WO2018039986A1 - Procédés, unités centrales et unités réparties pour configuration de signaux de référence - Google Patents

Procédés, unités centrales et unités réparties pour configuration de signaux de référence Download PDF

Info

Publication number
WO2018039986A1
WO2018039986A1 PCT/CN2016/097571 CN2016097571W WO2018039986A1 WO 2018039986 A1 WO2018039986 A1 WO 2018039986A1 CN 2016097571 W CN2016097571 W CN 2016097571W WO 2018039986 A1 WO2018039986 A1 WO 2018039986A1
Authority
WO
WIPO (PCT)
Prior art keywords
configuration message
dus
transmitting
coverage
sub
Prior art date
Application number
PCT/CN2016/097571
Other languages
English (en)
Inventor
Yun HOU
Eddy Chiu
Original Assignee
Huizhou Tcl Mobile Communication Co.,Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Huizhou Tcl Mobile Communication Co.,Ltd filed Critical Huizhou Tcl Mobile Communication Co.,Ltd
Priority to CN201680085541.6A priority Critical patent/CN109075932B/zh
Priority to PCT/CN2016/097571 priority patent/WO2018039986A1/fr
Publication of WO2018039986A1 publication Critical patent/WO2018039986A1/fr

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/003—Arrangements for allocating sub-channels of the transmission path
    • H04L5/0048—Allocation of pilot signals, i.e. of signals known to the receiver
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/0091—Signaling for the administration of the divided path

