CN107257252A

CN107257252A - For coordinating multiple points（CoMP）Downlink in system（DL）The Timing Synchronization of transmission

Info

Publication number: CN107257252A
Application number: CN201710477754.XA
Authority: CN
Inventors: A.达伊多夫; G.莫罗佐夫; A.马特塞; V.塞格耶; I.博洛廷
Original assignee: Intel Corp
Current assignee: Apple Inc
Priority date: 2011-11-04
Filing date: 2012-06-05
Publication date: 2017-10-17
Anticipated expiration: 2032-06-05
Also published as: RU2669781C1; RU2643660C1; RU2656234C1; MY175550A; RU2632902C1; JP2016059062A; CA2932387C; HUE035205T2; JP2017077013A; JP2018196127A; JP6424398B2; CN107257252B; HK1249286A1; JP2017085581A; JP2016129383A; RU2612411C2; JP6371361B2; JP6501210B2; JP6726815B2; RU2015138682A

Abstract

Disclose in coordinating multiple points（CoMP）The technology of the receiver timing of wireless device is adjusted in system.A kind of method may include that wireless device receives multiple node specific reference signals from multiple cooperative nodes in the coordination group of CoMP system（RS）.Coordination group includes at least two cooperative nodes.Wireless device can receive RS timings from the synthesis of multiple reception RS timing estimations, and multiple reception RS timings are generated from the specific RS of multiple nodes.Receive RS timings and represent the timing from least two cooperative nodes.Wireless device can receive the timing of RS timing adjustments receiver based on synthesis.The specific RS of node may include channel state information reference signals（CSI‑RS）.

Description

The Timing Synchronization transmitted for downlink (DL) in coordinating multiple points (CoMP) system

Related application

It is P41399Z, Serial No. 61/556109 this application claims the attorney docket submitted on November 4th, 2011 U.S. Provisional Patent Application rights and interests, and be incorporated by reference herein.

Background technology

Wireless mobile telecommunication technology is passed using various standards and agreement in node (for example, transfer station) between wireless device Send data.Some wireless devices use the OFDM (OFDM) for combining required digital modulation scheme to carry out via physical layer Communication.Include third generation cooperative partner program (3GPP) Long Term Evolution (LTE), Electrical and Electronic using OFDM standard and agreement The standard (for example, 802.16e, 802.16m) of IEEE (IEEE) 802.16 (is commonly referred to as the WiMAX (whole world to industrial colony Microwave access intercommunication)), and the standards of IEEE 802.11 (being commonly referred to as WiFi to industrial colony).

In 3GPP radio access networks (RAN) LTE system, node can be the universal terrestrial radio access network of evolution (E-UTRAN) Node B (also commonly referred to as evolved Node B, enhanced Node B, eNodeB, or eNB) and radio net The combination of controller (RNC), the wireless device (for example, mobile device) of the node and referred to as user equipment (UE) is led to Letter.Downlink (DL) transmission can be communication from node station (or eNodeB) to wireless device (or UE), and uplink Road (UL) transmission can be the communication from wireless device to node.

In homogeneous network, wireless device that also referred to as node of grand node can be into cell provides basic wireless cover Lid.Cell can be the wireless device operable region to be communicated with grand node wherein.Due to the increase of wireless device Use and feature, heterogeneous network (HetNet) is used to handle increased traffic load in grand node.HetNet can The layer of high power grand node (or grand eNB) including planning, the layer is by lower-wattage node (micro- eNB, micro, slight eNB, femto ENB, or family eNB [HeNB]) layer covering, the lower-wattage node may be not so good or even completely uncoordinated to plan Mode be deployed in the area of coverage (cell) of grand node.Lower-wattage node (LPN) may be referred to collectively as " low power nodes ".Grand section Point can be used for basic covering, and low power nodes can be used to fill covering leak, to improve in hot zone or covering in grand node The capacity on the border between cover region, and improve in-door covering in place of building structure hinders signal to transmit.Inter-cell interference is assisted (ICIC) or enhanced ICIC (eICIC) is adjusted to can be used for resource coordination, to reduce node (grand node in such as HetNet and low Power node) between interference.

Brief description of the drawings

The feature and advantage of the disclosure by from the detailed description carried out below in conjunction with the accompanying drawings, it is evident that accompanying drawing is lifted jointly The feature of the example explanation disclosure, wherein：

Fig. 1 shows the orthogonal frequency come the grand node in self-coordinating group and low power nodes (LPN) according to an example It is multiplexed (OFDM) symbol transmission, the OFDM symbol received in wireless device and fixed using earliest reception reference signal (RS) When adjust FFT (FFT) window schematic diagram；

Fig. 2 shows the orthogonal frequency come the grand node in self-coordinating group and low power nodes (LPN) according to an example It is multiplexed (OFDM) symbol transmission, the OFDM symbol received in wireless device and using Reference Signal Received Power (RSRP) With the schematic diagram for receiving reference signal the FFT of (RS) timing adjustment (FFT) window；

Fig. 3 shows the orthogonal frequency division multiplexing come multiple cooperative nodes in self-coordinating group all (OFDM) symbol according to an example Number transmission, the OFDM symbol that is received in wireless device and using Reference Signal Received Power (RSRP) and receive with reference to believing The schematic diagram of number FFT of (RS) timing adjustment (FFT) window；

Fig. 4 shows to be accorded with according to the OFDM (OFDM) come multiple cooperative nodes in self-coordinating group of an example Number transmission, the OFDM symbol that is received in wireless device and the quick Fourier using the adjustment cooperative nodes of timing adjustment first The schematic diagram of leaf inverse transformation (IFFT) window；

Fig. 5 shows the block diagram of the radio frame resource according to an example；

Fig. 6 shows the timing transmitted according to the downlink (DL) being used in coordinating multiple points (CoMP) system of an example Synchronous flow chart；

Fig. 7 is shown according to the transmitter and receiver in OFDM (OFDM) wireless network of an example The block diagram of physical layer；

Fig. 8 shows to be determined according to the receiver for being used to adjust wireless device in coordinating multiple points (CoMP) system of an example When method flow chart；

Fig. 9 show according to example be used for make the descending chain of the first cooperative nodes in coordinating multiple points (CoMP) system Flow chart of the timing of road (DL) transmission relative to the method for the downlink transmission synchronization of the second cooperative nodes；

Figure 10 shows the block diagram of the wireless device and multiple cooperative nodes according to example；And

Figure 11 shows the schematic diagram of the wireless device according to an example.

