveform. The present disclosure relates to pre-DMRS port mapping (at the beginning of the data channel) and related signaling aspects. It has been agreed to support two configurations of pre-DMRS (with different multiplexing schemes for orthogonal DMRS ports), and each configuration has the flexibility to use 1-symbol or 2-symbol DMRS. In current LTE, for orthogonal DMRS ports, there is a fixed configuration with a single category of multiplexing schemes, and a fairly strict layer-to-port mapping is allowed. However, in NR, it is expected that it will have flexible layer-to-port mapping to take advantage of the benefits of different multiplexing schemes for orthogonal DMRS ports. In the present disclosure, we provide a framework to flexibly configure port indexes, generate layer-to-port mappings, and how to indicate 1-symbol or 2-symbol DMRS and table indexes for each configuration.

[0044] The present disclosure relates to NR technology. For ongoing work items on NR access technology, see 3GPP TSGRAN Meeting #75, RP-171485 by NTT DoCoMo, “Revised WID on New Radio Access Technology”, June 5-8, 2017. More specifically, it handles the pre-DMRS aspects for both downlink and uplink using CP-OFDM waveforms. In the Chairman's Notes from RAN1 NR #2 (RAN1 Chairman Notes: RAN1 NR Ad-Hoc #2, incorporated herein by reference), all the latest DMRS-related protocols are obtained, and the present disclosure relates to some aspects that have not been discussed or are left for further discussion. The present disclosure provides a framework for flexible DMRS layer-to-port mapping and signaling of 1-symbol or 2-symbol DMRS within each pre-DMRS configuration.

[0045] As mentioned above, in 3GPP NR, the Demodulation Reference Signal (DMRS) is redesigned for both downlink and uplink.

[0046] According to the latest protocol, the pre-DMRS in the downlink and uplink using the CP-OFDM waveform supports two configurations, such as Figures 1A to 1D As shown. If single-symbol DMRS is used, the preamble reference signal is allocated to the first data symbol adjacent to the signaling part of the TTI (the signaling part consists of, for example, two symbols), that is, if double-symbol DMRS is used, it is allocated to the first two data symbols. Specifically, the following relevant protocols related to NR DMRS are proposed in 3GPP TSG RAN WG1Meeting NR Ad-Hoc#2, R1-1711784Agenda item: 5.1.2.4.3, MediaTek et al., “WF on DMRS Design”, Qingdao, China, June 27–30, 2017, incorporated herein by reference, and updated and agreed in the Chairman's Note incorporated herein by reference (available at www.3gpp.org).

[0047] The working assumptions for DM-RS in RAN1#89 were updated and the following agreement was reached for CP-OFDM: For DL / UL, the UE is configured with a DMRS mode by higher layer signaling, which comes from either pre-DMRS configuration type 1 or pre-DMRS configuration type 2.

[0048] Figure 1A to Figure 1BEach shows an exemplary grid corresponding to a time slot of 14 symbols and 12 subcarriers. The first two symbols on the left side of each figure correspond to the signaling portion of the time slot. The physical downlink control channel (PDCCH) is signaled in the signaling portion. In LTE, a subframe always includes two time slots. However, in general communication systems, a subframe may correspond to one time slot or include more than two time slots. In addition, the present disclosure is not limited to time slots with 14 symbols and 12 subcarriers.

[0049] The first pre-DMRS configuration corresponding to configuration type 1 is as follows Figure 1A and 1B This configuration is designed to support up to eight orthogonal ports for single-user multiple input multiple output (SU-MIMO) or multi-user multiple input multiple output (MU-MIMO). If single-symbol DMRS is used, the first configuration supports up to four orthogonal ports, such as Figure 1A Specifically, two comb teeth and two cyclic shifts (CS) can be combined to form up to four component sets, and the corresponding resulting component sets can be respectively assigned to up to four ports. If dual-symbol DMRS is used, as shown in FIG. Figure 1B As shown, the two combs and two cyclic shifts can be further combined with two time division orthogonal cover codes (TD-OCC), specifically Walsh-Hadamard TD-OCC, ({1, 1} and {1, -1}), and up to eight orthogonal ports can be supported. However, in the case of double-symbol DMRS, up to 4 ports can also be scheduled without using both {1, 1} and {1, -1}.

[0050] The second pre-DMRS configuration corresponding to configuration type 2 is as follows Figure 1C and Figure 1D As shown. This configuration provides support for up to twelve orthogonal ports for SU-MIMO or MU-MIMO. Specifically, two (Walsh-Hadamard) frequency division orthogonal cover codes (FD-OCC) are applied to adjacent Re (resource elements) in the frequency domain, generating six component sets. Figure 1C and Figure 1DIt can be seen that the adjacent RE pairs with twelve subcarriers are divided into three frequency division multiplexing (FDM) groups. Therefore, the six component sets come from two FD-OCCs (both {1, 1} and {1, -1}) applied to the three FDM groups respectively. Figure 1C ), the resulting six corresponding component sets can be assigned to up to six orthogonal ports. In the case of dual-symbol DMRS, these six component sets can be further combined with two TD-OCCs to support up to twelve orthogonal ports ( Figure 1D ).

[0051] As above reference Figures 1A to 1D As described above, comb teeth, cyclic shift, FD-OCC, FDM and TD-OCC constitute resource components of reference signals (specifically pre-DMRS). These resource components are combined according to the first or second pre-DMRS configuration, and the resulting component sets are respectively assigned to orthogonal ports. However, even for low rank, the use of dual-symbol DMRS should be possible. Not all component sets supported by a specific configuration in the case of single-symbol or dual-symbol DMRS need to be used for port assignment. Specifically, in the case of dual symbols, up to 6 ports can also be scheduled using both {1, 1} and {1, -1}.