Definitions

  • Embodiments of the present disclosure generally relate to communications, and in particular relate to methods, Central Units (CUs) , and Distributed Units (DUs) for Reference Signal (RS) configuration.
  • CUs Central Units
  • DUs Distributed Units
  • RS Reference Signal
  • CU/DU architecture Today, in order to meet the explosive growth of mobile service and data demands accompanying the rapid development of mobile communications, a CU/DU architecture has attracted wide attention.
  • An illustrative example of CU and DUs is given in FIG. 1, where a CU connects to and controls a number of DUs.
  • the DUs carry the lower layers of the air interface protocol stack and the CU is responsible for the upper layers for all DUs in a centralized way.
  • the CU can simply turn on/off the DUs to achieve more flexible DU deployments to reduce DU management overheads and facilitate inter-DU coordination, thus reducing the overall power consumption.
  • DU can also be referred to as transmission point (TP) , transmission and reception point (TRP) or Radio Remote Head (RRH) .
  • CU can also be referred to as dedicated building baseband unit (BBU) , centralized BBU, centralized radio access network (RAN) server, cloud server and virtual base station based on cloud architecture baseband pooling.
  • UE is generally connected to a nearby DU which is likely with good signal strength to obtain higher data throughput.
  • DU selection is needed either when UE initiates a new data transmission within coverage of the CU or switches from a current connected DU to another while maintaining a data connection. So, for DU selection in either case, the UE would need to evaluate candidate DUs with their signal strength/quality by measuring the RSs transmitted from the candidate DUs. Said differently, each DU needs to transmit a DU-specific RS for UE to distinguish and measure.
  • the CU can turn on/off certain DUs according to UE access conditions and tidal effects.
  • Each off-DU may enter an idle mode, in which it may not connect to any UE to transfer data, but may still need to send a discovery RS (DRS) for UEs to measure.
  • DRS is a temporally sparser version of Cell-specific RS (CRS) , while both DRS and CRS are always-on and statically allocated, thus causing excessive power consumption.
  • DRS or CRS has only 6 different RE-patterns that respectively correspond to different frequency offsets that are designed to avoid collision among time-frequency resources used by adjacent DUs for RS transmission.
  • some adjacent DUs may have to use the same RE-pattern, so that collision of time-frequency resources is likely to occur, leading to interferences.
  • an off-DU transmits DRS using an RE-pattern different from that used by adjacent DUs, it is possible that the adjacent DUs may use the same RE used by the DRS to transmit data, so the DRS may interfere with the data transmission.
  • Embodiments of the present disclosure provide methods, CUs, and DUs for RS configuration, to solve the issue of excessive power consumption and RS-to-RS, RS-to-Data interference, caused by off-DUs transmitting DRS in the prior art.
  • a method for RS configuration comprising: determining, by a CU, whether to turn on/off a DU within coverage of the CU, where the CU may connect to and control a plurality of such DUs, the CU may carry upper layers of an air interface protocol stack, and the DUs may carry the lower layers; and transmitting, by the CU, an RS configuration message to the DU, so that the DU may switch from stopping transmitting RS to transmitting a corresponding RS, or stop transmitting RS in response to the RS configuration message.
  • the RS configuration message used to instruct the DU to stop transmitting RS may comprise an information element (IE) used to control the DU to stop transmitting RS to enter an off-mode.
  • IE information element
  • the RS configuration message used to instruct the DU to transmit the corresponding RS may comprise associated RS parameters, including at least one of a transmission period, sub-frame offset, and RE-pattern.
  • the sub-frame offset may be used to indicate in which sub-frames of the transmission period the corresponding RS will be transmitted
  • the RE-pattern may be used to indicate how to map the corresponding RS to Resource Elements (REs) .
  • the RE-pattern may be CSI-RS-like or CRS-like.
  • the RS configuration message may contain a sub-frame offset that is mostly used by the all DUs currently transmitting RS.
  • Selecting the at least one Access-DU may comprise selecting the at least one Access-DU within the coverage at least based on a distribution of the DUs, to enable a transmission range of the RSs from the at least one Access-DU to cover the coverage of the CU.
  • Selecting the at least one Access-DU may further comprise: selecting the at least one Access-DU only among off-DUs.
  • Selecting the at least one Access-DU may comprise: selecting the at least one Access-DU within the coverage in response to a DU access request from a UE.
  • the method may further comprise: transmitting a list of the at least one Access-DU and associated RS parameters to the UE.
  • the first and second RS configuration messages either may comprise a sub-frame offset.
  • the sub-frame offset contained in the first RS configuration message may be the same as the sub-frame offset used before the first DU is connected to the at least one UE, and the sub-frame offset contained in the second RS configuration message may be the same as that in the first RS configuration message.
  • Determining whether to turn on/off the DU may comprise: determining, by the CU, whether to turn on the DU within the coverage of the CU based on UE switch information within the coverage, the switch information comprising at least information of a Source DU connected to the UE before switch and of a target DU connected to the UE after the switch.
  • Transmitting the RS configuration message to the DU may comprise: transmitting, by the CU, a candidate RS configuration message to the Source DU when the Source DU is not connected to any UE after the switch, and transmitting, by the CU, a serving RS configuration message to the Target DU when the Target DU is not connected to any UE before the switch.
  • the candidate RS configuration message and the serving RS configuration message either may comprise a sub-frame offset.
  • the sub-frame offsets contained in the candidate and serving RS configuration message may be the same as the sub-frame offsets used before the switch.
  • the CU may be a dedicated building baseband unit (BBU) , centralized BBU, centralized radio access network (RAN) server, cloud server or virtual base station based on cloud architecture baseband pooling.
  • the DU may be a transmission point (TP) , transmission and reception point (TRP) or Radio Remote Head (RRH) .
  • a method for RS configuration comprises: receiving, by a DU, an RS configuration message from a CU, where the CU may connect to and control a plurality of DUs, the CU may carry upper layers of an air interface protocol stack, and the DUs may carry the lower layers; switching, by the DU, from stopping transmitting RS to transmitting a corresponding RS, or stop transmitting RS in response to the RS configuration message.
  • the RS configuration message used to instruct the DU to stop transmitting RS may comprise an information element (IE) used to control the DU to stop transmitting RS to enter an off-mode.
  • IE information element
  • the RS configuration message used to instruct the DU to transmit the corresponding RS may comprise associated RS parameters, which may comprise at least one of a transmission period, sub-frame offset, and RE-pattern.
  • the sub-frame offset may be used to indicate in which sub-frames of the transmission period the corresponding RS will be transmitted, while the RE-pattern may be used to indicate how to map the corresponding RS to REs.
  • the RE-pattern may be CSI-RS-like or CRS-like.
  • the method may further comprise: transmitting, by the DU, a list of DUs to be measured and associated RS parameters to a UE, wherein the list of the DUs to be measured may comprise Access-DUs or the DU’s neighbor DUs.
  • a CU that comprises: a determination module configured to determine whether to turn on/off a DU within coverage of the CU, wherein the CU may connect to and control a plurality of DUs, the CU may carry upper layers of an air interface protocol stack, and the DUs may carry the lower layers; and a transmitting module configured to transmit an RS configuration message to the DU, so that the DU may switch from stopping transmitting RS to transmitting a corresponding RS, or stop transmitting RS in response to the RS configuration message.
  • the determination module may be configured to select at least one Access-DU within the coverage of the CU.
  • the transmitting module may be configured to transmit the RS configuration message to the at least one Access-DU in an off-mode, so that the Access-DU may start to transmit the corresponding RS.
  • the determination module may be configured to determine whether to turn on the DU within the coverage according to information of a first DU in the coverage, where the first DU may be a DU that is connected to at least one UE for the first time.
  • the transmitting module may be configured to transmit a first RS configuration message to the first DU, and transmitting a second RS configuration message to at least an off-DU among the neighbor DUs of the first DU.
  • the determination module may be configured to determine to turn on the DU within the coverage based on UE switch information in the coverage, wherein the UE switch information may comprise at least the information of a Source DU connected to the UE before switch and of a Target DU connected to the UE after the switch.
  • the transmitting module may be configured to transmit a candidate RS configuration message to the Source DU when the Source DU is not connected to any UE after the switch, and transmit a serving RS configuration message to the Target DU when the Target DU is not connected to any UE before the switch.