Now with reference to shown exemplary embodiment, and language-specific will be used herein to describe these implementations Example.It will be appreciated, however, that not really wanting thus to limit the scope of the present invention.

Embodiment

Before the present invention is disclosed and described, it will be appreciated that the invention is not limited in specific knot disclosed herein Structure, process steps or material, but expand to the equivalent that those of ordinary skill in the related art can recognize.It is also understood that Term employed in this paper is only used for describing the purpose of particular example, rather than to be defined.In different drawings, phase Same reference represents identical element.Flow chart and during the numeral that provides be to clearly illustrate step and behaviour Make and provide, specific order or sequence might not be indicated.

Example embodiment

The preliminary general introduction of technical em- bodiments is provided below, then, specific technical em- bodiments are described in further detail later. This preliminary general introduction is intended to help reader more quickly to understand this technology, but does not really want the key feature or necessity of identification technology Feature, nor to limit the scope of theme claimed.

Coordinating multiple points (CoMP) system can be used to reduce the interference from adjacent node in homogeneous network and HetNet. In coordinating multiple points (CoMP) system, referred to as the node of cooperative nodes also can be together with the marshalling of other nodes, wherein from many The node of individual cell can transmit signal and receive signal to wireless device and from wireless device.Cooperative nodes can be in homogeneous network In node or grand node and/or lower-wattage node (LPN) in HetNet.Downlink CoMP transmission can be divided into two Class：Coordinated scheduling or coordinating beam forming (CS/CB or CS/CBF), and Combined Treatment or joint transmission (JP/JT).Using CS/CB, given subframe can be sent to given wireless device (UE) from a cell, and dispatch, including coordinate wave beam Shape, between cells dynamic coordinate, to control and/or reduce the interference between different transmission.For Combined Treatment, it can lead to Multiple cells are crossed to perform joint transmission to wireless device (UE), wherein, multiple nodes use identical time and frequency wireless Electric resources and/or dynamic cell selection are transmitted simultaneously.

In non-CoMP system, it can be entered by using master sync signal (PSS) and/or cell specific reference signal (CRS) Timing Synchronization of the row in wireless device (for example, UE).As shown in figure 1, in downlink (DL) CoMP system and with difference In the deployment of the spaced antenna in geographical position, using PSS and/or CRS be timed estimation may it is inaccurate because PSS and/ Or CRS transfer points (for example, grand node 210 in macrocell 212) may be passed with physical down link sharing channel (PDSCH) Defeated point (for example, lower-wattage node [LPN] 220 in LPN cells 222) differs.Using public small shown in Fig. 1 In dynamic point selection (DPS) DL CoMP examples of area's identifier (ID), from grand node to wireless device (for example, UE 230) DL transmits 250 (including PSS and/or CRS) and the separated DL from LPN to wireless device transmits 260 (including data or PDSCH) Can substantially the identical time transmitted.Due to the diverse geographic location of node (for example, grand node and LPN) and/or other Factor, DL transmission can reach wireless device in the different time.Wireless device can be synchronized to PSS and/or CRS transfer points (for example, Grand node).For example, due to propagation delay, transmit OFDM (OFDM) symbol in 252 in grand node and passed in LPN Substantially the same OFDM symbol in defeated 262 can be received by wireless device (for example, UE) in the different time.OFDM symbol can Including cyclic prefix (CP).Because UE is received and can had closer to LPN rather than grand node, therefore the UE of grand node DL transmission 254 There is the propagation delay 256 bigger than the propagation delay 266 that the LPN DL UE for transmitting 264 are received.If the PSS from grand node And/or CRS is used for Timing Synchronization, the timing of FFT (FFT) window 280 for being sampled to OFDMA symbol can Grand node DL transmission is synchronized to, the transmission may not be transmission earliest in coordination group.Therefore, wireless device possible application comes from The transmission of (in the coordination group) other nodes of the timing with the OFDM symbol shifted to an earlier date relative to FFT sampling windows.In addition, In some cases, the transmission from grand node may be without peak signal power (for example, Reference Signal Received Power (RSRP)) and/or provide data transfer (for example, PDSCH).In these cases, inter-carrier interference (ICI) and intersymbol interference (ISI) 270 may occur due to the incorrect setting in the FFT timings of wireless device.In order to reduce ICI and ISI and change Kind OFDMA symbol is received, and can adjust receiver timing, this can offset FFT windows.Can be in the FFT windows for receiving OFDM symbol Multiple FFT samples of OFDM symbol are captured in mouthful.Although showing grand node and LPN in Fig. 1-2, DL CoMP are may be used at Any kind of node in system.

The Timing Synchronization of the receiver timing of wireless device can be modified to use the specific ginseng of node from CoMP measurement groups The timing estimation of signal generation is examined, wherein basic Timing Synchronization uses PSS and/or CRS.Node specific reference signals may include letter Channel state information reference signal (CSI-RS).Receiver timing can be the timing of receiver inter-process, such as when receiver is sought Look for the timing on OFDM symbol border or at the time of receiver carries out FFT (for example, being sampled to OFDM symbol).Because different CSI-RS configurations can be assigned to that different geographically separated transfer points (for example, grand node and LPN), for each transmission point Estimation can be independently timed.Based on multiple timing estimations from CSI-RS, wireless device can be calculated from multiple nodes Data or PDSCH receive actual timing.

In one example, wireless device can be from multiple associations in the coordination group (for example, CoMP measurements group) of CoMP system Same node (for example, grand node and LPN) receives multiple node specific reference signals (RS), such as CSI-RS.Coordination group may include At least two cooperative nodes.Cooperative nodes may include service node, grand node or LPN.Wireless device can be from least two collaborations The specific RS of node receiving node.Wireless device can receive RS timings from the specific RS generations of node or calculating of cooperative nodes.Wirelessly Equipment can receive RS timings from the synthesis of multiple reception RS timing estimations.Receiving RS timings can represent to come from least two cooperative nodes Timing.Wireless device can receive the timing of RS timing adjustments receiver based on synthesis.The receiver timing adjusted can be nothing The receiver of line equipment is received signal or OFDM symbol sampling, the time for carrying out or handling FFT.