[0052] From the perspective of user equipment (UE), DMRS ports multiplexed by frequency-domain code division multiplexing (CDM) are quasi-co-located.

[0053] Whether the pre-DMRS configuration types of UEs for UL and DL are different remains to be further studied. In addition, if there are significant complexity / performance issues involved in the above protocols, down-selection can still be discussed.

[0054] In addition, the following agreement was reached on the use of 2-symbol DMRS in the low-rank case (for these agreements, see 3GPP TSG RAN WG1 Meeting NR Ad-Hoc #2R1-1711771, Agenda Item: 5.1.2.4.3, LG Electronics, ZTE, "WF on signaling DMRS configuration", Qingdao, China, 27-30 June 27-30, 2017, incorporated herein by reference): When the number of DMRS ports allocated to the UE is equal to or less than N, the number of leading DMRS symbols can be 1 or 2, for configuration 1, N is 4, and for configuration 2, N is 6. The details of determining whether to use single-symbol DMRS or double-symbol DMRS remain to be further studied.

[0055] Current LTE DMRS configuration

[0056] The DMRS configuration in the above NR is different from LTE. In LTE, the downlink mainly uses a single configuration using code division multiplexing in frequency and time using Walsh-Hadamard orthogonal cover codes to support Figure 7 Up to 8 orthogonal ports / layer shown. Figure 7 The configuration of and more details on DMRS configuration in LTE can be found in Section 29.1.1 of S. Sesia, I. Toufik and M. Baker, LTE: Long Term Evolution for UMTS, 2nd Edition, incorporated herein by reference.

[0057] The layer-to-port mapping table in the current LTE is taken from 3GPP TS 36.212, V14.3.0 (Table 5.3.3.1.5C-2), as shown in Table 1 below:

[0058]

[0059]

[0060] Table 1 (Multiple) antenna ports, scrambling identifier (SCID) and layer number indication

[0061] In current LTE, up to eight orthogonal DMRS ports for downlink are supported, which mainly use a single category of multiplexing scheme, namely OCC in time / frequency. Therefore, any port combination can be used to map layers without affecting the performance of a given scenario. In addition, for a given number of layers, the use of resources (DMRS overhead) is the same for any port combination.

[0062] In addition, current LTE has limited support for MU-MIMO. In addition, fixed DMRS configuration is supported; therefore, dynamic configuration does not require additional signaling.

[0063] Furthermore, it can be seen from Table 1 that the combinations allowed for layer-to-port mapping are very limited. In current LTE, a bitmap of length 4 is defined to signal the layer-to-port mapping for a given user: The layer-to-port mapping supports a minimum number of port combinations. Specifically, for up to two layers, the mapped port indices are consecutive and non-overlapping. For three to eight layers, the indices are consecutive, non-overlapping, and start from index 0 as a fixed starting point. The mapping is limited to one port combination.

[0064] DMRS requirements for NR

[0065] This may not be sufficient in NR due to the issues described in the next section. To the best of our knowledge, no other solution is available other than specifically dealing with the issues related to DMRS port mapping and the related signaling in NR, mainly because the current agreement is very recent.

[0066] In NR, DMRS configuration is required to support multiple scenarios, including uplink, downlink, different carrier frequencies, and low latency. The mapping of user layers to orthogonal DMRS ports is expected to be flexible for the following reasons. First, different ports may correspond to different types of multiplexing schemes, and their performance may vary in different scenarios. Second, if the layer-to-port mapping is performed in different ways, the usage of resources (DMRS overhead) may be different for a given number of layers. Third, support for MU-MIMO is expected to be improved compared to current LTE. For each pre-DMRS configuration, it is expected to flexibly configure single-symbol or dual-symbol DMRS.

[0067] In order to support flexible layer-to-port mapping for different scenarios, it is necessary to allow more port combinations, resulting in increased signaling overhead. In addition, selecting 1-symbol or 2-symbol DMRS for a given pre-DMRS configuration type will further increase the signaling overhead.

[0068] Based on these requirements, there is a need to support flexible configuration of single-symbol or multi-symbol DMRS within different pre-DMRS configurations and flexible layer-to-port mapping while allowing reasonable signaling overhead.

[0069] Description of Embodiments

[0070] The present disclosure helps to support flexible configuration of single-symbol or multi-symbol DMRS within different pre-DMRS configurations and flexible layer-to-port mapping while allowing reasonable signaling overhead.

[0071] In an exemplary embodiment, if Figure 2 As shown, the present disclosure provides a user equipment 210 for sending and / or receiving data to / from a base station 260 using multiple antennas in a communication system. The user equipment may correspond to a user equipment (UE) as it is usually named in LTE and NR. Typically, a radio channel is used for sending and / or receiving. The user equipment includes a circuit 230, which is adapted to receive parameters for assigning resources of a reference signal to a port, generate a set of mapping combinations of layers to ports, and receive control information indicating one of these mapping combinations to be applied to data transmission and / or reception from the base station 260.

[0072] Specifically, circuit 230 receives parameters defining a rule for allocating corresponding resources for carrying reference signals to ports. The resources allocated to the ports typically include at least two resource components. For example, according to Figures 1A to 1D For the corresponding configurations shown, these resource components correspond to combs, cyclic shifts, FD-OCC, and FDM.

[0073] Based on the mapping known to the user equipment 210 and the base station 260, the circuit 230 of the user equipment 210 generates a set of layer-to-port mapping combinations, wherein the layer-to-port mapping combination specifies how the layers used by a specific user terminal such as the user equipment 210 for data transmission or reception are mapped to available ports in a given port configuration per TTI.