  • the determination module may be configured to determine whether to turn off the DU within the coverage based on information of DUs to be turned off, wherein the DUs to be turned off may comprise off-DU (s) (i.e., DU (s) set in the off-mode) , all neighbor non-serving DU (s) (i.e., DU (s) set in the non-serving mode) , and all serving DU(s) whose connected UEs all turn to an idle mode or are handed over to other CU’s coverage areas.
  • the transmitting module may be configured to transmit the RS configuration message to the DU to be turned off, to make the DU stop transmitting RS to enter the off-mode.
  • a DU that comprises: a receiving module configured to receive an RS configuration message from a CU, where the CU may connect to and control a plurality of DUs, the CU may carry upper layers of an air interface protocol stack, and the DUs may carry the lower layers; and a response module configured to switch from stopping transmitting RS to transmitting a corresponding RS, or stop transmitting RS in response to the RS configuration message.
  • the RS configuration message used to instruct the DU to stop transmitting RS may comprise an information element (IE) used to control the DU to stop transmitting RS to enter an off-mode.
  • IE information element
  • the RS configuration message used to instruct the DU to transmit the corresponding RS may comprise associated RS parameters, which may comprise at least one of a transmission period, sub-frame offset, and RE-pattern.
  • the sub-frame offset may be used to indicate in which sub-frames of the transmission period the corresponding RS will be transmitted, while the RE-pattern may be used to indicate how to map the corresponding RS to REs.
  • the RE-pattern may be CSI-RS-like or CRS-like.
  • the DU may further comprise a transmitting module configured to transmit a list of DUs to be measured and associated RS parameters to the UE, wherein the list of the DUs to be measured may comprise Access-DUs or the DU’s neighbor DUs.
  • a CU for RS configuration that comprises a processor and a transceiver coupled to the processor, where the processor may be configured to: determine whether to turn on/off a DU within coverage of the CU; and transmit via the transceiver an RS configuration message to the DU, so that the DU may switch from stopping transmitting RS to transmitting a corresponding RS or stop transmitting RS in response to the RS configuration message, wherein the CU may connect to and control a plurality of DUs, the CU may carry upper layers of an air interface protocol stack, while the DU may carry the lower layers.
  • the RS configuration message used to instruct the DU to stop transmitting RS may comprise an information element (IE) used to control the DU to stop transmitting RS to enter an off-mode.
  • IE information element
  • the RS configuration message used to instruct the DU to transmit the corresponding RS may comprise associated RS parameters, which may comprise at least one of a transmission period, sub-frame offset, and RE-pattern.
  • the sub-frame offset may be used to indicate in which sub-frames of the transmission period the corresponding RS will be transmitted, while the RE-pattern may be used to indicate how to map the corresponding RS to REs.
  • the RE-pattern may be CSI-RS-like or CRS-like.
  • the processor may be configured to: select at least one Access-DU within the coverage of the CU; and transmit via the transceiver the RS configuration message to the at least one Access-DU in an off-mode, so that the Access-DU may start to transmit the corresponding RS.
  • the RS configuration message may comprise a sub-frame offset that is mostly used by the all DUs currently transmitting RS.
  • the processor may be configured to select the at least one Access-DU within the coverage at least based on a distribution of the DUs, to enable a transmission range of the RSs from the at least one Access-DU to cover the coverage of the CU.
  • the processor may be configured to select the at least one Access-DU only among off-DUs.
  • the processor may be configured to select the at least one Access-DU within the coverage in response to a DU access request from a UE.
  • the processor may further be configured to transmit a list of the at least one Access-DU and associated RS parameters to the UE.
  • the processor may be configured to: determine whether to turn on the DU according to information of a first DU within the coverage, the first DU being a DU that is connected to at least one UE for the first time; and transmit via the transceiver a first RS configuration message to the first DU, and transmit a second RS configuration message to at least an off-DU among the neighbor DUs of the first DU.
  • the first and second RS configuration messages either may comprise a sub-frame offset.
  • the sub-frame offset contained in the first RS configuration message may be the same as the sub-frame offset used before the first DU is connected to the at least one UE, and the sub-frame offset contained in the second RS configuration message may be the same as that in the first RS configuration message.
  • the processor may be configured to: determine whether to turn on the DU based on UE switch information in the coverage, wherein the switch information may comprise at least the information of a Source DU connected to the UE before switch and of a Target DU connected to the UE after switch; and transmit via the transceiver a candidate RS configuration message to the Source DU when the Source DU is not connected to any UE after the switch, and transmit a serving RS configuration message to the Target DU when the Target DU is not connected to any UE before the switch.
  • the candidate RS configuration message and the serving RS configuration message either may comprise a sub-frame offset.
  • the sub-frame offsets contained in the candidate and serving RS configuration message may be the same as the sub-frame offsets used before the switch.
  • the processor may be configured to: determine whether to turn off the DU based on information of DUs to be turned off, wherein the DUs to be turned off may comprise off-DU (s) (i.e., DU (s) set in the off-mode) , all neighbor non-serving DU (s) (i.e., DU (s) in the non-serving mode) , and all serving DU (s) whose connected UEs all turn to an idle mode or are handed over to other CU’s coverage areas; and transmit via the transceiver the RS configuration message to the DU to be turned off, to make the DU stop transmitting RS to enter the off-mode.
  • off-DU i.e., DU (s) set in the off-mode
  • all neighbor non-serving DU (s) i.e., DU (s) in the non-serving mode
  • serving DU whose connected UEs all turn to an idle mode or are handed over to other CU’s coverage areas
  • the CU may be a dedicated building baseband unit (BBU) , centralized BBU, centralized radio access network (RAN) server, cloud server or virtual base station based on cloud architecture baseband pooling.
  • the DU may be a transmission point (TP) , transmission and reception point (TRP) or Radio Remote Head (RRH) .
  • a DU that comprises a processor and a transceiver coupled to the processor, the processor being configured to: receive via the transceiver an RS configuration message from a CU; and switch from stopping transmitting RS to transmitting a corresponding RS or stop transmitting RS in response to the RS configuration message, wherein the CU may connect to and control a plurality of DUs, the CU may carry upper layers of an air interface protocol stack, while the DUs may carry the lower layers.
  • the RS configuration message used to instruct the DU to stop transmitting RS may comprise an information element (IE) used to control the DU to stop transmitting RS to enter an off-mode.
  • IE information element
  • the RS configuration message used to instruct the DU to transmit the corresponding RS may comprise associated RS parameters, which may comprise at least one of a transmission period, sub-frame offset, and RE-pattern.
  • the sub-frame offset may be used to indicate in which sub-frames of the transmission period the corresponding RS will be transmitted, while the RE-pattern may be used to indicate how to map the corresponding RS to REs.
  • the RE-pattern may be CSI-RS-like or CRS-like.
  • the processor may further be configured to transmit a list of DUs to be measured and associated RS parameters to the UE, wherein the list of DUs to be measured may comprise Access-DUs or the DU’s neighbor DUs.
  • the CU can transmit an RS configuration message to a DU to enable the DU to switch between stopping transmitting RS and transmitting a corresponding RS, so that the DU may send RS only when needed.
  • stopping transmitting the RS can reduce the power consumption.
  • the DUs that have stopped transmitting RS need not to occupy the RE-patterns, so the total number of DUs competing for the RE-patterns can decrease, thus reducing the probability of collision of time-frequency resources among different DUs and also the RS-to-data interference.
  • FIG. 1 is a schematic diagram showing a CU/DU architecture.
  • FIG. 2 is a flowchart illustrating a first embodiment of a method for RS configuration according to the disclosure.
  • FIG. 3 is a flowchart illustrating a second embodiment of a method for RS configuration according to the disclosure.
  • FIG. 4 is a schematic diagram showing selection of Access-DUs in the second embodiment of the method for RS configuration.
  • FIG. 5 is a flowchart illustrating a third embodiment of a method for RS configuration according to the disclosure.
  • FIG. 6 is a flowchart illustrating a fourth embodiment of a method for RS configuration according to the disclosure.
  • FIG. 7 is a flowchart illustrating a fifth embodiment of a method for RS configuration according to the disclosure.
  • FIG. 8 is a schematic diagram showing switch of DU among three operating modes in a method for RS configuration according to an embodiment of the disclosure.
  • FIG. 9 is a flowchart illustrating a process by which a UE connects to a DU when there is not a direct connection between the UE and a CU in a method for RS configuration according to an embodiment of the disclosure.
  • FIG. 10 is a flowchart illustrating a process by which a UE connects to a DU when there is a direct connection between the UE and a CU in a method for RS configuration according to an embodiment of the disclosure.
