Method and Apparatus for Muting Signaling in a Wireless Communication Network
In one aspect, the present invention provides a simple method of signaling reference signal muting information to receiving radio equipment, such as items of user equipment (UEs). The reference signals may be positioning reference signals and/or cell-specific reference signals, for example. In one or more embodiments, the present invention proposes a general solution whereby the receiving radio equipment is informed not only on whether muting is used in general in a cell, but also the particular timing and formatting of such muting. Further, the contemplated method provides for the use of dynamic muting patterns, and thus avoids the need for statically defined muting patterns, and provides for coordinated muting control, across two or more network cells. In at least one embodiment, static or less dynamic aspects of the muting configuration is signaled via higher-layer signaling, while lower-layer signaling is used to signal more dynamic aspects of the muting configuration.
1 . A method of controlling the transmission of reference signals in a wireless communication network, said method comprising:
transmitting reference signals at recurring occasions, for use in making reference signal measurements at receiving radio equipment;
muting the reference signals in certain ones of the occasions, according to a muting configuration; and
transmitting muting configuration information indicating said muting configuration, to inform said receiving radio equipment of said muting configuration;
said muting configuration information including one or more of: a bandwidth parameter identifying the portion of reference signal bandwidth to which muting applies; a subframes parameter indicating the number of consecutive subframes within an occasion to which muting applies; and a muting occasion parameter indicating occasions to which muting applies.
2 . The method of claim 1 , wherein the reference signals are positioning reference signals transmitted at defined positioning occasions by at least one base station in the wireless communications network, and wherein said positioning reference signals are used by the receiving radio equipment in making positioning-related measurements.
3 . The method of claim 1 , wherein the receiving radio equipment comprises at least one of: one or more user equipments (UEs) associated with users of the wireless communication network; and one or more fixed nodes within the wireless communication network.
4 . The method of claim 1 , wherein said transmitting reference signals comprises transmitting reference signals from one or more base stations in the wireless communication network, each said base station associated with a respective cell.
5 . The method of claim 4 , further comprising determining the muting configuration on a per-cell basis.
6 . The method of claim 4 , wherein the one or more base stations comprise a plurality of base stations associated with respective ones in a plurality of associated cells, and further comprising determining the muting configuration cooperatively across the plurality of associated cells.
7 . The method of claim 4 , further comprising determining, at each base station, the muting configuration to be used by the base station based at least in part on control signaling received at the base station from a higher-layer node in the wireless communication network.
8 . The method of claim 7 , wherein the wireless communication network comprises a Long Term Evolution (LTE) network, or an LTE-Advanced network, and the base station comprises an eNodeB, and further comprising exchanging control signaling between the eNodeB and an E-SMLC that controls one or more aspects of the muting configuration of the base station.
9 . The method of claim 4 , further comprising determining, at each base station, the muting configuration to be used by the base station, based at least in part on exchanging muting configuration information or muting control signaling with one or more neighboring base stations.
10 . The method of claim 1 , wherein said transmitting muting configuration information comprises transmitting, via lower layer signaling, the muting occasion indicator as a flag or other indicator indicating whether muting will be used in an indicated or known occasion, and transmitting, via higher layer signaling, one or both of the bandwidth and subframes parameters, to complement the lower layer signaling of the muting occasion parameter, such that the receiving radio equipment is apprised of whether muting applies to a given occasion via the muting occasion parameter, and apprised of one or both the reference signal bandwidth and the number of consecutive subframes to which such muting applies, for that given occasion.
11 . The method of claim 10 , wherein said lower layer signaling comprises physical layer or Medium Access Control (MAC) layer protocol signaling.
12 . The method of claim 10 , wherein said higher layer signaling comprises Radio Resource Control (RRC) or LTE Positioning Protocol (LPP) signaling.
13 . The method of claim 1 , wherein said transmitting muting configuration information comprises transmitting the muting configuration information from a base station, via lower layer signaling.
14 . A base station for use in a wireless communication network that transmits reference signals, said base station comprising:
a transmitter configured to transmit reference signals at recurring occasions, for use in making reference signal measurements at receiving radio equipment;
a processing circuit operatively associated with the transmitter and configured to mute the reference signals in certain ones of the occasions, in accordance with a muting configuration; and
wherein said processing circuit is configured to transmit, via said transmitter, muting configuration information indicating said muting configuration, to inform said receiving radio equipment of said muting, and wherein the muting configuration information includes one or more of: a bandwidth parameter identifying the portion of reference signal bandwidth to which muting applies; a subframes parameter indicating the number of consecutive subframes within an occasion to which muting applies; and a muting occasion parameter indicating occasions to which muting applies.
15 . The base station of claim 14 , wherein the base station includes a core network communication interface for receiving muting control signaling via higher-layer signaling from another node in the wireless communication network, and wherein the processing circuit is configured to determine or otherwise set the muting configuration of the base station, based at least in part on said muting control signaling.
16 . The base station of claim 15 , wherein the wireless communication network comprises a Long Term Evolution (LTE) network, or an LTE-Advanced network, and the base station comprises an eNodeB, and wherein said muting control signaling received at the base station comprises signaling from an E-SMLC that controls one or more aspects of the muting configuration of the base station.
17 . The base station of claim 14 , wherein the base station is configured to transmit, via lower-layer signaling, the muting occasion indicator as a flag or other indicator indicating whether muting will be used in an indicated or known occasion, and to transmit, via higher-layer signaling, one or both of the bandwidth and subframes parameters, to complement the lower-layer signaling of the muting occasion parameter, such that the receiving radio equipment is apprised of whether muting applies to a given occasion via the muting occasion parameter, and apprised of one or both the reference signal bandwidth and the number of consecutive subframes to which such muting applies, for that given occasion.