[0074] In addition, the circuit 230 of the user equipment 210 receives control information from the base station 260, which indicates a specific layer-to-port mapping combination from the set of layer-to-port mapping combinations to be applied to data transmission and / or reception for each TTI. That is, the indicated layer-to-port mapping combination defines the port to which the layer used for data transmission or reception by the user equipment 210 is mapped. Among them, TTI can be, for example, a time slot, a mini time slot or a subframe.

[0075] For example, control information indicating a layer-to-port mapping combination may be transmitted within a DCI on a PDCCH and is part of a scheduling configuration that notifies the terminal to apply this particular layer-to-port mapping combination to the transmission and / or reception of data. Typically, a DCI may be used for scheduling uplink or downlink data transmission (typically, both may also be scheduled). Upon receiving the DCI, the UE configures the layers and ports according to the received layer-to-port mapping combination and receives or sends data in the scheduled resources accordingly.

[0076] like Figure 2As shown, the user equipment 210 includes a transceiver unit 220, i.e., a transmitting unit and a receiving unit for transmitting and receiving radio waves through a wireless channel. The transceiver unit 220 applies the indicated layer-to-port mapping combination indicated by the control information received from the base station to perform data transmission and / or reception.

[0077] The structure of the circuit 230 of the user equipment 210 is as follows Figure 6 As shown. The circuit 230 of the user equipment includes a signaling information receiving unit 232 and a mapping generating unit 231. The signaling information receiving unit 232 receives parameters defining a rule for assigning corresponding resources for carrying reference signals to ports. The mapping generating unit 231 generates a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station. The signaling information receiving unit 232 also receives control information indicating a layer-to-port mapping combination in the set of layer-to-port mapping combinations to be applied to data transmission and / or reception from the base station 260. It should be noted that the transceiver unit 220 of the user equipment 210 receives radio waves sent by the base station 260 through a wireless channel. The circuit 230 of the user equipment receives demodulated data and / or control data from a lower layer.

[0078] Corresponding to the user equipment 210, the present disclosure also provides a base station 260 for receiving data from the user equipment and / or sending data to the user equipment in a communication system. The base station can be, for example, an eNodeB (eNB) or a similar entity in NR (currently referred to as a gNB). The present disclosure is also applicable to a relay node (either as a base station described herein or as a relay node processed by the user equipment described herein). The base station 260, or more specifically, a transceiver unit 270 included in the base station 260, includes multiple antennas that transmit or receive data. In addition, the base station 260 includes a circuit 280, which transmits parameters via the transceiver unit 270, which defines a rule for assigning corresponding resources for carrying reference signals to ports. The circuit 280 of the base station 260 also generates a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station. Therefore, the base station can perform scheduling of the UE, that is, assign resources to the UE for transmission or reception, and provide the UE with corresponding configurations to be applied to the transmission and reception parameters (such as modulation, coding, layer and port configurations, etc., as described above with respect to DCI). The base station may perform scheduling for one or more UEs. In addition, the circuit 280 of the base station 260 sends control information to the user equipment 210 via the transceiver unit 270, the control information indicating a layer-to-port mapping combination in a set of layer-to-port mapping combinations to be applied by the user equipment 210 for data reception and / or transmission. The control information may be similar to DCI. After sending control information for scheduling data transmission for the UE in the downlink, the base station will send data in the downlink with the allocated resources and using the layer-to-port combination. After sending control information for scheduling data transmission for the UE in the uplink, the base station will receive data from the UE in the uplink with the allocated resources and using the layer-to-port combination.

[0079] like Figure 2 As shown, the base station 260 includes a transceiver unit 270, that is, a transmitting unit and a receiving unit for transmitting and receiving radio waves through a wireless channel. The transceiver unit 270 performs reception and / or transmission of data transmitted and / or received by the user equipment 210, and the user equipment 210 applies the indicated layer-to-port mapping combination indicated by the control information received from the base station. The transceiver unit 270 includes multiple antennas of the base station.

[0080] For example, the circuit 280 of the base station 260 further configures parameters that define rules for assigning corresponding resources for carrying reference signals to ports. For example, the base station 260 uses the circuit 280 to configure parameters for defining rules for port assignment and sends the parameters to multiple user equipments.

[0081] In addition, for example, the circuit 280 of the base station 260 may also configure the control information to be applied to the user equipment 210 or multiple user equipments according to the corresponding layer number of the user equipment 210 or multiple user equipments. Therefore, the user equipment, for example, sends the corresponding control information to the corresponding user equipment.

[0082] For example, the rules for assigning corresponding resources of reference signals to ports (port assignment rules) also define port indexes, specifically port index / port number sequences. That is, for each port and the corresponding set of resource components assigned to a given port, the port number (index) is determined by the port index sequence. If such a port index sequence is defined, the mapping based on which the layer-to-port mapping combination is based can reference ports by their indexes.

[0083] Specifically, if the port dispatch rule defines a port index, the mapping can be specified, for example, as follows:

[0084] 1) The layers of each layer-to-port mapping combination are mapped to ports of consecutive indexes ("continuous mapping"). That is, in each layer-to-port mapping combination, there are no gaps between port indices.

[0085] 2) The index of the port to which each layer of the first configuration is mapped is less than the index of each port to which any layer of the second configuration is mapped, and the first configuration has a higher rank than the second configuration, the rank being the number of layers of the configuration ("higher rank priority"). That is, a user terminal with a higher rank (i.e., having more layers to be mapped to a port, such as at least two layers) is mapped "first", i.e., mapped to a port with a smaller port number than another user terminal with a lower rank (e.g., only one layer).