  • FIG. 11 is a flowchart illustrating a sixth embodiment of a method for RS configuration according to the disclosure.
  • FIG. 12 is a flowchart illustrating a seventh embodiment of a method for RS configuration according to the disclosure.
  • FIG. 13 is a block diagram of a first embodiment of a CU according to the disclosure.
  • FIG. 14 is a block diagram of a second embodiment of a CU according to the disclosure.
  • FIG. 15 is a block diagram of a first embodiment of a DU according to the disclosure.
  • FIG. 16 is a block diagram of a second embodiment of a DU according to the disclosure.
  • FIG. 17 is a block diagram of a third embodiment of a DU according to the disclosure.
  • modules, units, circuits, or other components may be described or claimed as “configured to” perform a task or tasks.
  • “configured to” is used to connote structure by indicating that the modules/units/circuits/components include structure (e.g., circuitry) that performs those task or tasks during operation.
  • the modules/units/circuits/components can be said to be configured to perform the task even when the specified module/unit/circuit/component is not currently operational (e.g., is not on) .
  • the modules/units/circuits/components used with the “'configured to” language include hardware—for example, circuits, memory storing program instructions executable to implement the operation, etc.
  • module/unit/circuit/component is “configured to” perform one or more tasks is expressly intended not to invoke 35 U.S.C. ⁇ 112 (f) , for that module/unit/circuit/component.
  • “configured to” can include a generic structure (e.g., generic circuitry) that is manipulated by software and/or firmware (e.g., an FPGA or a general-purpose processor executing software) to operate in a manner that is capable of performing the task (s) at issue.
  • Configured to may also include adapting a manufacturing process (e.g., a semiconductor fabrication facility) to fabricate devices (e.g., integrated circuits) that are adapted to implement or perform one or more tasks.
  • the term “based on” describes one or more factors that affect a determination. This term does not foreclose additional factors that may affect the determination. That is, a determination may be solely based on those factors or based, at least in part, on those factors.
  • a determination may be solely based on those factors or based, at least in part, on those factors.
  • the method may be performed by a CU, including a central controller, such as a dedicated Building Baseband Unit (BBU) , centralized BBU, centralized radio access network (RAN) server, cloud server, or virtual base station based on cloud architecture baseband pool.
  • BBU Building Baseband Unit
  • RAN radio access network
  • the CU may carry upper layers of an air interface protocol stack, such as Packet Data Convergence Protocol (PDCP) , and the like.
  • PDCP Packet Data Convergence Protocol
  • the method may comprise the following blocks.
  • the CU may determine whether to turn on/off a DU within the coverage of the CU.
  • the DU can be a transmission point (TP) , transmission and reception point (TRP) or Radio Remote Head (RRH) .
  • the CU may base on UEs’a ccess demands to determine whether to turn on/off the DU.
  • the DUs that have been connected to UE (s) or have a greater chance of being connected to UE (s) , such as the neighbor DUs of the DU having been connected to a UE, may be turned on.
  • the DUs that are less likely to be connected to UE (s) may be turned off.
  • the CU may also turn on/off the DUs according to other requirements or conditions.
  • UE can be stationary or mobile from place to place, including, but not limited to, cellular phones, Personal Digital Assistants (PDA) , wireless modems, tablet computers, notebook computers, cordless phones, and so forth.
  • PDA Personal Digital Assistants
  • the CU may transmit an RS configuration message to the DU.
  • the operating modes of a DU can be divided into two, on and off, depending on whether it transmits RS.
  • a DU in the on-mode can transmit RS every sub-frame or every few sub-frames.
  • the DU may switch between the on and off modes. Specifically, the DU may switch from stopping transmitting RS to transmitting a corresponding RS, or conversely.
  • an on-DU i.e., DU in the on-mode
  • it can further be divided into a serving-DU and candidate-DU, i.e., DU in serving mode or candidate mode, depending on whether it connects to UE (s) for data transmission.
  • the frequency with which a serving-DU (i.e., connected to UE (s) ) transmits RS may be higher than a candidate-DU (i.e., not connected to UE (s) ) . That is, the RS transmission period of the serving-DU may be shorter than the candidate-DU.
  • a DU After a DU is turned on, it can respond to the RS configuration message to dynamically adjust the transmit RS parameters.
  • the CU may transmit the RS configuration message to only the DUs that need to start or stop transmitting RS or of which RS parameters change. Alternatively, the CU can transmit the RS configuration message to all DUs.
  • the CU can transmit an RS configuration message to a DU to enable the DU to switch between stopping transmitting RS and transmitting the corresponding RS, so that the DU may send RS only when needed, thus achieving event-triggered RS-transmission.
  • stopping transmitting RS can be more energy efficient.
  • the DUs that have stopped transmitting RS need not to occupy the RE-patterns, so the total number of DUs competing for the RE-patterns may decrease, thus reducing the probability of collision of time-frequency resources among different DUs and also the RS-to-data interference.
  • the RS configuration message may comprise RS parameter configuration signaling and turning-off signaling.
  • the turning-off signaling may be used to instruct the DU to stop transmitting RS, and may include a turning-off information element (IE) used to control the DU to stop transmitting RS and so enter an off-mode.
  • the RS parameter configuration signaling may be used to instruct the DU to transmit the corresponding RS, and may include the associated RS parameters.
  • the RS configuration message may comprise only one item of control signaling, or a plurality of items of control signaling.
  • the associated RS parameters may comprise at least one of a transmission period, sub-frame offset, and RE-pattern of the associated RS.
  • the sub-frame offset may be used to indicate in which sub-frames of the transmission period the corresponding RS will be transmitted, while the RE-pattern may be used to indicate how to map the corresponding RS to REs.
  • the RE-pattern can be CSI-RS-like or CRS-like.
  • the former refers to the mapping method similar to that used with Channel State Information (CSI) RS (CSI-RS)
  • CSI-RS Channel State Information
  • CRS Cell-specific RS
  • the mapping method will not be limited to the above and other suitable mapping methods can also be adopted.
  • both CRS/DRS and CSI-RS can be measured by UEs, and thus serve as the basis for DU selection.
  • the RE-pattern of CRS there are 6 possible RE-patterns depending on the result of the physical cell ID (PCI) of the BS mod 6.
  • the CRS is transmitted in each sub-frame of each Resource Block (RB) , while the transmission period of DRS is 40-160 sub-frames.
  • CSI-RS there are in total 40 possible RE locations for CSI-RS to use in an RB-pair. Out of the 40 possible RE locations, each CSI-RS may take 2, 4, or 8 REs depending on the number of antenna ports in use.
  • CSI-RS configurations there are up to 20 RE-patterns, or the so-called CSI-RS configurations.
  • which CSI configuration to use is determined by the antenna port to measure, so once the antenna port is determined, the RE patterns used for CSI-RS are fixed.
  • the transmission period of CSI-RS is typically 5-80 sub-frames.
  • the RS transmission period may refer to that of CRS/DRS or CSI-RS in the current standard, or may be set individually.
  • different sub-frame offsets can be set so that different DUs can transmit RSs in different sub-frames, thereby avoiding possible collision of time-frequency resources due to the limited types of RE-patterns, and so reducing the interference.
  • different sub-frame offsets may increase the total number of sub-frames the UE (s) is required to perform measurement, so that the power consumption may increase.
  • the types of RE-patterns can be increased, so that the probability that adjacent UEs need to use the same RE-pattern may drastically be reduced.
  • the adjacent DUs can use the same sub-frame offset and transmission period, hence the number of sub-frames the UE (s) is required to measure can be reduced, so does the power consumption.
  • different sub-frame offsets and/or transmission periods can also be used.
  • FIG. 3 a second embodiment of a method for RS configuration is depicted, which is based on the first embodiment of the RS configuration method and in which the DU is turned on in the form of Access-DUs.
  • the method is illustrated as being sequential. However, portions of the method may be performed in other orders or in parallel (e.g., simultaneously) .
  • the present embodiment is an extension of the first embodiment, so common contents therewith will not be detailed again.
  • the method under discussion may comprise the following blocks.
  • the CU may select at least one Access-DU within its coverage.
  • a UE hasn’ t may measure a set of DUs and select one of the DUs for connection.
  • the set of DUs that are provided for the UE that has not been connected to any DU to measure is called Access-DUs.
  • the CU may select the at least one Access-DU within the coverage at least based on a distribution of the DUs, to enable a transmission range of the RSs from the at least one Access-DU to cover the whole coverage of the CU, so that at any position within the coverage the UE needing DU access can detect the RS transmitted from at least one Access-DU.
  • An example is shown in FIG. 4, assuming all DUs within the coverage of the CU are not connected to any UEs, the three DUs marked out by rectangles of dashed lines are selected as Access-DUs, and they are in the on-mode and transmit RSs for UE (s) to measure, while the remaining DUs are in the off-mode.
