LTE-U communication devices and methods for aperiodic beacon and reference signal transmission

Patent metadata

Field	Value
Publication number	US-10064064-B2
Application number	US-201514669366-A
Country	US
Kind code	B2
Filing date	Mar 26, 2015
Priority date	Jun 23, 2014
Publication date	Aug 28, 2018
Grant date	Aug 28, 2018

Abstract

An enhanced NodeB (eNB), user equipment (UE) and method of communicating using Long Term Evolution (LTE) licensed and unlicensed bands are generally described herein. The eNB may transmit a trigger signal to the UE. The trigger signal may be transmitted in the LTE unlicensed or licensed band and inform the UE of transmission of a reference signal from the eNB to the UE in the unlicensed band. The trigger signal may correspond to a single reference signal transmission or multiple periodic or consecutive reference signal transmissions. The trigger signal or a separate trigger signal may be used to inform the UE of a data transmission. The trigger signal may be transmitted at any point prior to or in the same subframe as the reference signal and the reference signal may be transmitted before, after or in the same subframe as the data.

First claim

What is claimed is:

1. An enhanced NodeB (eNB) comprising:
a transceiver configured to transmit signals to and receive signals from a user equipment (UE) on a carrier in a licensed band and a carrier in an unlicensed band; and
processing circuitry configured to:
cause the transceiver to transmit, to the UE, a trigger signal in one of the unlicensed or licensed band, the trigger signal configured to inform the UE of transmission of an aperiodic reference signal from the eNB to the UE in the unlicensed band using one of a Physical Downlink Control Channel (PDCCH), Enhanced Physical Downlink Control Channel (EPDCCH), Media Access Control Control Element (MAC-CE), or a Radio Resource Control (RRC) message in the one of the unlicensed or licensed band, wherein the one of the PDCCH or EPDCCH indicating the trigger signal is scrambled using a Radio Network Temporary Identifier (RNTI) that is different from a RNTI of a PDCCH or EPDCCH that does not indicate the trigger signal;
cause the transceiver to transmit, to the UE, the aperiodic reference signal in the unlicensed band in addition to transmitting periodic reference signals in one of the unlicensed or licensed band, the aperiodic reference signal including one of a cell-specific reference signal (CRS), a Channel Quality Indication (CQI), a channel state information reference signal (CSI-RS), or a Discovery Reference Signal (DRS); and
cause the transceiver to receive, from the UE, measurements of at least one of a channel quality and channel estimate based on the aperiodic reference signal,

wherein when the trigger signal corresponds to multiple aperiodic reference signals, the processing circuitry is configured to cause the transceiver to use an activation message to trigger the start of transmission of the aperiodic reference signals and use a deactivation message to trigger termination of transmission of the aperiodic reference signals, and the multiple aperiodic reference signals are transmitted periodically over a plurality of consecutive subframes.

2. The eNB of claim 1 , wherein:
the processing circuitry is configured to cause the transceiver to transmit the trigger signal N subframes prior to transmission of the aperiodic reference signal, where N is a non-negative integer.

3. The eNB of claim 1 , wherein the processing circuitry is configured to:
cause the transceiver to transmit, to the UE, a second trigger signal in one of the unlicensed or licensed band, the second trigger signal configured to inform the UE of a data transmission from the eNB to the UE in the unlicensed band, the data transmission able to be transmitted in a different subframe than the aperiodic reference signal; and
cause the transceiver to transmit, to the UE, the data transmission from the eNB to the UE in the unlicensed band.

4. The eNB of claim 3 , wherein the processing circuitry is configured to cause the transceiver to transmit at least one of:
the second trigger signal prior to the trigger signal,
the aperiodic reference signal prior to the data transmission, or
the aperiodic reference signal and the data transmission in the same subframe.

5. The eNB of claim 1 , wherein:
the trigger signal is further configured to inform the UE of a data transmission from the eNB to the UE in the unlicensed band, the data transmission able to be transmitted in a different subframe than the aperiodic reference signal.