[0086] When the flexibility of layer-to-port mapping increases, the above mapping principles 1) and 2) reduce the total available number of layer-to-port mapping combinations. Therefore, if the layer-to-port mapping combinations are indexed, the number of indexes of the layer-to-port mapping combinations is reduced, and in the control information, fewer bits are required to indicate and signal the respective indexes corresponding to the layer-to-port mapping combinations.

[0087] Table 2 shows an example of the application of layer-to-port mapping principles 1) and 2). In each row, the index refers to a layer-to-port mapping combination, i.e., the number of layers of a given user equipment and the ports (port index / number) to which they can be mapped. The mapping combinations excluded by principles 1) and 2) have been eliminated. Table 2 shows 4 orthogonal ports, for example, corresponding to a single symbol DMRS of DMRS configuration 1 proposed for NR.

[0088]

[0089] Table 2 Layer to port mapping principle example

[0090] For example, mapping principles 1) and 2) are combined. In Table 2, mapping configurations that are unavailable due to continuous mapping (principle 1) are marked with an asterisk. In addition to principle 1), configurations that are unavailable due to the application of principle 2) ("higher rank priority") are marked by a hash. Principles 1) and 2).

[0091] However, as another example, each of the above-mentioned layer-to-port mapping principles 1) and 2) may be applied separately.

[0092] In addition, the application of principles 1) and 2) is not limited to the single symbol DMRS configuration 1 as shown in Table 2. Similarly, they can also be applied to other DMRS configurations with more ports, in which the impact is even more significant, because as the total number of ports increases, more layer-to-port mapping combinations can be used to exclude through either of principles 1) and 2). At the same time, due to the flexibility provided by the availability of configuring DMRS configuration types 1 and 2 and the remaining available ports, sufficient flexibility can be provided.

[0093] For example, the reference signal is a pre-reference signal, specifically a pre-DMRS. Therefore, a DMRS-based channel quality estimation can be performed before data demodulation, so that low delay of data demodulation can be achieved. However, the present disclosure is not limited to the pre-reference signal. The DMRS can also be located on any symbol of the data frame.

[0094] The resource carrying the reference signal is located on one or more symbols in the time domain. For example, according to the agreement reached for NR, the reference signal can correspond to a single-symbol DMRS or a dual-symbol DMRS. In the case of a dual-symbol DMRS, the TD-OCC is one of the resources carrying the reference signal. However, the present invention is not limited to single-symbol or dual-symbol reference signals, and more than two symbols can be used to allocate reference signals at the beginning (preamble) of the data segment or elsewhere.

[0095] For example, the mapping known to the user equipment 210 and the base station 260 implies indexing the layer-to-port mapping combinations. In the example of Table 2, the resulting index of the layer-to-port mapping combination corresponds to the number in the "Index" column of the table. In the example of Table 2, there are 15 indexed layer-to-port mapping combinations, all of which correspond to single-symbol DMRS.

[0096] However, in another example, the layer-to-port mapping combinations are indexed consecutively, including combinations with one and multiple symbols in the time domain. That is, one common index covers combinations with one symbol and combinations with two symbols. For example, the first (lower) indicates a single-symbol combination (e.g., indexes 1 to 15), followed by the index of the dual-symbol configuration (e.g., indexes 16 to 63), followed by the triple-symbol combination (if available), etc. Having such consecutive indexes, including mapping combinations with single-symbol reference signals and multiple-symbol reference signals, implicitly indicates whether there is a single-symbol reference signal, a dual-symbol reference signal, or any other number of symbols for the reference signal by indicating a specific mapping configuration.

[0097] For example, according to the first resource component configuration or the second resource component configuration, the resources assigned to the port include two resource components. The first resource component configuration includes a comb and a cyclic shift as resource components. The comb defines the difference between subcarriers, and subcarriers with alternating subcarrier indices are grouped into different combs. Therefore, the first comb consists of subcarriers with odd subcarrier indices, and the second comb consists of subcarriers with even subcarrier indices. The second resource component configuration includes frequency division multiplexing and frequency division orthogonal cover codes, OCC. Specifically, the first and second resource component configurations may correspond to the above-mentioned configuration type 1 and configuration type 2, respectively. The base station 260 configures which of the first and second resource component configurations to use, and sends an indicator (i.e., signaling information) to the user equipment 210 indicating whether the first resource component configuration or the second resource component configuration is used. The circuit 230 of the user equipment 210 receives the indicator via the transceiver unit 220 of the user equipment. For example, the indicator of the resource component configuration is sent / received via the Radio Resource Control (RRC) protocol, which covers many functional areas, such as system information, measurement configuration, and reporting.

[0098] More generally, parameters defining rules for assigning respective resources for carrying reference signals to ports are, for example, sent by the base station and received by the receiving unit via the RRC protocol.

[0099] For example, the resources assigned to the port include cyclic shift or frequency division orthogonal cover code. The circuit 280 of the base station 260, for example, configures the assignment of a first cyclic shift or frequency division orthogonal cover code applied to the first port, and the assignment of a second cyclic shift or frequency division orthogonal cover code different from the first cyclic shift or frequency division orthogonal cover code applied to the second port. The first antenna of the multiple antennas uses the first port to receive or send data, and the second antenna of the multiple antennas uses the second port to receive or send data. The reference signal can be a single symbol or a multi-symbol reference signal, and in the case of a multi-symbol reference signal, the resources assigned to the port also include TD-OCC, for example.