  • the CU may select Access-DUs only among the off-DUs. Or, the on-DUs can also be included for selection.
  • the CU may transmit an RS configuration message to an Access-DU in the off-mode, so that the Access-DU may start to transmit a corresponding RS to enter the candidate mode.
  • the CU can also transmit an RS configuration message to an Access-DU in the on-mode, so the Access-DU can adjust the parameters of the transmit RS according to the RS configuration message.
  • the RS configuration message may comprise a sub-frame offset that is mostly used by the all DUs currently in the candidate mode and serving mode, so that the number of sub-frames the UE (s) is required to measure can be reduced.
  • FIG. 5 a third embodiment of a method for RS configuration is depicted, which is based on the first embodiment of the RS configuration method and in which the DU is turned on by obtaining information of a first DU.
  • the method is illustrated as being sequential. However, portions of the method may be performed in other orders or in parallel (e.g., simultaneously) .
  • the present embodiment is an extension of the first embodiment, so common contents therewith will not be detailed again.
  • the method under discussion may comprise the following blocks.
  • the CU may determine whether to turn on the DU within its coverage based on information of a first DU in the coverage.
  • the first DU may be a DU that is connected to at least one UE for the first time.
  • the first DU may be a candidate-DU before connected to the at least one UE.
  • the first DU can be a DU in the off-mode before connected to the at least one UE.
  • the CU may control the first DU to enter the serving mode, and turn on the neighbor DUs of the first DU. Understandably, the first DU may enter the serving mode at its discretion.
  • the CU may transmit a first RS configuration message to the first DU, and transmit a second RS configuration message to at least an off-DU among the neighbor DUs of the first DU.
  • the first DU may enter the serving mode in response to the first RS configuration message, while the off-DU among the neighbor DUs of the first DU may enter the candidate mode in response to the second RS configuration message.
  • the CU may not transmit the RS configuration message, or may transmit the RS configuration message to, for example, modify the RS parameters to match with the first DU.
  • the transmission period contained in the first RS configuration message may be smaller than that contained in the second RS configuration message.
  • the former may be an integral multiple of the latter.
  • the former may be the same as the latter.
  • the first and second RS configuration messages either may comprise a sub-frame offset.
  • the sub-frame offset contained in the first RS configuration message may be the same as the sub-frame offset used before the first DU is connected to the at least one UE (i.e. when the first DU is in the candidate mode)
  • the sub-frame offset contained in the second RS configuration message may be the same as that in the first RS configuration message, so that the number of sub-frames that the UE (s) is required to measure can be reduced.
  • FIG. 6 a fourth embodiment of a method for RS configuration is depicted, which is based on the first embodiment of the RS configuration method and in which the DU is turned on by obtaining the UE switch information between different DUs within the coverage.
  • the method is illustrated as being sequential. However, portions of the method may be performed in other orders or in parallel (e.g., simultaneously) .
  • the present embodiment is an extension of the first embodiment, so common contents therewith will not be detailed again.
  • the method under discussion may comprise the following blocks.
  • the CU may determine whether to turn on the DU within its coverage based on UE switch information in the coverage.
  • the switch information may contain at least the information of a Source DU to which the UE connects before switch and of a Target DU to which the UE connects after the switch.
  • the Target DU may be adjacent to the Source DU.
  • the CU may transmit a candidate RS configuration message to the Source DU, and if the Target DU is not connected to any UE before the switch, the CU may transmit a serving RS configuration message to the Target DU.
  • the Source DU may typically be in the serving mode before the UE switch, if the Source DU is not connected to any UE after the UE switch, then because it is adjacent to the Target DU, hence the CU may need to transmit a candidate RS configuration message to the Source DU to switch the Source DU from the serving mode to the candidate mode. Understandably, the Source DU may switch from the serving mode to the candidate mode at its discretion. In some embodiments, the CU may turn off the Source DU if the Source DU is not adjacent to the Target DU.
  • the Target DU would typically be in the serving mode after the UE switch, so if the Target DU is not connected to any UE (i.e. in the candidate mode) before the UE switch, the CU may need to transmit a serving RS configuration message to the Target DU to switch the Target DU from the candidate mode to the serving mode.
  • the CU may choose not to send the RS configuration message, or send the RS configuration message to modify the RS parameters of the Source DU and/or the Target DU.
  • the transmission period contained in the candidate RS configuration message may be greater than that contained in the serving RS configuration message. Further, the former may be an integral multiple of the latter. Alternatively, the transmission period contained in the candidate RS configuration message may be the same as that contained in the serving RS configuration message.
  • the candidate RS configuration message and the serving RS configuration message either may comprise a sub-frame offset.
  • the sub-frame offset contained in the candidate RS configuration message may be the same as the sub-frame offset used when the Source DU is in the serving mode (i.e. before the switch)
  • the sub-frame offset contained in the serving RS configuration message may be the same as that used when the Target DU is in the candidate mode.
  • a fifth embodiment of a method for RS configuration is depicted, which is based on the first embodiment of the method for RS configuration and in which the DU is turned off by obtaining the information of DUs to be turned off.
  • the method is illustrated as being sequential. However, portions of the method may be performed in other orders or in parallel (e.g., simultaneously) .
  • the present embodiment is an extension of the first embodiment, so common contents therewith will not be detailed again.
  • the method under discussion may comprise the following blocks.
  • the CU may determine whether to turn off the DU within its coverage based on the information of DU (s) to be turned off.
  • the DU (s) to be turned off may comprise DU (s) set in the off-mode (i.e., off-DU (s) , the candidate DU (s) of which all neighbor DUs are in the non-serving mode, and the serving DU (s) of which all connected UEs turn to the idle mode or are handed over to other CU’s coverage areas.
  • the CU may release the RS parameters occupied by the DU (s) to be turned off, that is, the same RS parameters used by the DU (s) to be turned off can be re-assigned to other DU (s) .
  • the CU may transmit an RS configuration message to the DU to be turned off.
  • the DU to be turned off may stop transmitting RS and enter the off-mode.
  • the CU may transmit an RS configuration message to the DU to enable the DU to switch among the three operating modes, of which the switch conditions are shown in FIG. 8.
  • the principles for determining which operating mode a DU is in can follow: a DU that is connected to UE (s) is in the serving mode, a DU that is not connected to any UE but is likely to build up a connection with a UE and thus needs to be measured by the UE is in the candidate mode, and the DU that doesn’ t meet the conditions of the candidate and serving modes, i.e., one that is not connected to any UE and needs not to be measured by any UE, is in the off-mode.
  • a serving DU i.e., a DU that is connected to UE (s) -hence in the serving mode
  • the serving DU will be turned off--hence enter the off-mode
  • the serving DU serves no UE and at least one connected UE switches to a neighbor DU, for example, part of the connected UE (s) go idle or handover and at least one UE switches to a neighbor DU, or all connected UE (s) switch to neighbor DU (s)
  • the serving DU will be turned to the candidate mode.
  • the candidate DU becomes a serving DU; on the other hand, if there is no neighbor DU in serving mode (case a) or the candidate DU is set as off-mode (case b) , the candidate DU turn to an off DU, herein, the candidate DU being set off as the off-mode means the candidate DU being deleted from the list of Access-DU (s) .
  • the off DU will become a candidate DU.
  • the DU may switch between the serving mode and the candidate mode under CU’s instruction or at its discretion.
  • the CU may not transmit the RS configuration message to the DU if the RS parameters used in the serving mode is the same as the RS parameters used in the candidate mode.
  • the DU (s) that needs to be measured by UE (s) may comprise Access-DUs and neighbor DUs of a serving DU.
  • the DU (s) that needs to be measured by UE (s) may comprise only the Access-DUs or the neighbor DUs of the serving DU.
  • the neighbor DUs of the serving DU may also be replaced with the DUs from which the distance to the first DU is smaller than a predetermined value.
  • the CU may also need to inform the UE of a list of DUs to be measured together with the associated RS parameters.
  • the above process of transmitting the list and the RS parameters can be divided into two cases, the distinction of which lies in whether it is the CU or the DU that is to transmit the list and the RS parameters.
  • the list of DUs to be measured may refer to a list of Access-DUs.
  • the list of DUs to be measured may be a list of the neighbor DUs of the currently connected DU.