In one embodiment, what wireless device can be earliest from the multiple reception RS timing determinations for representing various cooperative nodes Receive RS timings.For adjust receiver timing and/or FFT windows estimated by synthesis receive RS timing can be used or including Earliest reception RS timings 282.Earliest reception RS timings can represent there is most short propagation delay relative to other cooperative nodes DL transmission.Estimated synthesis receives the PDSCH timings τ of RS timings or reality_PDSCHIt can be arranged in CoMP measurement groups All timings calculatedIn earliest timing, byTo represent, wherein, τ_PDSCHIt is thing Downlink sharied signal channel (PDSCH) timing is managed,It is the channel status calculated for each node in CoMP measurement groups Information reference signal (CSI-RS) timing, min () is minimum value function, and i is to represent node in CoMP measurement groups just Integer (that is, has i node) in CoMP measurement groups.In wireless device, based on earliest reception RS timing adjustment receivers Timing or FFT windows can reduce the timing of the signal shifted to an earlier date relative to the FFT sampling intervals of wireless device.In an example In, receive the joint transmission (JP/ that RS timings can be used for Combined Treatment (JP) using the estimated synthesis of earliest reception RS timings JT in), then, the CSI-RS timings of nearest node are may correspond to adjust the FFT sampling intervals., can in joint transmission (JT) PDSCH is transmitted from multiple cooperative nodes of cooperation district.

In another embodiment, what wireless device can be minimum from the multiple reception RS timing determinations for representing various cooperative nodes Receive RS timings and maximum reception RS timings.It can substantially determine in minimum reception RS that the synthesis of estimation, which receives RS timings, When and maximum receptions RS timings between value or receiver RS regularly.As shown in figure 3, minimum reception RS timings 362 can be wrapped Include the earliest reception RS timings that the DL for representing there is most short propagation delay relative to other cooperative nodes is transmitted.Maximum reception RS timings 364 may include to represent that the reception RS at the latest that the DL for having most long propagation delay relative to other cooperative nodes is transmitted determines When.

In another embodiment, by the Reference Signal Received Power (RSRP) for cooperative nodes and from cooperative nodes The combinations of the receptions RS timings of node specific RS generations is determined or calculated for adjusting receiver regularly and/or FFT windows Synthesis receives RS timings.For example, the synthesis that the weighted sum of CSI-RS timings can be used to calculate estimation receives RS timings 284 or real Border timing, byRepresent, wherein, τ_PDSCHIt is physical down link sharing channel (PDSCH) timing,Be CoMP measurement groups channel state information reference signals (CSI-RS) timing calculated in each,It is CSI-RS antenna port received signal powers, i is the positive integer for representing the node in CoMP measurement groups, and f () is the monotonic function of its independent variable (that is, function argument).Can be right based on RSRP adjustment receiver timings or FFT windows The OFDM symbol received from channel or signal with maximum or peak signal power provides weight or priority.Using with reference to letter Number receiving power (RSRP) and synthesis for the combination of the reception RS timings of cooperative nodes receive RS timings can be in Combined Treatment (JP) dynamic point selection (DPS) or dynamic cell selects to use in (DCS).In dynamic cell selection (DCS), from coordination group In single cooperative nodes transmission PDSCH, this can be dynamically selected.

In another embodiment, transmission cooperative nodes or controller in the core network can be selected from multiple cooperative nodes The selected cooperative nodes of institute, to be used to refer to cooperative nodes in the receiver timing of regulation wireless device.Sending cooperative nodes can To be and selected cooperative nodes identical cooperative nodes or different cooperative nodes.Transmission cooperative nodes are transmittable to select association Selection with node is to wireless device.Wireless device can receive the selection of the selected cooperative nodes from the cooperative nodes.Institute The selection of selected cooperative nodes can be transmitted or accused with signal in the down link control information (DCI) for the wireless device Know.Wireless device can receive multiple specific RS of node from various cooperative nodes.Wireless device can determine cooperative nodes from from selected Node specific RS generation synchronization RS regularly.Synchronous RS timings can be used to by received data or the physical down chain received The receiver timing (being used for Timing Synchronization) of road shared channel (PDSCH) adjustment wireless device.The synthesis receives RS timings can Including synchronous RS timings.By this way, in the core network cooperative nodes (for example, sending cooperative nodes) or controller are optional The RS timings that synthesis receives RS timings will be used for by selecting, and synthesis, which receives RS timings, to be used to adjust receiver timing to receive PDSCH.

Fig. 3 shows to adjust the receiver timing of the wireless device in coordinating multiple points (CoMP) system, coordinating multiple points (CoMP) system has two cooperative nodes 310A-B (for example, first and second cooperative nodes), the specific ginseng of their transmission nodes Examine wireless devices 330 of signal (NS-RS) 350A-B into coordination group 320.Wireless device can by initial synchronisation to PSS and/or CRS transfer points (for example, second cooperative nodes).For example, due to propagation delay, the OFDM in the first cooperative nodes transmit 352B Symbol and substantially the same OFDM symbol in the second cooperative transmission 352A can be received by wireless device in the different time. Because wireless device is transmitted closer to the first cooperative nodes rather than the second cooperative nodes, therefore the second cooperative nodes (CN) DL 354A wireless device (WD), which is received, can have what is received than the first cooperative nodes (CN) DL wireless devices (WD) for transmitting 354B Propagation delay 356A bigger propagation delay 356B.If PSS and/or CRS from grand node be used for Timing Synchronization, for pair The timing of FFT (FFT) window 380 of OFDM symbol sampling can be synchronized to grand node DL transmission.Connect for adjusting The synthesis of the timing of receipts machine and/or the estimation of FFT windows receives RS timings 384 and can be used or including earliest reception RS timings, Or can determine or calculate by the combination of the Reference Signal Received Power (RSRP) for cooperative nodes and reception RS timings. Before reception RS timing of the wireless device generation from multiple cooperative nodes, cooperative nodes can transmit the specific RS of node to wireless Equipment.