[0100] According to an example of the present disclosure, the base station 260 determines the carrier frequency (or multiple carrier frequencies) assigned to the user equipment 210 for transmission and / or reception, and sends an indicator indicating which carrier frequency is assigned. The user equipment 210 receives the indicator. According to the carrier frequency assigned for transmission and / or reception, the circuit 230 of the user equipment 210 configures whether each port is mapped to one symbol or the port is mapped to one or two symbols.

[0101] Thus, two variants are disclosed regarding the possibility of using a single symbol DMRS per port and using a single symbol DMRS and / or a dual symbol DMRS. Variant 1 does not specify restrictions on any reuse scheme for all frequencies; thus, a port is mapped to one or two symbols. On the other hand, for carrier frequencies above a certain threshold (e.g., 6 GHz), variant 2 does not allow dual symbol DMRS, and therefore does not allow TD-OCC.

[0102] For example, the base station 260 transmits, and the user equipment 210 receives, a carrier indicator field CIF, which specifies the carrier frequency assigned for transmission / reception. Therefore, the circuit 230 of the user equipment 210 configures whether each port is mapped to one symbol according to the above variant 2, or whether the port is mapped to one or two symbols according to variant 2, based on the frequency (or frequency interval) notified via the CIF signaling.

[0103] The present disclosure also provides a method for transmitting and / or receiving data to / from a base station 260 by a user equipment 210 using multiple antennas in a communication system. The method includes the following steps: receiving a parameter defining a rule for assigning corresponding resources for carrying reference signals to ports; generating a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station; and receiving control information indicating a layer-to-port mapping combination in the set of layer-to-port mapping combinations to be applied to data transmission and / or reception from the base station.

[0104] In addition, the present disclosure provides a method for a base station 260 to receive data from a user equipment 210 and / or send data to a user equipment 210 using multiple antennas, the method comprising: sending parameters defining a rule for allocating corresponding resources for carrying reference signals to ports; generating a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station; and sending control information to the user equipment indicating a layer-to-port mapping combination in the set of layer-to-port mapping combinations to be applied for data reception and / or transmission.

[0105] In a non-limiting and exemplary embodiment of the present disclosure, a framework is proposed that obtains input parameters from system-level information, RRC signaling and / or PDCCH signaling, utilizes these parameters, and generates a pre-DMRS port index sequence, layer-to-port mapping, and 1-symbol or 2-symbol pre-DMRS indication for a given configuration type based on predefined rules / principles. The present disclosure includes:

[0106] 1. Definition and signaling of new parameters - DMRS port index type

[0107] 2. Combinatorial principles for generating flexible layer-to-port mappings

[0108] 3. Signaling indicating single-symbol or double-symbol pre-DMRS

[0109] Figure 3 An exemplary framework for DMRS port indexing, layer-to-port mapping, and indication of single-symbol or dual-symbol DMRS for each pre-DMRS configuration is shown. Figure 3 The following steps are shown.

[0110] 1. Indicating the values ​​of the following or more parameters at the transmitting unit / receiving unit 220, 270, i.e., for data transmission and / or reception by the user equipment 210 and / or the base station 260.

[0111] a) The carrier frequency constitutes system information known to the sending unit or the receiving unit.

[0112] b) The pre-DMRS configuration type is notified to the sending unit / receiving unit via RRC signaling.

[0113] c) The DMRS port index type is notified to the transmitting unit / receiving unit through new parameter signaling via RRC or PDCCH.

[0114] Due to the new parameters according to c), the number of combinations of layer-to-port mappings can be increased by a factor of 2 without increasing the control signaling overhead if the parameters are configured via RRC.

[0115] 2. Based on the above parameters, define the port index sequence and number the orthogonal DMRS ports accordingly.

[0116] 3. Subsequently, a layer-to-port mapping table listing a set of layer-to-port mapping combinations is generated according to (one or more) predefined rules. Specifically, these rules imply mapping principles 1) and 2).

[0117] This may provide increased flexibility compared to prior art techniques while keeping overhead reasonable, especially for a large number of orthogonal ports (eg, when the resources assigned to the ports include dual-symbol DMRS). Furthermore, orthogonal mapping for MU-MIMO may be achieved.

[0118] 4. Based on the size of the table, define the bitmap size to accommodate the combination.

[0119] 5. PDCCH signaling is then used to indicate to the user the layer-to-port index for any given scenario.

[0120] like Figure 3 As shown, one aspect of the present disclosure relates to DMRS port index sequences. In current LTE, DMRS ports are assigned a fixed number regardless of the scenario. For example, ports numbered p7 to p14 are assigned to orthogonal DMRS ports in the LTE downlink, as shown in Section 29.1.1 of S. Sesia, I Toufik and M, Baker, LTE: UMTS Long Term Evolution, Second Edition. However, according to the present disclosure, port number allocation should be flexible in NR because the multiplexing scheme is different on different ports. The ability to flexibly assign port indexes adds another dimension to the problem of layer-to-port mapping combinations. In fact, the layer-to-port mapping table is transparent to this flexibility as far as the DMRS port index is concerned. Advantageously, this increases the number of combinations of layer-to-port mappings by nearly 2 times without increasing the control signaling overhead when configuring RRC.

[0121] Subsequently, it is disclosed that (one or more) rules are defined to significantly reduce the number of layer-to-port combinations while maintaining sufficient flexibility. There can be a rule or a set of rules to reduce the number of combinations. The general principle can be applied alone or in combination with more stringent rules to further reduce the number of combinations. In LTE, two separate tables are defined depending on the number of codewords for a given user. The proposed general principle is applied so that it is possible to have separate tables for one or more codewords.