  • FIG. 9 illustrates a specific process of building up a connection between a UE and a DU in the case there isn’ t a direction connection between the UE and a CU.
  • the process as shown are applicable to the cases, such as where the CU is not equipped with an antenna and thus is unable to set up a direction connection with the UE, or where UE has yet been connected to CU.
  • the CU may need to transmit the list of Access-DUs and the associated RS parameters to the DU, and the DU may then transmit the list and the RS parameters in system information to the UE.
  • the UE may read the system information to acquire the list and the associated RS parameters, and thus detect to select a DU and synchronize to the selected DU for random access, so the connection between the UE and the DU can be consequently completed.
  • FIG. 10 illustrates a specific process of building up a connection between a UE and a DU in the case where there is a direct connection between the UE and a CU.
  • the process is applicable to the cases where the UE remains a connected state with a CU, while posing an idle state with DU. So, the CU can select Access-DUs within its coverage in response to a DU access request from a UE, as shown in the figure, or may perform the selection at its own discretion without receiving any request from the UE.
  • the CU may then transmit directly the list of Access-DUs and the associated RS parameters to the UE, for example, by using the RRCConnectionReconfiguration Message in the LTE/LTE-A standard.
  • the UE may receive the list and the associated RS parameters, and thus detect to select a DU and synchronize to the selected DU for random access, so the connection between the UE and the DU can be consequently completed.
  • the random access only occurs between the UE and DU, because there already exists a connection between the UE and CU.
  • the CU and the DU connected to the UE may cooperatively work in a dual-connectivity or carrier aggregation mode.
  • FIG. 9 nor 10 shows the step by which the CU transmits the dedicated RS configuration message to the DU, because if the Access-DUs selected by the CU are all on-DUs, then the CU can choose not to transmit the RS configuration message to the Access-DUs. If the CU is to transmit the RS configuration message to the DU, this action should be performed before the CU or DU transmits the list of Access-DUs and the associated RS parameters to the UE.
  • the CU may also need to transmit, directly or through the selected DU, the list of DUs to be measured and the associated RS parameters to the UE, where the DUs to be measured refer to the neighbor DUs of the selected DU.
  • FIG. 11 illustrates a sixth embodiment of a method for RS configuration according to the disclosure, the method being performed by a DU that carries the lower layers of the air interface protocol stack.
  • the method is illustrated as being sequential. However, portions of the method may be performed in other orders or in parallel (e.g., simultaneously) .
  • it is yet decided how to divide the air interface protocol stack between the CU and DU, it has become a consensus that the DU should carry at least the physical layer.
  • the method may comprise the following blocks.
  • a DU may receive an RS configuration message from a CU.
  • the operating mode of a DU can be divided into two, on and off, depending on whether it transmits RS.
  • it can further be divided into a serving-DU and candidate-DU, i.e., DU in serving mode or candidate mode, depending on whether it connects to UE (s) for data transmission.
  • the frequency with which a DU in the serving mode (i.e., connected to UE (s) ) transmits RS may be higher than the DU in the candidate mode (i.e., not connected to UE (s) ) . That is, the RS transmission period of the serving-DU may be shorter than the candidate-DU.
  • the RS configuration message from the CU can be received through the interface configured between the CU and the DU.
  • the DU may switch from stopping transmitting RS to transmitting the corresponding RS or stop transmitting RS in response to the RS configuration message.
  • a DU When a DU is turned on, in response to the RS configuration message, it can stop transmitting RS, or dynamically adjust the transmit RS parameters, for example, switch between the candidate mode and the serving mode. When a DU is in the off-mode, it can start transmitting the corresponding RS in response to the RS configuration message.
  • the CU can transmit an RS configuration message to a DU to enable the DU to switch between stopping transmitting RS and transmitting the corresponding RS, so that the DU may send RS only when needed, thus achieving event-triggered RS-transmission.
  • stopping transmitting RS can be more energy efficient.
  • the DUs that have stopped transmitting RS need not to occupy the RE-patterns, so the total number of DUs competing for the RE-patterns may decrease, thus reducing the probability of collision of time-frequency resources among different DUs and also the RS-to-data interference.
  • a seventh embodiment of a method for RS configuration is depicted, which is based on the sixth embodiment of the RS configuration method and which further comprises the following blocks.
  • the DU may transmit a list of DUs to be measured and the associated RS parameters to the UE.
  • the DU may typically receive the list of DUs to be measured and the associated RS parameters from the CU.
  • the order of receiving the list and the RS parameters and receiving the RS configuration message from the CU is not limited.
  • the list of DUs to be measured may comprise Access-DUs and the neighbor DUs of the Access-DUs.
  • the list of DUs to be measured may refer to a list of Access-DUs.
  • the list of DUs to be measured may be a list of the neighbor DUs of the currently connected DU.
  • the CU may comprise a determination module 11 and a transmitting module 12.
  • the determination module 11 may be configured to determine whether to turn on/off a DU within coverage of the CU, where the CU may connect to and control a plurality of DUs, the CU may carry upper layers of an air interface protocol stack, and the DUs may carry the lower layers.
  • the transmitting module 12 may be configured to transmit an RS configuration message to the DU, so that the DU may switch from stopping transmitting RS to transmitting a corresponding RS or stop transmitting RS in response to the RS configuration message.
  • the determination module 11 may be configured to select at least one Access-DU within the coverage of the CU.
  • the transmitting module 12 may be configured to transmit the RS configuration message to the at least one Access-DU in an off-mode, so that the Access-DU may start to transmit the corresponding RS to enter a candidate mode.
  • the determination module 11 may be configured to determine whether to turn on the DU within the coverage according to information of a first DU within the coverage, the first DU being a DU that is connected to at least one UE for the first time.
  • the transmitting module 12 may be configured to transmit a first RS configuration message to the first DU, and transmit a second RS configuration message to at least an off DU among the neighbor DUs of the first DU.
  • the determination module 11 may be configured to determine whether to turn on the DU based on UE switch information within the coverage, wherein the switch information may comprise at least the information of a Source DU connected to the UE before switch and of a Target DU connected to the UE after the switch.
  • the transmitting module 12 may be configured to, when the Source DU is not connected to any UE after the switch, transmit a candidate RS configuration message to the Source DU, and, when the Target DU is not connected to any UE before the switch, transmit a serving RS configuration message to the Target DU.
  • the determination module 11 may be configured to determine whether to turn off the DU based on information of DU (s) to be turned off, wherein the DU (s) to be turned off may comprise off DU (s) , all neighbor non-serving DU (s) , and all serving DU (s) whose connected UEs all turn to idle mode or are handed over to other CU’s coverage areas.
  • the transmitting module 12 may be configured to transmit the RS configuration message to the DU to be turned off, to make the DU stop transmitting RS to enter the off-mode.
  • the CU may comprise a processor 110 and a transceiver 120 coupled to processor 110 via a bus.
  • the transceiver 120 may be configured to transmit and receive data, and serves an interface through which the CU communicates with other communication equipment.
  • Processor 110 may control operations of the CU, and can also be referred to as a Central Processing Unit (CPU) .
  • Processor 110 may be an integrated circuit chip with signal processing capabilities, such as a general purpose processor, Digital Signal Processor (DSP) , Application Specific Integrated Circuit (ASIC) , Field Programmable Gate Array (FPGA) , or any other programmable logic devices, discrete gates, transistor logic devices, or discrete hardware components.
  • DSP Digital Signal Processor
  • ASIC Application Specific Integrated Circuit
  • FPGA Field Programmable Gate Array
  • the general purpose processor may be a microprocessor or any conventional processor.
  • the CU may further comprise a memory storage (not shown) used to store the commands and data necessary for operations of the processor 110.
  • the memory storage can also store the data received by the transceiver 120.
  • Processor 110 may be configured to: determine whether to turn on/off a DU within coverage of the CU; and transmit via the transceiver 120 an RS configuration message to the DU, so that the DU may switch from stopping transmitting RS to transmitting a corresponding RS or stop transmitting RS in response to the RS configuration message.
  • the CU may connect to and control a plurality of DUs, the CU may carry upper layers of an air interface protocol stack, and the DUs may carry the lower layers.
  • the RS configuration message used to instruct the DU to stop transmitting RS may comprise an information element (IE) used to control the DU to stop transmitting RS to enter an off-mode.