6. The eNB of claim 1 , wherein the processing circuitry is further configured to:
cause the transceiver to transmit, to a plurality of UEs including the UE, scheduling information in one of the unlicensed or licensed band, the scheduling information configured to inform the UEs of at least one data transmission from the eNB to the UEs in the unlicensed band, wherein the scheduling information includes scheduling for a plurality of physical resource blocks using a single PDCCH or EPDCCH resource.

7. The eNB of claim 1 , wherein the processing circuitry is further configured to:
cause the transceiver to transmit, to a plurality of UEs including the UE, scheduling information in one of the unlicensed and licensed band, the scheduling information configured to inform the UEs of at least one data transmission from the eNB to the UEs in the unlicensed band, wherein the scheduling information includes Downlink Control Information (DCI) having an M-bit field, wherein each bit of the M-bit field represents a physical resource block in the unlicensed carrier.

8. The eNB of claim 1 , wherein the processing circuitry is further configured to:
cause the transceiver to transmit, to a plurality of UEs including the UE, scheduling information in one of the unlicensed and licensed band, the scheduling information configured to inform the UEs of at least one data transmission from the eNB to the UEs in the unlicensed band, wherein the scheduling information includes Downlink Control Information (DCI) having an M-bit field, where each bit of the M-bit field represents an individual UE.

9. The eNB of claim 1 , wherein the processing circuitry is further configured to:
cause the transceiver to transmit, to a plurality of UEs including the UE, scheduling information in one of the unlicensed or licensed band, the scheduling information configured to inform the UEs of at least one data transmission from the eNB to the UEs in the unlicensed band, wherein the scheduling information uses the EPDCCH having Downlink Control Information (DCI) scrambled using the RNTI configured to identify the plurality of UEs.

10. The eNB of claim 1 , wherein the trigger signal is configured to indicate to the UE transmission of the aperiodic reference signal on the carrier in the unlicensed band to permit the UE to take measurements of the aperiodic reference signal, even when the UE is unable to take measurements of non-aperiodic reference signals provided from the eNB on the carrier in the unlicensed band due to use of the carrier in the unlicensed band by the UE or WiFi devices proximate to the UE when the non-aperiodic reference signals are provided by the eNB, to permit coexistence between the UE and the WiFi devices.

11. The eNB of claim 1 , further comprising:
an antenna configured to transmit the trigger signal from the transceiver to the UE.

12. The eNB of claim 1 , wherein:
timing of transmission of the aperiodic reference signal with respect to the trigger signal is indicated in the trigger signal.

13. The eNB of claim 1 , wherein the processing circuitry is further configured to cause the transceiver to:
transmit to the UE a mix of trigger signals of which a first trigger signal corresponds to transmission of a single reference signal and a second trigger signal corresponds to transmission of multiple reference signals in different subframes for the UE.

14. The eNB of claim 1 , wherein the processing circuitry is further configured to:
select, as the RNTI to scramble the PDCCH or EPDCCH that indicates the trigger signal, a random-access RNTI.

15. The eNB of claim 1 , wherein the processing circuitry is further configured to:
select the RNTI to scramble the PDCCH or EPDCCH that indicates the trigger signal free from the use of bits in the PDCCH or EPDCCH to indicate the trigger signal.

16. A user equipment (UE) comprising:
a transceiver configured to transmit signals to and receive signals from an enhanced NodeB (eNB) on a carrier in a licensed band and a carrier in an unlicensed band; and
processing circuitry configured to:
cause the transceiver to receive, from the eNB, a trigger signal in one of the unlicensed or licensed band, the trigger signal configured to inf

Assignees

• Intel Ip Corp

Inventors

• Han Seunghee
• Bashar Shafi
• Niu Huaning
• Fwu Jong-Kae

Classifications

• H04W72/23 Primary

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04W72/1215

  for collaboration of different radio technologies · CPC title

• H04L5/0094

  Indication of how sub-channels of the path are allocated · CPC title

• H04L5/0057

  Physical resource allocation for CQI · CPC title

• H04L5/0073

  Allocation arrangements that take into account other cell interferences · CPC title