[0122] In the following, it is described how the signaling is handled to indicate the presence of a single symbol or a double symbol DMRS for a given pre-DMRS configuration. A complete example of the proposed mechanism is shown below. In this example, the mechanism is applied to Figure 1C and Figure 1D The DMRS configuration shown is of configuration type 2. However, according to the present disclosure, the mechanism can be similarly applied to configuration of configuration type 2.

[0123] 1. First, RRC signaling, for example, the following parameter values:

[0124] Carrier frequency: 4GHz

[0125] Pre-DMRS configuration type: 2

[0126] Based on these parameters, two DMRS port index types (i.e., port number types) are shown for single-symbol and dual-symbol DMRS with pre-DMRS configuration type 2:

[0127] Single symbol DMRS port index type 1 (FDM->FD-OCC), such as Figure 4A This numbering type is suitable for taking advantage of more diversity in the frequency domain in the 2 or 3 port case.

[0128] Single symbol DMRS port index type 2 (FD-OCC->FDM), such as Figure 4B This type of numbering is useful for reserving resources for data multiplexing in 2, 3, or 4 port situations.

[0129] Dual-symbol DMRS port index type 1 (FDM->FD-OCC), such as Figure 5A This numbering type is suitable for taking advantage of more diversity in the frequency domain in the 2 or 3 port case.

[0130] Dual-symbol DMRS port index type 1 (FD-OCC+TD-OCC->FDM), such as Figure 5B This numbering type is suitable for taking advantage of more diversity in the frequency domain in the case of 4 to 8 ports.

[0131] exist Figure 4A , Figure 4B , Figure 5A and Figure 5B In, according to Figure 1C and Figure 1D The corresponding indication in indicates the corresponding FDM group.

[0132] 2. Second, select DMRS port index type 1, for example, configured by RRC or PDCCH. For index type 1, the port index sequence is generated in the order of FDM→FD-OCC (single symbol DMRS) or FDM→FD-OCC+TD-OCC (dual symbol DMRS). For example, "FDM→FD-OCC" means that for ports with the same FD-OCC (e.g., {1, 1}), the port index (P1 to P3) first runs across all FDM groups, and then for ports with another FD-OCC (e.g., {1, -1}), the port index (P4 to P5) runs across the FDM groups again in the same order. Similarly, in the case of FD-OCC→FDM, the index first runs through, for example, the {1, 1} ports of all FDM groups, and then maintains the same order of the FDM groups through all {1, -1} ports. The present disclosure is not limited to a specific order of FDM groups or FD-OCCs, for example, the order of FD-OCCs can be alternatively selected as first {1, -1}, then {1, 1}.

[0133] 3. Then, a table with layer-to-port mapping is generated: Based on the principle of "first mapping higher ranks on consecutive DMRS ports, and then mapping lower ranks in a consecutive manner", that is, a combination of the above-mentioned layer-to-port mapping principles 1) and 2), the following table is generated for 1-symbol DMRS (Table 3) and 2-symbol DMRS (Table 4). In the table, "State" indicates the index of the layer-to-port mapping configuration, corresponding to the "Index" column in Table 2.

[0134] state Number of layers port 1 1 P1 2 1 P2 3 1 P3 4 1 P4 5 1 P5 6 1 P6 7 2 P1, P2 8 2 P3, P4 9 2 P4, P5 10 2 P5, P6 11 3 P1-P3 12 3 P4-P6 13 4 P1-P4 14 5 P1-P5 15 6 P1-P6

[0135] Table 3 Single symbol pre-DMRS configuration 2 mapping

[0136]

[0137]

[0138]

[0139] Table 4 Dual-symbol pre-DMRS configuration 2 mapping

[0140] As can be seen from Tables 3 and 4, there are 15 states for single-symbol DMRS, which can be indicated by a 4-bit field, and 48 states for dual-symbol DMRS, which can be indicated by a 6-bit field (some states will be reserved). In addition, if the states of single-symbol DMRS and dual-symbol DMRS are combined, that is, indexed continuously by indexes running on single-symbol and dual-symbol mapping configurations, the total number will be 63, which can still be indicated by a 6-bit field. By generating an index sequence that combines the mapping combinations of single-symbol and dual-symbol layers to ports of Tables 3 and 4, respectively, and selecting an index from the combined index sequence, it is implicitly indicated whether single-symbol DMRS or dual-symbol DMRS is used. Therefore, no additional bits are required to explicitly signal the presence of 1-symbol or 2-symbol DMRS. Instead, for both single-symbol DMRS and dual-symbol DMRS of a given combination, a single bitmap is used to signal the layer to port to be applied to data transmission. Therefore, the implicit way to indicate whether single-symbol DMRS or dual-symbol DMRS exists does not require additional bits, such as a flag indicating single / dual symbol DMRS.

[0141] In the following, an exemplary case with the above parameters is considered, where there are three users / user devices. User 1 has four layers, user 2 has six layers, and user 3 has two layers. Therefore, user 2 will be mapped to P1-P6, user 1 (i.e., user 1's layers) will be mapped to P7-P10, user 3 will be mapped to P11-P12, and the following bitmaps will be transmitted to each user respectively: (for the combined state with a single bitmap).

[0142] User 1: Index (15+34) 49->110001

[0143] User 2: Index (15+41)55->110111

[0144] User 3: Index (15+22)37->100101.

[0145] In the following, non-limiting examples of allocating resources to ports according to configuration type and carrier frequency are provided.