  • IE information element
  • the RS configuration message used to instruct the DU to transmit the corresponding RS may comprise associated RS parameters, which may comprise at least one of a transmission period, sub-frame offset, and RE-pattern.
  • the sub-frame offset may be used to indicate in which sub-frames of the transmission period the corresponding RS will be transmitted, while the RE-pattern may be used to indicate how to map the corresponding RS to REs.
  • the RE-pattern may be CSI-RS-like or CRS-like.
  • Processor 110 may be configured to: select at least one Access-DU within the coverage of the CU; and transmit via the transceiver the RS configuration message to the at least one Access-DU in an off-mode, so that the Access-DU may start to transmit the corresponding RS to enter a candidate mode.
  • the RS configuration message may comprise a sub-frame offset that is mostly used by the all DUs currently in the candidate mode and serving mode.
  • processor 110 may be configured to select the at least one Access-DU within the coverage at least based on a distribution of the DUs, to enable a transmission range of the RS from the at least one Access-DU to cover the whole coverage of the CU.
  • processor 110 may be configured to select the at least one Access-DU only among off DUs.
  • processor 110 may be configured to select the at least one Access-DU within the coverage in response to a DU access request from a UE.
  • processor 110 may further be configured to transmit a list of the at least one Access-DU and associated RS parameters to the UE.
  • processor 110 may be configured to: determine whether to turn on the DU according to information of a first DU within the coverage, the first DU being a DU that is connected to at least one UE for the first time; and transmit via the transceiver a first RS configuration message to the first DU, and transmit a second RS configuration message to at least an off DU among the neighbor DUs of the first DU.
  • the first and second RS configuration messages either may comprise a sub-frame offset.
  • the sub-frame offset contained in the first RS configuration message may be the same as the sub-frame offset used before the first DU is connected to the at least one UE, and the sub-frame offset contained in the second RS configuration message may be the same as that in the first RS configuration message.
  • processor 110 may be configured to: determine whether to turn on the DU based on UE switch information within the coverage, the switch information comprising at least the information of a Source DU connected to the UE before switch and of a Target DU connected to the UE after the switch; and, when the Source DU is not connected to any UE after the switch, transmit via the transceiver a candidate RS configuration message to the Source DU, and, when the Target DU is not connected to any UE before the switch, transmit a serving RS configuration message to the Target DU.
  • the candidate RS configuration message and the serving RS configuration message either may comprise a sub-frame offset.
  • the sub-frame offsets contained in the candidate and serving RS configuration message may be the same as the sub-frame offsets used before the switch.
  • processor 110 may be configured to: determine whether to turn off the DU based on information of DU (s) to be closed, wherein the DU (s) to be closed may comprise off DU (s) , all neighbor non-serving DU (s) , and all serving DU (s) whose connected UEs all turn to an idle mode or are handed over to other CU’s coverage areas; and transmit via the transceiver the RS configuration message to the DU to be closed, to make the DU stop transmitting RS to enter the off-mode.
  • the CU may be a dedicated building baseband unit (BBU) , centralized BBU, centralized radio access network (RAN) server, cloud server or virtual base station based on cloud architecture baseband pooling.
  • the DU may be a transmission point (TP) , transmission and reception point (TRP) or Radio Remote Head (RRH) .
  • the DU may comprise a receiving module 21 and a response module 22.
  • the receiving module 21 may be configured to receive an RS configuration message from a CU.
  • the CU may connect to and control a plurality of DUs.
  • the DUs may carry the lower layers of the air interface protocol stack and the CU is responsible for the upper layers for all DUs in a centralized way.
  • the response module 22 may be configured to switch from stopping transmitting RS to transmitting the corresponding RS or stop transmitting RS in response to the RS configuration message.
  • FIG. 16 a second embodiment of a DU is depicted, which is based on the first embodiment DU and which further comprises a transmitting module 23.
  • the transmitting module 23 may be configured to transmit a list of DUs to be measured and associated RS parameters to the UE, wherein the list of DUs to be measured may comprise Access-DUs or the DU’s neighbor DUs.
  • the RS configuration message used to instruct the DU to stop transmitting RS may comprise an information element (IE) used to control the DU to stop transmitting RS to enter an off-mode.
  • IE information element
  • the RS configuration message used to instruct the DU to transmit the corresponding RS may comprise associated RS parameters, which may comprise at least one of a transmission period, sub-frame offset, and RE-pattern.
  • the sub-frame offset may be used to indicate in which sub-frames of the transmission period the corresponding RS will be transmitted, while the RE-pattern may be used to indicate how to map the corresponding RS to REs.
  • the RE-pattern may be CSI-RS-like or CRS-like.
  • a third embodiment of a DU may comprise a processor 210 and a transceiver 220 coupled to the processor 210 via a bus.
  • the transceiver 220 may be configured to transmit and receive data, and so serves as an interface through which the DU communicates with other communication equipment.
  • Processor 210 may control operations of the DU, and may also be referred to as a Central Processing Unit (CPU) .
  • Processor 210 may be an integrated circuit chip with signal processing capabilities, such as a general purpose processor, Digital Signal Processor (DSP) , Application Specific Integrated Circuit (ASIC) , Field Programmable Gate Array (FPGA) , or other programmable logic devices, discrete gates, transistor logic devices, or discrete hardware components.
  • DSP Digital Signal Processor
  • ASIC Application Specific Integrated Circuit
  • FPGA Field Programmable Gate Array
  • the general purpose processor may be a microprocessor or any conventional processor.
  • the DU may further comprise a memory storage (not shown) used to store the commands and data necessary for operations of processor 210.
  • the memory storage can also store the data received by the transceiver 220.
  • Processor 210 may be configured to receive via the transceiver 220 an RS configuration message from a CU, and switch from stopping transmitting RS to transmitting a corresponding RS or stop transmitting RS in response to the RS configuration message.
  • the CU may connect to and control a number of DUs.
  • the DUs may carry the lower layers of the air interface protocol stack and the CU is responsible for the upper layers for all DUs in a centralized way.
  • the RS configuration message used to instruct the DU to stop transmitting RS may comprise an information element (IE) used to control the DU to stop transmitting RS to enter an off-mode.
  • IE information element
  • the RS configuration message used to instruct the DU to transmit the corresponding RS may comprise associated RS parameters, which may comprise at least one of a transmission period, sub-frame offset, and RE-pattern.
  • the sub-frame offset may be used to indicate in which sub-frames of the transmission period the corresponding RS will be transmitted, while the RE-pattern may be used to indicate how to map the corresponding RS to REs.
  • the RE-pattern may be CSI-RS-like or CRS-like.
  • Processor 210 may further be configured to transmit a list of DUs to be measured and associated RS parameters to the UE, where the list of DUs to be measured may comprise Access-DUs or the DU’s neighbor DUs.
  • the CUs, DUs, and methods as discussed above may also be implemented in other forms. Rather, the CUs and DUs as described are merely illustrative, for example, the division of modules or units is based solely on logic functions, thus in actual implementations there may be other division methods, e.g., multiple units or components may be combined or integrated onto another system, or some features may be ignored or not executed.
  • mutual couplings, direct couplings, or communication connections as displayed or discussed may be achieved through some interfaces, devices, or units, and may be achieved electrically, mechanically, or in other forms.
  • Separated units as described may or may not be physically separated.
  • Components displayed as units may or may not be physical units, and may reside at one location or may be distributed to multiple networked units. Part or all of the units may be selectively adopted according to actual requirements to achieve objectives of the disclosure.
  • various functional units in the disclosure may be integrated into one processing unit, or may be presented as various physically separated units, and two or more units may be integrated into one.
  • the integrated units may be implemented by hardware, or may be implemented as software functional units.
  • the integrated units are implemented as software functional units and sold or used as standalone products, they can be stored in a computer readable storage medium.
  • Computer software products can be stored in a storage medium and can include multiple instructions enabling a computing device (e.g., a personal computer, a server, a network device, etc. ) or a processor to execute all or part of the methods as described in various embodiments.
  • the storage medium may include all kinds of media that can store program codes, such as a USB flash disk, mobile hard drive, Read-Only Memory (ROM) , Random Access Memory (RAM) , magnetic disk, or optical disk.

