Telecommunications apparatus and methods

Patent metadata

Field	Value
Publication number	US-2016128129-A1
Application number	US-201414895774-A
Country	US
Kind code	A1
Filing date	May 15, 2014
Priority date	Jun 13, 2013
Publication date	May 5, 2016
Grant date	—

Abstract

A wireless telecommunications system supports a DRX operating mode for communications between a base station and terminal device, which includes a regular repeating cycle of DRX inactive periods when the terminal device monitors a downlink channel from the base station and DRX active periods when the terminal device enters a power-saving mode not monitoring the downlink channel. The terminal device transmits uplink signaling, triggering subsequent downlink signaling, that may include acknowledgement signalling for a previous downlink transmission or an uplink transmission resources request. The base station receives the uplink signalling, determines time of an upcoming DRX inactive period for the terminal device, and delays transmitting downlink signalling responding to the uplink signalling until the upcoming DRX inactive period. The terminal device enters the power saving mode after transmitting the uplink signalling and exits the power saving mode for the DRX inactive period to monitor the downlink channel for downlink signalling.

First claim

What is claimed is:

1 . A method of operating a terminal device in a wireless telecommunications system which supports a discontinuous reception, DRX, operating mode, wherein the DRX mode comprises a repeating cycle of DRX inactive periods in which the terminal device monitors a downlink channel from a base station and DRX active periods during which the terminal device may enter a power saving mode and not monitor the downlink channel from the base station, the method comprising:
transmitting uplink signalling to the base station, wherein the uplink signalling comprises a trigger for downlink signalling on the downlink channel to be transmitted by the base station to the terminal device, wherein the downlink signalling is associated with and transmitted in response to the uplink signalling; and waiting until a DRX inactive period of the repeating cycle of DRX inactive periods before monitoring the downlink channel for the downlink signalling transmitted in response to the uplink signalling.

2 . The method of claim 1 , wherein the uplink signalling comprises acknowledgment signalling associated with a previous transmission from the base station to the terminal device and the downlink signalling is related to a retransmission of the previous transmission.

3 . The method of claim 1 , wherein the uplink signalling comprises a request for transmission resources and the downlink signalling is related to an allocation of transmission resources for the terminal device.

4 . The method of claim 1 , further comprising the terminal device making use of the power saving mode in a period between transmitting the uplink signalling and monitoring the downlink channel for the downlink signalling.

5 . The method of claim 1 , further comprising the terminal device transmitting a report on radio channel conditions to the base station in a time window defined relative to the DRX inactive period in which the terminal device monitors the downlink channel for the downlink signalling transmitted in response to the uplink signalling.

6 . The method of claim 5 , wherein the time window is associated with the beginning of the DRX inactive period in which the terminal device monitors the downlink channel for the downlink signalling transmitted in response to the uplink signalling.

7 . The method of claim 1 , wherein the repeating cycle of DRX inactive periods comprises DRX inactive periods repeating with a period associated with one or other of a DRX Cycle parameter and a DRX Short cycle parameter.

8 . The method of claim 7 , wherein the DRX Cycle parameter is an integer multiple of the DRX Short Cycle parameter.

9 . The method of claim 1 , further comprising transmitting further uplink signalling to the base station, wherein the further uplink signalling comprises a trigger for further downlink signalling on the downlink channel to be transmitted by the base station to the terminal device, and wherein the further uplink signalling is transmitted with a characteristic that is different from the first-mentioned uplink signalling, and wherein the method further comprises the terminal device monitoring the downlink channel for the further downlink signalling without waiting for a DRX inactive period of the repeating cycle of DRX inactive periods.

10 . A terminal device for use in a wireless telecommunications system which supports a discontinuous reception, DRX, operating mode, wherein the DRX mode comprises a repeating cycle of DRX inactive periods in which the terminal device monitors a downlink channel from a base station and DRX active periods during which the terminal device may enter a power saving mode and not monitor the downlink channel from the base station, wherein the terminal device comprises:
a transceiver unit configured to transmit uplink signalling to the base station of the wireless telecommunications system, wherein the uplink signalling comprises a trigger for downlink signalling on the downlink channel to be transmitted by the base station to the terminal device, wherein the downlink signalling is associated with and transmitted in response to the uplink signalling; and a processor unit configured to control the transceiver unit to wait until a DRX inactive period of the repeating cycle of DRX inactive periods before monitoring the downlink channel for the downlink signalling transmitted in response to the uplink signalling.

11 . The terminal device of claim 10 , wherein the uplink signalling comprises acknowledgment signalling associated with a previous transmission from the base station to the terminal device and the downlink signalling is related to a retransmission of the previous transmission.

12 . The terminal device of claim 10 , wherein the uplink signalling comprises a request for transmission resources and the downlink signalling is related to an allocation of transmission resources for the terminal device.

13 . The terminal device of claim 10 , wherein the controller unit is further configured to cause the terminal device to enter the power saving mode in a period between transmitting the uplink signalling and monitoring the downlink channel for the downlink signalling.

14 . The terminal device of claim 10 , wherein the transceiver unit is further configured to transmit a report on radio channel conditions to the base station in a time window defined relative to the DRX inactive period in which the terminal device is configured to monitor the downlink channel for the downlink signalling transmitted in response to the uplink signalling.

15 . The terminal device of claim 14 , wherein the time window is associated with the beginning of the DRX inactive period in which the terminal device monitors the downlink channel for the downlink signalling transmitted in response to the uplink signalling.

16 . The terminal device of claim 10 , wherein the repeating cycle of DRX inactive periods comprises DRX inactive periods repeating with a period associated with one or other of a DRX Cycle parameter and a DRX Short cycle parameter.

17 . The terminal device of claim 16 , wherein the DRX Cycle parameter is an integer multiple of the DRX Short Cycle parameter.

18 . The terminal device of claim 10 , wherein the transceiver is further configured to transmit further uplink signalling to the base station of the wireless telecommunications system, wherein the further uplink signalling comprises a trigger for further downlink signalling on the downlink channel to be transmitted by the base station to the terminal device, wherein the further downlink signalling is associated with and transmitted in response to the further uplink signalling; and wherein the further uplink signalling is transmitted with a characteristic that is different from the first-mentioned uplink signalling; and wherein the processor unit is further configured to control the transceiver unit to monitor the downlink channel for the further downlink signalling without waiting for a DRX inactive period of the repeating cycle of DRX inactive periods.

19 . A wireless telecommunications system comprising the terminal device of claim 10 and a base station.

Assignees

• Sony Corp

Inventors

• Kahtava Jussi
• Richards Derek John

Classifications

• H04W72/20

  Control channels or signalling for resource management · CPC title

• H04L1/1887

  Scheduling and prioritising arrangements · CPC title

• H04L1/1854

  Scheduling and prioritising arrangements · CPC title

• H04L5/0055 Primary

  Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861) · CPC title

• H04W52/0216 Primary

  using a pre-established activity schedule, e.g. traffic indication frame · CPC title