Fig. 4 is shown in coordinating multiple points (CoMP) system, in order to reduce ICI and ISI, transmits the DL of the first cooperative nodes The timing another example synchronous relative to the downlink transmission of the second cooperative nodes.Can substantially the identical time from two Individual cooperative nodes receive OFDM symbol.Adjustment timing 396 can make in the transmitter timing device of cooperative nodes, and it can offset soon Fast inverse fourier transform (IFFT) modulates window.IFFT modulators or IFFT modules can be used for generation modulated signal.Wireless device RS timings or the first cooperative nodes reception from the specific RS generations of node from the first cooperative nodes can will be received including synthesis The timing feedback of RS timings is sent to the first cooperative nodes.First cooperative nodes can receive timing feedback from wireless device.First Cooperative nodes can be used synthesis receive RS timings or the first cooperative nodes to receive RS timings 396 descending to change by adjusting timing Link transmission timing (for example, the first cooperative nodes DL transmission 392).Modification downlink transmission timing may include to connect according to synthesis Receive RS timings or the first cooperative nodes receive RS timings and are used for the descending of downlink transmission to offset (for example, being retarded or advanced) Fast fourier inverse transformation (IFFT) timing of link signal.394 wireless device is transmitted in the first cooperative nodes (CN) DL (WD) change in receiving can reduce the time between the reception RS timings of minimum and the reception RS timings of maximum, and this can make to be connect The OFDM symbol of receipts is alignd and reduces ICI and ISI.In another example, at least two associations in multiple cooperative nodes Downlink transmission with node can be by wireless device substantially identical time reception.In another example, collaboration section The DL transmission of point, which is adjustable to, makes the reception in the DL transmission of wireless device be synchronized with the timing specified, such as existing PSS And/or CRS.

In another example, the node spy come from from multiple cooperative nodes can be used in the receiver timing of wireless device Determine RS information to adjust, and the transmitter timing of at least one cooperative nodes can be used timing feedback to adjust, to reduce Time between minimum reception RS timings and the reception RS timings of maximum.

In one example, as shown in figure 5, OFDM symbol and the specific RS of node can represent to use general Long Term Evolution (LTE) frame structure between node (or eNodeB) and wireless device (or UE) downlink transmission or up-link transmission in The element of the radio frame structure transmitted on physics (PHY) layer.Although showing LTE frame structures, it can also be used for using The frame knot of OFDM standards of IEEE 802.16 (WiMax), the standards of IEEE 802.11 (WiFi) or another type of communication standard Structure.

Fig. 5 shows downlink radio frame structure type 2.In this example, for transmit data signal it is wireless Electric frame 100 can be configured with the duration T of 10 milliseconds (ms)_f.Each radio frame sectional is divided into 10 sons Frame 110i, each long 1ms.Each subframe can be further divided into two time slots 120a and 120b, each time slot it is lasting when Between T_slotFor 0.5ms.The each time slot for the component carrier (CC) that cell site and receiving station use can be included based on CC frequency bandwidths Multiple resource block (RB) 130a, 130b, 130i, 130m and 130n.CC can have the carrier frequency with bandwidth and centre frequency.Often Individual RB (physics RB or PRB) 130i may include 12-15kHz subcarriers 136 (on the frequency axis) and each subcarrier has 6 or 7 Individual OFDM (OFDM) symbol 132 (on a timeline).If using short or normal cyclic prefix, RB can be used 7 OFDM symbols.If using the cyclic prefix of extension, 6 OFDM symbols can be used in RB.When using short or normal circulation During prefix, resource block is mapped to 84 resource element (RE) 140i, or using the cyclic prefix of extension, resource block can quilt It is mapped to 72 RE (not shown).RE can be the list that an OFDM symbol 142 is multiplied by a subcarrier (that is, 15kHz) 146 Member.In the case where QPSK (QPSK) is modulated, each RE can transmit two bits 150a and 150b information.It can make With other types of modulation, such as 16 quadrature amplitude modulations (QAM) or 64QAM in each RE to transmit greater number of ratio Spy, or two-phase PSK (BPSK) are modulated to transmit small number of bit (individual bit) in each RE.RB can quilt The downlink transmission from eNodeB to UE is configured to, or the up-link that RB can be arranged to from UE to eNodeB is passed It is defeated.

Reference signal can usually be transmitted by OFDM symbol via the resource element in resource block.Reference signal (or pilot tone Signal or single-tone) can be used for the known letter of various reasons (noise in such as synchronization timing, estimation channel and/or channel) Number.Reference signal can be launched station and mobile communication equipment is received and transmitted.Different types of reference signal (RS) can be in RB Use.For example, in LTE system, downlink reference signal type may include cell specific reference signal (CRS), multicast it is wide Broadcast SFN (MBSFN) reference signal, UE specific reference signals (UE specific RS or UE-RS) or demodulated reference signal (DMRS), Location reference signals (PRS) and channel state information reference signals (CSI-RS).

CRS can be transmitted in the cell for supporting PDSCH in downlink subframe.Via PDSCH number is transmitted from eNodeB According to UE.When transmitting Physical Multicast Channel (PMCH) in the MBSFN subframe, MBSFN reference signals are can transmit.UE-RS or DMRS can be transmitted in the downlink subframe for supporting PDSCH.UE-RS (DMRS) can be allocated for the shared letter of downlink Particular terminal (for example, mobile communication equipment) is sent in the resource block of road (DL-SCH) transmission, for using multiple antennas Beam forming is carried out to single UE, and for PDSCH demodulation.PRS can be in the downlink subframe for being configured to PRS transmission Transmitted in RB, but Physical Broadcast Channel (PBCH), master sync signal (PSS) or auxiliary synchronous signals may not be mapped to (SSS).CSI-RS can be used for downlink channel quality.

Fig. 6 shows to be used for the Timing Synchronization 560 of downlink (DL) transmission in coordinating multiple points (CoMP) system and additional The example flow diagram of Timing Synchronization 580.Originally, PSS and/or CRS 562 from cooperative nodes can be used to produce for wireless The timing estimation of the receiver of equipment.It can be assembled by the generation CoMP measurements of at least one cooperative nodes and put 572.In another embodiment In, assembled by least one cooperative nodes from the controller reception CoMP measurements in core net and put 572.CoMP measurements assemble what is put At least one section may be sent to that wireless device.Be sent to the section of the CoMP measurement groups of wireless device may include be used for node it is specific Cooperative nodes in the coordination group of RS (for example, CSI-RS) measurement.Additional Timing Synchronization may include to be used for CoMP measurements group 582 In each CSI-RS antenna ports timing estimation, and receive RS timings from this estimated group timing to calculate synthesis 584, the actual timing of the receiver for adjusting or producing wireless device.