18 . The base station of claim 14 , wherein the base station comprises an eNodeB, a home eNodeB, a pico base station, or a relay node.
19 . The base station of claim 14 , wherein the base station includes an inter-base-station communication interface and is configured to determine one or more aspects of the muting configuration cooperatively, with one or more neighboring base stations, based on exchanging inter-base-station signaling via the inter-base-station communication interface.
20 . The base station of claim 14 , wherein the base station includes a core network communication interface configured for communicating directly or indirectly with one or more core network nodes, including a positioning node, and wherein the base station is configured to receive signaling from the positioning node that sets or otherwise controls one or more aspects of the muting configuration of the base station.
21 . The base station of claim 14 , wherein the processing circuit is configured to autonomously determine the muting configuration to be used by the base station.
22 . The base station of claim 14 , wherein the reference signals are positioning reference signals transmitted at recurring positioning occasions.
23 . A positioning node for use with a wireless communication network, said positioning node comprising:
one or more processing circuits configured to determine a muting configuration used by one or more base stations for controlling muting of positioning reference signals transmitted at recurring positioning occasions by the one or more base stations; and
a communication interface operatively associated with the one or more processing circuits and configured to perform at least one of:
receive signaling from the one or more base stations, from which the one or more processing circuits determine the muting configuration of the one or more base stations, and send corresponding muting configuration information as higher-layer signaling for receipt by radio equipment receiving the positioning reference signals; and
send muting control signaling to the one or more base stations, to control reference signal muting by said one or more base stations, in accordance with the muting configuration.
24 . The positioning node of claim 23 , wherein the positioning node is configured to generate the muting configuration information to indicate when or how muting will be applied by the one or more base stations, for indicated or known positioning occasions, and to send at least a portion of the muting configuration information as higher-layer signaling, for transmission by the one or more base stations to the radio equipment receiving the positioning reference signals.
25 . The positioning node of claim 23 , wherein the one or more processing circuits are configured to control muting of the positioning reference signals in coordinated fashion across two or more cells of the radio access network, said two or more cells associated with said one or more base stations, and wherein the muting control signaling sent by the positioning node is configured to effect coordinated muting control across the two or more cells.
26 . The positioning node of claim 25 , wherein the one or more processing circuits are configured to coordinate, as across the two or more cells, at least one of the following: the timing or selection of which positioning occasions have muting applied to them; the positioning reference signal bandwidth to which muting is applied in one or more positioning occasions; and the number of consecutive subframes to which muting is applied within a given positioning occasion.
27 . A method at a positioning node, for use within a wireless communication network, said method comprising:
determining a muting configuration used by one or more base stations for controlling muting of positioning reference signals transmitted at recurring positioning occasions from the one or more base; and
further comprising at least one of:
receiving signaling from the one or more base stations, and determining the muting configuration of the one or more base stations from said received signaling, and sending corresponding muting configuration information as higher-layer signaling for receipt by radio equipment receiving the positioning reference signals; and
sending muting control signaling to the one or more base stations, to control reference signal muting by said one or more base stations, in accordance with the muting configuration.
28 . The method of claim 27 , further comprising generating the muting configuration information such that it indicates when or how muting will be applied by the one or more base stations, for indicated or known positioning occasions, and sending at least a portion of the muting configuration information as higher-layer signaling, for transmission by the one or more base stations to radio equipment receiving the positioning reference signals.
29 . The method of claim 27 , wherein said muting control signaling coordinates muting of the positioning reference signals across two or more cells of the wireless communication network, wherein the two or more cells are associated with the one or more base stations,
30 . The positioning node of claim 27 , wherein the muting control signaling is generated to coordinate at least one of the following across the two or more cells: the timing or selection of which positioning occasions have muting applied to them; the positioning reference signal bandwidth to which muting is applied in one or more positioning occasions; and the number of consecutive subframes to which muting is applied within a given positioning occasion.
31 . A method in a radio apparatus of controlling measurement of reference signals that are transmitted by a wireless communication network at recurring occasions, said method comprising:
receiving signaling from the wireless communication network that conveys one or more of the following muting parameters: a bandwidth parameter identifying the portion of reference signal bandwidth to which muting applies; a subframes parameter indicating the number of consecutive subframes within an occasion to which muting applies; and a muting occasion parameter indicating occasions to which muting applies; and
controlling reference signal measurement by the radio apparatus, in accordance with the received muting parameters.
32 . A radio apparatus comprising:
a receiver configured to receive reference signals transmitted from a wireless communication network at recurring occasions, and to receive signaling from the wireless communication network that conveys one or more of the following muting parameters that define a muting configuration used by the wireless communication network for muting the reference signals in one or more cells of the wireless communication network, said one or more muting parameters including at least one of: a bandwidth parameter identifying the portion of reference signal bandwidth to which muting applies; a subframes parameter indicating the number of consecutive subframes within an occasion to which muting applies; and a muting occasion parameter indicating occasions to which muting applies; and
one or more processing circuits that are operatively associated with the receiver and are configured to control reference signal measurement by the radio apparatus, in accordance with the received muting parameters.
33 . The method of claim 6 , wherein determining the muting configuration cooperatively across the plurality of associated cells comprises determining one or more muting patterns to be used across the plurality of associated cells.
34 . The method of claim 33 , further comprising transmitting muting occasion indicators from each base station in the plurality of base stations, in accordance with the one or more muting patterns.