Physical layer procedures for LTE in unlicensed spectrum

Abstract

The disclosure provides for control plane measurements in a wireless device. The wireless device may perform, on signals received over an unlicensed spectrum across multiple sub-frames, radio resource management (RRM) measurements of a cell. The wireless device may identify one or both of a first subset of the RRM measurements associated with a first subset of the sub-frames including opportunistic transmissions (i.e. before the transmission, clear channel assessment, CCA, is carried out) and a second subset of the RRM measurements associated with a second subset of the sub-frames including guaranteed transmissions (i.e. before the transmission, clear channel assessment, CCA, is not carried out). The wireless device may determine one or more RRM measurement values (e.g. RSSI, RSRQ) based on one or both of the first subset of the RRM measurements and the second subset of the RRM measurements. The wireless device may similarly perform radio link management (RLM) measurements and determine RLM measurement values based on the first and second subsets. The wireless device may also use timers (e.g. CCA timer, RLC timer) for uplink transmissions to detect radio link failures, RLFs.

Description

[0001] Cross References to Related Applications [0002] This patent application claims the benefit of U.S. Provisional Application Nos. 62 / 059,670, filed October 3, 2014, entitled "PHYSICAL LAYER PROCEDURES FOR LTE IN UNLICENSED SPECTRUM," and filed October 1, 2015, entitled "PHYSICAL LAYER PROCEDURES FOR LTE IN UNLICENSED SPECTRUM," US Patent Application No. 14 / 873,079, which is hereby expressly incorporated by reference in its entirety. Background technique [0003] In general, aspects of the present disclosure relate to wireless communications, and in particular, aspects of the present disclosure relate to physical layer procedures at wireless devices. [0004] Wireless communication networks are widely deployed to provide various communication services such as voice, video, packet data, messaging, broadcast, and so on. These wireless networks may be multiple-access networks capable of supporting multiple users by sharing available network resources. Examples of such mul...

AI Technical Summary

Problems solved by technology

When the reference signal is lost, the UE may not be able to measure the eNodeB's downlink channel correctly

Missing or inaccurate measurements can cause additional problems with radio resource monitoring, radio link monitoring, and radio link failure detection

With the foregoing in mind, it should be appreciated that there are significant problems and disadvantages associated with the operation of wireless devices in shared and unlicensed spectrum

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