On the basis of only with PSS, SSS and/or CRS signal control Timing Synchronization, node specific RS or CSI-RS is used Additional Timing Synchronization receiver timing can be allowed to be adjusted, to receive OFDM data symbol from different cooperative nodes so that Most of OFDM symbol borders fall within the protection interval of OFDM symbol, and this can reduce ICI and ISI.Receiver timing can be wrapped The timing of receiver inter-process, the timing when receiver searching OFDM symbol border are included, or when receiver is carried out or sampling FFT At the time of.Additional Timing Synchronization uses some reception reference signals timing from different cooperative nodes, rather than only from list PSS, SSS and/or CRS signal of individual node.Each reference signal (RS) that receives can be regularly to come from i-th of cooperative nodes, Wherein i is the positive integer for representing the node in CoMP measurement groups.OFDM symbol border can be in the letter received from i-th of cooperative nodes In number, i-th of cooperative nodes may include service node.The section from i-th of cooperative nodes can be used in the value of received RS timings Specific RS or CSI-RS is put to measure or generate.Timing may include possible delay, and such as emitter (TX) delay, propagation are prolonged Late, receiver (RX) delay and other processing delays.

Fig. 7 shows ofdm demodulator, including in a wireless device for the FFT demodulation in the receiver (RX) of downlink Device；And OFDM modulators, it is included in cooperative nodes for the IFFT modulators in the emitter of downlink.It can be used attached Plus Timing Synchronization is the timing that OFDM symbol adjusts FFT demodulators.

Wireless communication system can be subdivided into the various parts of referred to as layer.In LTE system, communication layers may include physics (PHY), medium education (MAC), radio link control (RLC), PDCP (PDCP) and radio money Source controls (RRC) layer.As shown in fig. 7, physical layer may include the basic hardware transmission assembly of wireless communication system 400.Basic Multiple-input and multiple-output (MIMO) system is used to briefly describe basic hardware transmission assembly, but the component is equally applicable to complexity Mimo system, SISO systems or similar system.For example, in mimo systems, in emitter 410, binary system data 420 It can be encoded to protect by using channel encoder 422, be interleaved using interleaver 424 to resist fade-out, with And mapped to improve reliability using mapper 426.The data of mapping can be separated by emitter (TX) beam-shaper 434 Into multiple layers for antenna port, and it can be used modulator 428A-B that these layer of OFDM is modulated into OFDM symbol.Modulation Device can be used fast fourier inverse transformation (IFFT) algorithm to calculate inverse discrete Fourier transformer inverse-discrete (IDFT) to generate modulated signal (it is used for the vector x) of each antenna port.Modulated signal can be converted into analog signal by D-A converter (DAC) 430A-B.Mould Intending signal can transmit via radio frequency (RF) emitter (Tx) 432A-B, and radio frequency sending set is configured as sending signal to emitter Antenna 440A-B, antenna is operable to transmit signal.Analog signal will comply with the path of referred to as channel 450.Physical layer may include Other component (not shown), such as go here and there and-simultaneously (S/P) converter, simultaneously-string (P/S) converter, cyclic prefix (CP) inserter and delete Except the component of device, protection band inserter and canceller and other needs.

The signal transmitted by channel 450 may suffer from noise 452 and interference 454.Noise and interference are represented as Addition 456 on channel signal, channel signal can be by the receiver antenna 490A-B and one or more radio frequencies of receiver 460 (RF) receiver (Rx) 482A-B is received.The channel signal combined with noise and interference can be by analog-digital converter (ADC) 480A-B It is converted into digital modulation signals.Demodulator 478A-B can be used to carry out OFDM demodulation for data signal.Quick Fu can be used in demodulator Found leaf transformation (FFT) algorithm to calculate DFT (DFT), (be used for each antenna port to produce demodulated signal Vector y).Channel estimator 462 can be used demodulated signal to estimate channel 450 and noise in the channel and interference occur.Letter Road estimator may include feedback generator or communicated with feedback generator that feedback generator can generate physics up-link and be total to Enjoy channel (PUSCH) feedback report, such as CQI (CQI) report, precoding matrix indicators (PMI) report or Transmission rank designator (RI) report.CQI can be used to assist MIMO transmission pattern.MIMO decoder 484 can be used to enter for demodulated signal Row combination, is carried out demapping using demapper 476, is deinterleaved using deinterleaver 474, and by channel decoder 472 are decoded, so as to generate binary system output data 470, binary system output data 470 can be made by other layers of receiving station With.

As illustrated in the flowchart of Figure 8, another example provides a kind of for adjusting nothing in coordinating multiple points (CoMP) system The method 500 of the receiver timing of line equipment.This method can be performed as the instruction on machine, wherein instruction be included in On a few computer-readable medium or a kind of non-transitory machinable medium.This method be included in wireless device from Multiple cooperative nodes in the coordination group of CoMP system receive the operation of multiple node specific reference signals (RS), wherein, coordinate Group includes at least two cooperative nodes, as indicated in block 510.Then carry out determining from multiple reception RS timing estimations synthesis reception RS When operation, multiple reception RS timing from the specific RS generations of multiple nodes, wherein, receive RS timings and represent from least two associations With the timing of node, as shown in frame 520.Next operation of this method can be at least partially based on synthesis to receive RS timing tune Whole receiver timing, as shown in frame 530.

The specific RS of node may include channel state information reference signals (CSI-RS).Adjusted receiver timing can be The time of the FFT (FFT) of the receiver processing received signal of wireless device.

In one embodiment, the operation of estimation synthesis reception RS timings can further comprise：RS timings are received for synthesis The earliest reception RS timings of selection.Synthesis receives RS timings can be byRepresent, wherein, τ_PDSCHIt is physics Downlink sharied signal channel (PDSCH) timing,It is the channel state information reference signals calculated of CoMP measurement groups (CSI-RS) each in timing, min () is minimum value function, and i is represent node in CoMP measurement groups just whole Number.

In another embodiment, the operation of estimation synthesis reception RS timings can further comprise：Selection is substantially in minimum Reception RS timings and maximum receptions RS timings between receiver RS regularly.Minimum reception RS timings may include from first The timing of the specific RS generations of first node received of cooperative nodes, and maximum reception RS timings may include from last The timing of the specific RS generations of the node finally received of cooperative nodes.In one example, can be by for cooperative nodes The combinations of the receptions RS timings of Reference Signal Received Power (RSRP) and the specific RS generations of node from cooperative nodes determines conjunction Into reception RS timings.In another example, synthesis receive RS timings can be byRepresent, wherein, τ_PDSCHIt is physical down link sharing channel (PDSCH) timing,It is the channel status calculated the letter of CoMP measurement groups Each in reference signal (CSI-RS) timing is ceased,It is CSI-RS antenna port Reference Signal Received Power (RSRP), i is the positive integer for representing the node in CoMP measurement groups, and f () is the monotonic function of its independent variable.

