Method and Apparatus for Muting Signaling in a Wireless Communication Network

Abstract

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.

Description

FIELD OF THE INVENTIONThe present invention generally relates to interference management in wireless communications networks, and particularly relates to controlling the muting of reference signals transmitted by one or more base stations in the network and signaling related muting configuration information.BACKGROUNDWireless communication networks use reference signal transmissions to support a variety of key functions. In this regard, a “reference” signal provides receiving radio equipment with some type of reference information—timing, frequency, phase, etc.—that enables certain measurements by the receiving equipment. For example, cell-specific reference signals, also referred to as common reference signals or CRSs provide receiving radio equipment with a basis for estimating propagation channel conditions. Other physical-layer reference signals include so called positioning reference signals or PRSs, which are particularly contemplated for newer, more capable networks, such as ...

AI Technical Summary

Benefits of technology

In one aspect, the present invention provides a simple method of signaling reference signal muting information to receiving radio equipment, such as UEs. (The reference signals may be, e.g., PRSs and / or CRSs.) 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 particular, 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. (In at least one embodiment, in cases where no muting bandwidth parameter is signaled, the receiving radio equipment is configured to assume that muting is applied over the entire reference signal transmission bandwidth.) Such information allows the receiving radio equipment—network node, UE, or other radio apparatus—to know exactly when and how reference signals are muted. In turn, that knowledge provides for improved accuracy in acquiring and measuring reference signals, and for reduced processing complexity through, for example, the elimination or reduction in blind searching.

In yet another embodiment, the present invention comprises a method and apparatus in a positioning node that is configured for use with a wireless communication network. The positioning node includes one or more processing circuits configured to determine a muting configuration used to control muting of positioning reference signals transmitted at recurring positioning occasions from one or more base stations in the wireless communication network. In one embodiment, the positioning node determines the muting configuration based on signaling received from the base station(s), i.e., the base stations inform the positioning node as to their muting configuration(s). In at least one such embodiment, the positioning node generates muting configuration information based on the signaling received from the base station(s), and it sends this muting configuration information as higher-layer signaling, to assist radio equipment with measuring the positioning reference signals transmitted from the base stations, in accordance with the muting configurations of those base stations.

In another embodiment, a base station is configured to generate the muting configuration and send it to a positioning node. In turn, the positioning node sends this information as assistance data—e.g., the positioning node sends positioning reference signal measurement assistance data to an item of user equipment. The BS then applies the generated muting configuration, i.e., it transmits or does not transmit reference signals accordingly. In this same embodiment and / or others, the base station is equipped with an interface over which the muting configuration is exchanged with other base stations, to provide for distributed coordination of muting configurations.

Problems solved by technology

GPS or A-GPS receivers, however, may not necessarily be available in all wireless terminals.

Furthermore, GPS is known to have a high failure incidence in indoor environments and urban canyons.

That, of course, increases the processing resources and the time needed for making PRS measurements, and tends to lower the accuracy of the results.

However, to date, the 3GPP standards do not specify how muting is to be implemented, nor do they specify signaling for communicating muting information to UEs or other receiving equipment that might be making use of the PRSs being transmitted by a given cell or a given cluster of neighboring cells.

While this approach offers certain advantages in terms of simplicity on the network side, it leaves receiving radio equipment with the same burdensome processing tasks, as said equipment has no knowledge of the random muting operations.

A further issue is the inability to know the optimal probabilities to use for making the muting decision, and the fact that such probabilities likely change in dependence on complex interrelationships between cells (varying geometry, etc.), and may even change depending upon times of day, etc.

However, this approach requires signaling the actual patterns or hard-coding them into the receiving equipment.

That latter approach may not be practical for some types of equipment.

Besides, the static nature of such mapping has its own disadvantages.

However, with the indicator set to TRUE, the UE still does not receive information indicating when and for which resource blocks (RBs) muting occurs, meaning that the UE still needs to blindly detect when PRS muting is used in each cell.

Images