[0146] For centimeter / millimeter wave bands (referring to frequency bands above 6 GHz) and pre-DMRS configuration type 1, depending on the signaling of the port order, when TD-OCC is not allowed, select "comb->CS" or "CS->comb", otherwise select "comb->TD-OCC->CS" or "TD-OCC->CS->comb", higher ranks are first mapped on consecutive DMRS ports, followed by lower ranks in a continuous manner, and a single bitmap is used for signaling.

[0147] For cm / mm wave bands and pre-DMRS configuration type 2, depending on the signaling of the port order, when TD-OCC is not allowed, select "FDM->FD-OCC->ScID" or "FD-OCC->ScID->FDM", otherwise select "FDM->FD-OCC->TD-OCC" or "FD-OCC->TD-OCC->FDM", higher ranks are first mapped to consecutive DMRS ports, followed by lower ranks in a consecutive manner, and a single bitmap is used for signaling.

[0148] For frequencies below cm / mm wave band and pre-DMRS configuration type 1, depending on the signaling of the port order, "Comb->TD-OCC->CS" or "TD-OCC->CS->Comb" is selected, and higher ranks are first mapped to consecutive DMRS ports, followed by lower ranks in a consecutive manner, and a single bitmap is used for signaling.

[0149] For frequencies below cm / mm wave band and pre-DMRS configuration type 2, depending on the signaling of the port order, "FDM->FD-OCC->TD-OCC" or "FD-OCC->TD-OCC->FDM" is selected, and higher ranks are first mapped to consecutive DMRS ports, followed by lower ranks in a consecutive manner, and a single bitmap is used for signaling.

[0150] The DMRS port index type is also shown in Table 5 and Table 6. More options are possible, but not required.

[0151]

[0152]

[0153] Table 5 has no restrictions on any reuse scheme for all frequencies (Variant 1)

[0154]

[0155] Table 6 TD-OCC is not applicable to carrier frequencies above 6 GHz (Variant 2)

[0156] In one general aspect, the present disclosure provides a user equipment for transmitting data to a base station and / or receiving data from a base station using multiple antennas in a communication system. The user equipment includes a circuit that receives parameters defining a rule for assigning corresponding resources for carrying reference signals to ports, generates a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station, and receives control information from the base station indicating a layer-to-port mapping combination in the set of layer-to-port mapping combinations to be applied to data transmission and / or reception.

[0157] This helps support flexible configuration of single or dual symbol DMRS within various pre-DMRS configurations and flexible layer-to-port mapping while maintaining reasonable signaling overhead.

[0158] For example, the rules also define a sequence of port indices, and the mapping specifies that each combined layer is mapped to consecutively indexed ports.

[0159] For example, the mapping further indicates that each layer of a first configuration is mapped to a port with an index that is less than the index of each port to which any layer of a second configuration is mapped, the first configuration having a higher rank than the second configuration, the rank being the number of layers of the configuration.

[0160] These rules help keep a reasonable number of layer-to-port mapping combinations while providing flexible layer-to-port mappings.

[0161] In some embodiments, the resource carrying the reference signal is located on one or more symbols in the time domain.

[0162] For example, the mapping implies indexing combinations of mapping layers to ports, and these combinations are indexed consecutively, including combinations with one or more symbols in the time domain.

[0163] This provides a way to implicitly signal whether a combination with one or more reference signals is used.

[0164] In some exemplary embodiments, the resources assigned to the port include two resource components, the first resource component configuration includes a cyclic shift of a reference signal and a comb tooth, the comb tooth consisting of subcarriers with odd subcarrier indices or subcarriers with even subcarrier indices, the second resource component configuration includes frequency division multiplexing and frequency division orthogonal cover codes, OCC, and the circuit of the user equipment also receives an indicator from the base station indicating whether to use the first resource component configuration or the second resource component configuration.

[0165] For example, parameters defining rules for assigning respective resources for carrying reference signals to ports are received via a Radio Resource Control, RRC, protocol.

[0166] This helps increase the number of layer-to-port mapping combinations without increasing signaling overhead.

[0167] In some embodiments, the processing circuitry of the user equipment configures whether each port is mapped to one symbol or a port is mapped to one or two symbols according to the carrier frequency assigned for transmission and / or reception.

[0168] For example, the circuitry of the user equipment also receives a carrier indicator field CIF, which specifies the carrier frequency.

[0169] In some embodiments, the reference signal is a pre-demodulation reference signal.

[0170] In some embodiments, the user equipment further comprises a transceiver unit that performs data transmission and / or reception of a layer-to-port mapping combination indicated by the application.

[0171] Also provided is a base station for receiving and / or sending data from / to a user equipment in a communication system, the base station comprising a plurality of antennas that send or receive data; and a circuit that sends parameters defining rules for assigning corresponding resources for carrying reference signals to ports, generates a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station, and sends control information to the user equipment indicating a layer-to-port mapping combination from the set of layer-to-port mapping combinations to be applied for data reception and / or transmission.

[0172] In some embodiments, parameters defining rules for assigning respective resources for carrying reference signals to ports are transmitted via a Radio Resource Control, RRC, protocol.

[0173] Furthermore, in some embodiments, the circuitry of the base station is further configured to define rule parameters for allocating corresponding resources for carrying reference signals to ports.

[0174] For example, the resources assigned to the ports include cyclic shift or frequency division orthogonal cover codes, and the circuit further configures the assignment of a first cyclic shift or frequency division orthogonal cover code applied to the first port,

[0175] and an assignment of a second cyclic shift or frequency division orthogonal cover code different from the first cyclic shift or frequency division orthogonal cover code applied to a second port, a first of the plurality of antennas receiving or transmitting data using the first port, and a second of the plurality of antennas receiving or transmitting data using the second port.