This method may also include wireless device and send the timing feedback that RS timings are received including synthesis to cooperative nodes. In another example, this method may also include wireless device by the reception RS including always being generated from the specific RS of node of cooperative nodes The timing feedback of timing sends cooperative nodes to.The specific RS of node may include master sync signal (PSS), auxiliary synchronous signals (SSS), Cell specific reference signal (CRS) or channel state information reference signals (CSI-RS).

As shown in the flow chart in Fig. 9, another example, which is provided, a kind of is used to making in coordinating multiple points (CoMP) system the Method of the timing of downlink (DL) transmission of one cooperative nodes relative to the downlink transmission synchronization of the second cooperative nodes 600.This method can be performed as the instruction on machine, wherein instruction be included at least one computer-readable medium or On a kind of non-transitory machinable medium.This method is included in the first cooperative nodes and receives timing feedback from wireless device Operation, wherein timing feedback includes receiving with reference to letter from the specific RS generations of the node of at least one cooperative nodes at least one Number (RS) timing, as shown in frame 610.Saved followed by being changed using timing feedback by adjusting timing in the first collaboration The operation of the downlink transmission timing of point, as indicated in block 620.

Timing feedback includes synthesis and receives RS timings or the reception RS timings of the first cooperative nodes.At least two can be come from from expression Multiple reception RS timing estimations synthesis of the timing of individual cooperative nodes receives RS timings.First cooperative nodes receive RS timings can be from The specific RS generations of node from the first cooperative nodes.These receive RS timings can be from the specific RS generations of multiple nodes.

In one example, synthesis receives RS timings and may include from the specific RS generations of node from the first cooperative nodes First cooperative nodes receive RS timings.Node specific reference signals include channel state information reference signals (CSI-RS).It is descending Link transmission includes data or physical down link sharing channel (PDSCH).The operation of modification downlink transmission timing can enter One step includes receiving RS timings based on synthesis or the first cooperative nodes receive RS timings, offsets for the descending of downlink transmission Fast fourier inverse transformation (IFFT) timing of link signal.This method may also include：First cooperative nodes are (for example, send association Same node) the selected cooperative nodes of the institute of the selection from multiple cooperative nodes.The specific RS of node from selected cooperative nodes can be by Wireless device is used for generating synchronous RS timings, and synchronization RS timings can be used for received data or received physical down chain The Timing Synchronization of road shared channel (PDSCH).First cooperative nodes it is transmittable selected cooperative nodes selection to wireless device. Synchronous RS timings can be used to adjust the receiver timing of the wireless device for received data or received PDSCH.This method It may also include：Before timing feedback is received, the first specific RS of cooperative nodes transmission node to wireless device.

Figure 10 shows example collaboration node 710A-B and exemplary wireless device 720 in coordinating multiple points (CoMP) system. Cooperative nodes may include grand node (for example, grand eNB) or low power nodes (for example, micro- eNB, micro, slight eNB, femto eNB, Or HeNB).

Wireless device 720 (for example, UE) can communicate with cooperative nodes 710A-B.Wireless device may include timing estimation equipment 718, the receiver timing for estimating the wireless device in coordinating multiple points (CoMP) system.Under timing estimation equipment may include Line link receiving module 722 and timing estimator 724.In certain embodiments, timing estimation equipment may include timing adjustment mould Block 726 and up-link (UL) delivery module 728.Wireless device may include to be configured to receive DL transmission information from cooperative nodes The transceiver of cooperative nodes is sent information to transmission UL.

Down-link reception module 722 can be configured as in wireless device from multiple collaborations in the coordination group of CoMP system Node receives multiple node specific reference signals (RS).Coordination group may include at least two cooperative nodes.Down-link reception mould Block be also configured to receive selected cooperative nodes selection.Selected cooperative nodes can be by the controller in core net or many Cooperative nodes among individual cooperative nodes are selected.The specific RS of node from selected cooperative nodes can be by wireless device For producing synchronous RS timings, and synchronization RS timings can be used for Timing Synchronization or adjust for received data or received thing Manage the receiver timing of the wireless device of downlink sharied signal channel (PDSCH).Timing estimator 724 can be configured as from multiple Receive the synthesis of RS timing estimations and receive RS timings, multiple reception RS are regularly from the specific RS generations of multiple nodes.Receiving RS timings can Represent the timing from least two cooperative nodes.The specific RS of node includes channel state information reference signals (CSI-RS). In one example, timing estimator, which can be configured as selection, to be used to synthesize the earliest reception RS timings for receiving RS timings.Synthesis Receiving RS timings can be byRepresent, wherein, τ_PDSCHIt is that physical down link sharing channel (PDSCH) is fixed When,Be CoMP measurement groups channel state information reference signals (CSI-RS) timing calculated in each, min () is minimum value function, and i is the positive integer for representing the node in CoMP measurement groups.In another example, timing estimation Device can be configured with synthesis and receive RS timings selection substantially in minimum reception RS timings and the reception RS timings of maximum Between receiver RS timing.In another example, timing estimator can be configured as from the reference letter for cooperative nodes The combinations of the receptions RS timings of number receiving power (RSRP) and specific RS generations of node from cooperative nodes determines synthesis reception RS timings.Synthesis receive RS timing byTo represent, wherein, τ_PDSCHIt is physical down chain Road shared channel (PDSCH) timing,It is the channel state information reference signals (CSI- calculated of CoMP measurement groups RS) each in timing,It is CSI-RS antenna ports Reference Signal Received Power (RSRP), i is to represent CoMP The positive integer of node in measurement group, and f () are the monotonic functions of its independent variable.

Timing adjustment module 726 can be configured as receiving RS timings based on synthesis adjusting receiver timing.Adjusted Receiver timing can be the time of the FFT (FFT) of the receiver processing received signal of wireless device.Should Time can represent the border of FFT windows.Up-link delivery module 728 can be configured as including synthesis to cooperative nodes transmission and connecing Receive RS timings or always from the timing feedback of the specific RS of node of the cooperative nodes reception RS timings generated.Wireless device can be wrapped Include user equipment (UE) and mobile station (MS).Wireless device, which can be configured to, is connected to WLAN (WLAN), radio individual area At least one in domain net (WPAN) and wireless wide area network (WWAN).Wireless device may include antenna, touch-sensitive display panel, raise one's voice Device, microphone, graphics processor, application processor, internal storage or nonvolatile memory port.