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

L'invention concerne un procédé de configuration de RS. Le procédé comprend les étapes consistant à faire déterminer, par une unité centrale (CU), s'il convient de mettre en marche/d'arrêter une unité répartie (DU) située dans la zone de couverture de la CU, la CU se connectant à et commandant une pluralité desdites DU, la CU portant des couches supérieures d'une pile de protocoles d'interface radio, et les DU portant les couches inférieures; et à faire envoyer, par la CU, un message de configuration de signaux de référence (RS) à la DU, de telle sorte que la DU passe d'un arrêt d'émission de RS à l'émission d'un RS correspondant ou cesse d'émettre des RS en réaction au message de configuration de RS. L'invention concerne également des CU et des DU associées.
PCT/CN2016/097571 2016-08-31 2016-08-31 Procédés, unités centrales et unités réparties pour configuration de signaux de référence WO2018039986A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN201680085541.6A CN109075932B (zh) 2016-08-31 2016-08-31 参考信号配置方法、中央单元及分布单元
PCT/CN2016/097571 WO2018039986A1 (fr) 2016-08-31 2016-08-31 Procédés, unités centrales et unités réparties pour configuration de signaux de référence

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2016/097571 WO2018039986A1 (fr) 2016-08-31 2016-08-31 Procédés, unités centrales et unités réparties pour configuration de signaux de référence

Publications (1)

Publication Number Publication Date
WO2018039986A1 true WO2018039986A1 (fr) 2018-03-08

Family

ID=61299831

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2016/097571 WO2018039986A1 (fr) 2016-08-31 2016-08-31 Procédés, unités centrales et unités réparties pour configuration de signaux de référence

Country Status (2)

Country Link
CN (1) CN109075932B (fr)
WO (1) WO2018039986A1 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111432415B (zh) * 2019-01-09 2022-05-17 华为技术有限公司 通信方法和装置
EP3923503A4 (fr) * 2019-03-12 2022-04-27 Huawei Technologies Co., Ltd. Procédé et appareil de gestion des interférences à distance
CN111836314A (zh) * 2019-04-22 2020-10-27 索尼公司 集中单元设备、用户设备、无线通信方法和存储介质

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103580742A (zh) * 2012-08-03 2014-02-12 上海贝尔股份有限公司 控制csi报告的方法及装置
CN104144475A (zh) * 2013-05-10 2014-11-12 华为技术有限公司 实现多点协作传输的方法、接入点与站点
US20150230214A1 (en) * 2012-09-25 2015-08-13 Panasonic Intellectual Property Corporation Of America Wireless communication method of signaling comp states, and transmission point and user equipment therefor
CN105684543A (zh) * 2013-05-10 2016-06-15 瑞典爱立信有限公司 承载配置信令

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102754458B (zh) * 2010-02-12 2015-09-16 黑莓有限公司 操作无线通信网络中的用户设备的方法、操作无线通信网络中的基站的方法、用户设备和基站
US8537911B2 (en) * 2011-02-21 2013-09-17 Motorola Mobility Llc Method and apparatus for reference signal processing in an orthogonal frequency division multiplexing communication system
US9014020B2 (en) * 2011-05-02 2015-04-21 Blackberry Limited Methods and systems of wireless communication with remote radio heads
JP6026415B2 (ja) * 2011-08-05 2016-11-16 パナソニック インテレクチュアル プロパティ コーポレーション オブ アメリカＰａｎａｓｏｎｉｃ Ｉｎｔｅｌｌｅｃｔｕａｌ Ｐｒｏｐｅｒｔｙ Ｃｏｒｐｏｒａｔｉｏｎ ｏｆ Ａｍｅｒｉｃａ 端末、送信装置、受信品質報告方法および受信方法
EP2727256A4 (fr) * 2011-08-08 2014-07-02 Huawei Tech Co Ltd Procédé et appareil destinés à des mesures de canaux pour une transmission multipoint coordonnée
WO2013100516A1 (fr) * 2011-12-26 2013-07-04 Samsung Electronics Co., Ltd. Appareil et procédé de transmission/réception d'informations d'émission de signal de référence dans un système de radiocommunication cellulaire utilisant une technique de transmission multipoint coordonnée
WO2013125900A1 (fr) * 2012-02-23 2013-08-29 엘지전자 주식회사 Procédé destiné à exécuter un transfert dans des systèmes c-ran et appareil associé
US9166718B2 (en) * 2012-05-11 2015-10-20 Intel Corporation Downlink control indication for a stand-alone new carrier type (NCT)
CN104469960B (zh) * 2013-09-25 2019-12-10 中兴通讯股份有限公司 调度配置方法与装置
US20150089382A1 (en) * 2013-09-26 2015-03-26 Wu-chi Feng Application context migration framework and protocol
US20170005770A1 (en) * 2013-12-26 2017-01-05 Sharp Kabushiki Kaisha Terminal device, base station device, and communication method
JP6298442B2 (ja) * 2015-12-28 2018-03-20 京セラ株式会社 基地局及びプロセッサ
JP6140323B2 (ja) * 2016-02-25 2017-05-31 京セラ株式会社 移動通信システム、基地局及び方法
EP3282782B1 (fr) * 2016-08-12 2019-11-06 Nokia Technologies Oy Transmission de signaux de référence de position dans un réseau de télécommunications sans fil

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103580742A (zh) * 2012-08-03 2014-02-12 上海贝尔股份有限公司 控制csi报告的方法及装置
US20150230214A1 (en) * 2012-09-25 2015-08-13 Panasonic Intellectual Property Corporation Of America Wireless communication method of signaling comp states, and transmission point and user equipment therefor
CN104144475A (zh) * 2013-05-10 2014-11-12 华为技术有限公司 实现多点协作传输的方法、接入点与站点
CN105684543A (zh) * 2013-05-10 2016-06-15 瑞典爱立信有限公司 承载配置信令

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PIERO CASTOLDI ET AL.: "What Role for Photonics in Xhaul Networks of 5G Systems?", ASIA COMMUNICATIONS AND PHOTONICS CONFERENCE 2015, 23 November 2015 (2015-11-23), pages 1 - 3, XP055466241 *

Also Published As

Publication number Publication date
CN109075932B (zh) 2022-03-01
CN109075932A (zh) 2018-12-21

Similar Documents

Publication Publication Date Title
US20210160741A1 (en) Method in a Base Station of a Communication System for Making a Handover Decision, Base Station, Computer Programs, and Computer Program Products
US10003992B2 (en) Macro cell assisted small cell discovery and resource activation
US10939306B2 (en) Method and apparatus for controlling beam transmission to grouped user equipment (UES)
US10085186B2 (en) Macro-cell assisted small cell discovery and resource activation
US20160345250A1 (en) Macro-cell assisted small cell discovery and resource activation
US10708025B2 (en) Managing reference signals in a wireless communication network
US10182393B2 (en) Macro-cell assisted small cell discovery and resource activation
JP2019533914A (ja) 通信方法及び通信装置
WO2018039986A1 (fr) Procédés, unités centrales et unités réparties pour configuration de signaux de référence
EP3501205B1 (fr) Gestion de mobilité basée sur une mesure de liaison montante
US20150230145A1 (en) Method and device for cell selection between heterogeneous networks in mobile communication system
US20220386222A1 (en) Autonomous Cell Measurements
CN115918206A (zh) 跨小区波束故障恢复
WO2021207990A1 (fr) Réseau cellulaire configurant sélectivement un intervalle de mesure sur la base d'un espacement de sous-porteuses
US11997509B2 (en) Methods for pathloss reference signal activation
WO2023065216A1 (fr) Conception de cssf pour équipement utilisateur à capacité de type needforgap
US20230077965A1 (en) Method and wireless network for supporting multiple measurement gaps in wireless network
CN117676876A (zh) 用于在特定模式下继续操作musim ue的方法和系统
CN116133024A (zh) 通信方法、装置、终端及存储介质

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16914552

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 16914552

Country of ref document: EP

Kind code of ref document: A1