[0176] According to another general aspect, a method for transmitting and / or receiving data by a user equipment to / from a base station using multiple antennas in a communication system is disclosed, the method comprising the following method steps: receiving parameters defining a rule for assigning corresponding resources for carrying reference signals to ports, generating a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station, and receiving control information from the base station indicating a layer-to-port mapping combination from the set of layer-to-port mapping combinations to be applied for data transmission and / or reception.

[0177] Also disclosed is a method for receiving data from a user equipment and / or sending data to a user equipment by a base station using multiple antennas, the method comprising: sending parameters defining rules for assigning corresponding resources for carrying reference signals to ports; generating a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station; and sending control information to the user equipment indicating a layer-to-port mapping combination in the set of layer-to-port mapping combinations to be applied for data reception and / or transmission.

[0178] In summary, the present disclosure relates to a user equipment, a base station, a data transmission / reception method of the user equipment, and a data reception / transmission method of the base station. The user equipment includes a circuit that receives parameters defining a rule for assigning corresponding resources for carrying reference signals to ports, generates a set of layer-to-port mapping combinations based on mappings known to the user equipment and the base station, and receives control information from the base station indicating a layer-to-port mapping combination in the set of layer-to-port mapping combinations to be applied to data transmission and / or reception.

Claims

1. An integrated circuit for controlling a user equipment that sends and / or receives data to / from a base station, comprising: Control circuit, receiving parameters defining rules for assigning to ports respective resources for carrying reference signals, Based on the mappings known to the user equipment and the base station, generating a set of layer-to-port mapping combinations, and receiving, from a base station, control information indicating one layer-to-port mapping combination from a set of layer-to-port mapping combinations to be applied to data transmission and / or reception, in, In the set of layer-to-port mapping combinations, dual-symbol layer-to-port mapping combinations for multiple layers include mapping combinations with consecutive port numbers, at least one of which is duplicated in a subsequent mapping combination of the same multiple layers and consecutive indexes.

2. The integrated circuit of claim 1, wherein The rules also define a sequence of port indices, and The mapping specifies that each combined layer is mapped to consecutively indexed ports.

3. The integrated circuit according to claim 2, wherein: The mapping also indicates that each layer of a first configuration is mapped to a port with an index that is less than the index of each port to which any layer of a second configuration is mapped, the first configuration having a higher rank than the second configuration, the rank being the number of layers of the configuration.

4. An integrated circuit according to any one of claims 1 to 3, in, The resource carrying the reference signal is located on one or more symbols in the time domain.

5. The integrated circuit according to claim 4, wherein: The mapping implies mapping combinations of indexed layers to ports, and the combinations are indexed consecutively, including combinations with both one and multiple symbols in the time domain.

6. The integrated circuit according to any one of claims 1 to 3, wherein: The resources allocated to the port include two resource components, The first resource component configuration includes a cyclic shift of a reference signal and a comb tooth, the comb tooth consisting of subcarriers with odd subcarrier indices or subcarriers with even subcarrier indices, The second resource component configuration includes frequency division multiplexing and frequency division orthogonal cover codes OCC, and The control circuit also receives an indicator from a base station indicating whether to use the first resource component configuration or the second resource component configuration.

7. The integrated circuit according to any one of claims 1 to 3, wherein: Parameters defining rules for allocating respective resources for carrying reference signals to ports are received via the Radio Resource Control, RRC, protocol.

8. The integrated circuit according to any one of claims 1 to 3, wherein: The control circuit configures whether each port is mapped to one symbol or whether the port is mapped to one or two symbols according to the carrier frequency assigned for transmission and / or reception.

9. The integrated circuit of claim 8, wherein: The control circuit also receives a carrier indicator field CIF, specifying the carrier frequency.

10. The integrated circuit according to any one of claims 1 to 3, wherein the reference signal is a pre-demodulation reference signal.

11. The integrated circuit according to any one of claims 1 to 3, further comprising a transceiver unit circuit that performs data transmission and / or reception using the indicated layer-to-port mapping combination.

12. An integrated circuit for controlling a base station for receiving and / or transmitting data from / to a user equipment, comprising Control circuit, sending parameters defining rules for allocating to ports corresponding resources for carrying reference signals, Based on the mappings known to the user equipment and the base station, generating a set of layer-to-port mapping combinations, and sending control information indicating one layer-to-port mapping combination from a set of layer-to-port mapping combinations to be applied to data reception and / or transmission to a user equipment, in, In the set of layer-to-port mapping combinations, dual-symbol layer-to-port mapping combinations for multiple layers include mapping combinations with consecutive port numbers, at least one of which is duplicated in a subsequent mapping combination of the same multiple layers and consecutive indexes.

13. The integrated circuit of claim 12, wherein: Parameters defining rules for allocating respective resources for carrying reference signals to ports are sent via the Radio Resource Control, RRC, protocol.

14. The integrated circuit of claim 12, wherein: The control circuitry also configures parameters defining rules for assigning respective resources to ports for carrying reference signals.

15. An integrated circuit according to claim 12 or 13, wherein: The resources assigned to the port include cyclic shift or frequency division orthogonal cover codes, and the control circuit is further configured an assignment of a first cyclic shift or frequency division orthogonal cover code applied to the first port, an assignment of a second cyclic shift or frequency division orthogonal cover code different from the first cyclic shift or frequency division orthogonal cover code applied to the second port, A first one of the plurality of antennas receives or transmits data using the first port, and A second one of the plurality of antennas receives or transmits data using the second port.

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