Each cooperative nodes 710A-B may include Timing Synchronization equipment 708A-B, in coordinating multiple points (CoMP) system Make the timing that the downlink (DL) of the first cooperative nodes is transmitted synchronous relative to the downlink transmission of the second cooperative nodes.It is fixed When synchronizer may include downlink transmission module 712A-B, extended receiver module 714A-B and timing modified module 716A-B.In one example, Timing Synchronization equipment may include selecting module (not shown).In another example, mould is selected Block can be comprised in the controller in core net.Cooperative nodes can be in the coordination group 740 of CoMP system, and via backhaul Link 750 is communicated.Back haul link may include X2 signalings or the backhaul chain connected via wired connection, wireless connection or optical fiber Line signaling.Communication between cooperative nodes may include that CoMP measures group information.

Extended receiver module 714A-B can be configured as receiving timing feedback from wireless device.Timing feedback may include At least one from the specific RS generations of the node of at least one cooperative nodes receives reference signal (RS) timing.Timing feedback can be wrapped Include synthesis and receive reference signal (RS) timing or the reception RS timings of the first cooperative nodes.Synthesis receives RS timings and can come from from expression The timing of at least two cooperative nodes multiple reception RS timing estimated, and receive RS regularly can be specific from multiple nodes RS is generated.First cooperative nodes receive RS timings can be from the specific RS generations of node from the first cooperative nodes.Timing modification mould Block 716A-B can be configured with timing feedback by adjusting timing in the modification downlink transmission timing of the first cooperative nodes. Node specific reference signals include channel state information reference signals (CSI-RS).Timing modified module is also configured to pass through Synthesis receives RS timings or cooperative nodes receive RS timings, offsets quick Fu of the down link signal for downlink transmission Vertical leaf inverse transformation (IFFT) timing.Downlink transmission module 712A-B can be configured to the specific RS of transmission node to wirelessly setting It is standby.Selecting module can be configured as the selected cooperative nodes of the institute of the selection from multiple cooperative nodes.From selected cooperative nodes The specific RS of node can be used for generating synchronous RS timings by wireless device, and synchronous RS timings can be used for received data or be connect Receive the Timing Synchronization of physical down link sharing channel (PDSCH).It is selected that downlink transmission module is also configured to transmission The selections of cooperative nodes is determined to wireless device.Synchronous RS timing can be used to adjust for received data or received PDSCH The receiver timing of wireless device.Cooperative nodes may include that grand node, low power nodes (LPN), grand evolved Node B are (grand ENB), micro- eNB, micro, slight eNB, femto eNB or family eNB (HeNB).

Figure 11 provides such as user equipment (UE), mobile station (MS), mobile wireless device, mobile communication equipment, flat board, hand Hold the example illustration of the wireless device of machine or other types of mobile wireless device etc.Wireless device may include one or more Antenna, the antenna configuration is node with such as grand node, low power nodes (LPN) etc, or such as base station (BS), drill Enter type Node B (eNB), Base Band Unit (BBU), remote radio heads (RRH), remote radio devices (RRE), relay station (RS), the transfer station of wireless device (RE) or other types of wireless wide area network (WWAN) access point etc is communicated.Nothing Line equipment, which can be configured to use, includes at least one of 3GPP LTE, WiMAX, high-speed packet access (HSPA), bluetooth and WiFi Wireless communication standard is communicated.Wireless device can be used to be communicated for the separated antenna of each wireless communication standard, Or communicated using the common antenna for multiple wireless communication standards.Wireless device can WLAN (WLAN), Communicated in wireless personal-area network (WPAN) and/or WWAN.

Figure 11 also provides the microphone available for the audio input from wireless device and output and one or more raised one's voice The diagram of device.Display screen can be liquid crystal display (LCD) screen or other types of display screen, such as Organic Light Emitting Diode (OLED) display.Display screen can be configured as touch-screen.Electric capacity, resistance or other types of touch can be used in touch-screen Screen technology.Application processor and graphics processor can be coupled to internal storage, to provide processing and display capabilities.It is non-volatile Port memory also can be used to provide a user data input/output intent option.Nonvolatile memory port can also be used for extension The store function of wireless device.Keyboard can be integrated with wireless device or be connected wirelessly to wireless device, extra to provide User inputs.Touch-screen can also be used to provide dummy keyboard.

Various technologies or its some aspect or part can be taken in such as floppy disk, CD-ROM, hard disk drive, non-transitory The program code realized in the tangible medium of computer-readable recording medium or any other machinable medium etc The form of (that is, instructing), wherein, when program code is loaded into machine (such as computer) and is performed by machine, the machine Device turns into the device for being used for realizing various technologies.In the case where program code is performed on programmable computers, computing device May include storage medium (including volatibility and nonvolatile memory and/or memory element) that processor, processor can be read, At least one input equipment and at least one output equipment.Volatibility and nonvolatile memory and/or memory element can be with It is RAM, EPROM, flash drive, CD-ROM drive, magnetic hard disk drives or other media for being used to store electronic data.Base station and nothing Line equipment may also include transceiver module, counter module, processing module and/or clock module or timer module.It can be achieved Or API (API), reusable controls can be used using one or more programs of various technologies described herein Etc..This class method can be communicated with high level procedural or object-oriented programming language to realize with computer system. However, if it is desired to if, this (these) program can be realized with assembler language or machine language.Under any circumstance, language Speech can be compiling or interpretative code, and is combined with hardware realization.

It should be appreciated that thering is many to be marked as module in the functional unit described in this manual, so as to more specific What them were emphasized in ground realizes independence.For example, module can be implemented as hardware circuit, including customization VLSI circuits OR gate battle array Row, the existing semiconductor of such as logic chip etc, transistor or other discrete components.Module can also be in such as field-programmable Realized in the programmable hardware device of gate array, programmable logic array, PLD etc..

Module can also be realized in the software for various types of computing devices.The identification module of executable code can example Such as include one or more physically or logically blocks of computer instruction, these computer instructions can for example be organized as object, mistake Journey or function.However, the executable code of identification module is not necessarily physically located together, but it may include to be stored in difference The different instruction of position, they are when being logically bonded together, including module and the purpose for realizing module.

In fact, the module of executable code can be single instruction perhaps MIMD, and it can even be distributed in some On different code segments, among distinct program, and across some memory devices.Similarly, peration data can be herein It is identified and is shown in module, and any suitable form can be implemented as and the number of any appropriate type is organized in According in structure.Peration data can be collected as individual data collection, or can be distributed in different positions, be included in different storages and set It is standby upper, and at least partly only can exist as the electronic signal in system or network.Module can be it is passive or active, Agency including being operable to perform required function.

" example " referred to through this specification is it is meant that the specific features, structure or the characteristic quilt that are described with reference to the example In at least one embodiment of the present invention.Therefore, the phrase occurred through this specification in various positions " shows at one In example " it is not necessarily all referring to same embodiment.

As it is used herein, for convenience, multiple projects, structural detail, element and/or material can be present in In common list.However, these lists should be interpreted as each member of list is respectively identified as separated sum Unique member.Therefore, when not indicating conversely, any one member in this list shall not be based only on they Equivalent on the fact that present in common group and be interpreted any other member in same list.In addition, the present invention Various embodiments and example may be mentioned together with the alternative for its various assemblies herein.It should be appreciated that this Class embodiment, example and alternative are not construed as mutual actual equivalent, and should be considered as the present invention Separated and independent expression.

In addition, described feature, structure or characteristic can phases in any suitable manner in one or more embodiments With reference to.In the following description, many concrete details are provided, the example of layout, distance, network example etc., so as to Thoroughly understand embodiments of the invention.However, those skilled in the relevant art are it will be recognized that the present invention can be in not described tool Implement in the case of one or more of body details or using other methods, component, layout etc..In other situations, Well-known structure, material or operation is not shown or described in detail, in order to avoid each aspect of the present invention is become obscure.

Although aforementioned exemplary is the explanation to the principle of the invention in one or more application-specifics, this area Those of ordinary skill can understand, creative work is not paid and principle and the design of the present invention is not departed from, it is possible to shape is made Formula, use and realize a variety of modifications in details.Therefore, the invention is intended to only limited by claims set out below.

Claims

1. one kind is used in coordinating multiple points（CoMP）User equipment is adjusted in configuration（UE）Receiver timing method, including：

In the UE multiple node specific reference signals are received from multiple nodes in the coordination group of the CoMP system（RS）, its In, the coordination group includes at least two nodes；

Produce the specific RS timings of multiple nodes by the antenna port reception at least two node；

From the average constant time lag of multiple reception RS timing estimations, wherein the average constant time lag includes emitter（TX）Delay, Propagation delay, receiver（RX）Delay or other processing delays；And

It is at least partially based on the receiver timing that the average constant time lag adjusts the UE.

2. according to the method described in claim 1, wherein, from multiple cooperative nodes receive multiple specific RS of node use with it is descending The associated channel state information reference signals of link transmission（CSI-RS）Antenna port or UE specific reference signals（UE is specific RS or UE-RS）Antenna port, and the downlink transmission includes data or physical down link sharing channel（PDSCH）.

3. according to the method described in claim 1, wherein, the specific RS of node include channel state information reference signals （CSI-RS）.

4. according to the method described in claim 1, wherein, the timing of the receiver that is adjusted is that the receiver processing of the UE is connect The FFT of the collection of letters number（FFT）Time.

5. according to the method described in claim 1, wherein, the specific RS of node include master sync signal（PSS）, auxiliary synchronous letter Number（SSS）, cell specific reference signal（CRS）, user equipment specific reference signals（UE specific RS or UE-RS）Or channel shape State information reference signal（CSI-RS）.

6. according to the method described in claim 1, wherein, the multiple node is cooperative nodes.

7. one kind is used in coordinating multiple points（CoMP）Make the downlink of the first cooperative nodes in configuration（DL）The timing phase of transmission The synchronous method of downlink transmission for the second cooperative nodes, including：

In first cooperative nodes from user equipment（UE）Timing feedback is received, wherein, timing feedback is included from least one The node specific reference signals of cooperative nodes（RS）At least one of generation receives RS timings；And

Using the timing feedback by adjusting timing in first cooperative nodes modification downlink transmission timing.

8. method according to claim 7, wherein, the timing feedback includes synthesis and receives RS timings or described first Cooperative nodes receive RS timing, wherein, by represent the timing from least two cooperative nodes multiple reception RS timing or Estimate the conjunction by receiving RS timings from the first cooperative nodes of the specific RS generations of node from first cooperative nodes Into reception RS timings, and reception RS timings are from the specific RS generations of the multiple node.

9. method according to claim 8, wherein, synthesis receives the day that RS timings represent at least two cooperative nodes Average retardation between the RS that line end mouth is received, wherein the average retardation includes emitter（TX）Delay, propagation delay, connect Receipts machine（RX）Delay or other processing delays.

10. method according to claim 7, wherein, the node specific reference signals are referred to including channel condition information Signal（CSI-RS）, and the downlink transmission include data or physical down link sharing channel（PDSCH）.

11. method according to claim 7, wherein, modification downlink transmission timing further comprises：

Receive RS timings or first cooperative nodes reception RS timings to offset for the downlink according to the synthesis The fast fourier inverse transformation of the down link signal of transmission（IFFT）Regularly, wherein offset IFFT timing include making it is described IFFT constant time lags shift to an earlier date.

12. method according to claim 7, is additionally included in before the reception timing feedback：

The selected cooperative nodes of institute are selected from multiple cooperative nodes in first cooperative nodes, wherein, selected from described The specific RS of node of cooperative nodes is used for generating synchronous RS timings by the UE, and the synchronous RS timings be used to be received Data or received physical down link sharing channel（PDSCH）Timing Synchronization；

The selection of the selected cooperative nodes is transmitted to the UE, wherein, the synchronous RS timings, which are used to adjustment, is used for institute Receive data or received PDSCH UE receiver timing；And

Use the channel state information reference signals associated with downlink transmission（CSI-RS）Antenna port or the specific ginsengs of UE Examine signal（UE specific RS or UE-RS）Antenna port, from first cooperative nodes to the specific RS of UE transmission nodes, and The downlink transmission includes data or physical down link sharing channel（PDSCH）.

13. at least one non-transitory machine readable media, including multiple instruction, the multiple instruction are suitable to be performed to realize Any one of claim 1-12 method.