Selective demodulation of downlink traffic in wireless communication systems

• US 8,218,465 B1
• Filed: 01/10/2006
• Issued: 07/10/2012
• Est. Priority Date: 01/11/2005
• Status: Expired due to Fees

• Current Assignee: ZTE Corporation
• Original Assignee: ZTE Corporation
• Inventors: Hou, Jason, Cai, Sean, Chion, Mary
• Primary Examiner(s): Torres, Marcos
• Application Number:
  US11/329,917
• Time in Patent Office: 2,373 Days
• Field of Search: 370/342, 370/328, 370/311, 370/321, 370329-330, 370336-337, 370346-348, 370/395.4, 370/442, 370458-462, 370/338, 455/574, 4553431-3435, 455/450, 455/452.1
• US Class Current: 370/311
• CPC Class Codes: H04B 7/2643 using time-division multiple access [TDMA] H04B7/2615, H04B7/2618 take precedence
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Techniques of selective demodulation of downlink frames using a subscriber description segment or activity descriptor to identify one or more subscriber stations to which at least a portion of data placed in the downlink frame is addressed in wireless communication systems such as frame-based point-to-multipoint wireless communication systems. The described techniques can be used to reduce power consumption at each subscriber station and to elongate the battery time of mobile devices, especially in the bursty Internet data transmission. The subscriber station can use information in the subscriber description segment or activity descriptor to decide whether to turn off receiver power for the remainder of a received downlink frame.

Claims

1. A method for wireless communication, comprising:

transmitting, from a base station, a frame that comprises a downlink subframe and an uplink subframe, wherein the downlink subframe comprises a single description segment, a downlink map, and one or more data burst segments, wherein the single description segment is separate from the downlink map and appears in a beginning portion of the downlink subframe and in a subchannel location before the downlink map, the single description segment including one or more unique subscriber identifiers to identify one or more corresponding subscriber stations to which at least a portion of data placed in the downlink subframe is addressed, wherein the downlink map comprises information indicative of one or more data burst segment locations within the downlink subframe;

causing a subscriber station in communication with the base station to receive and decode the single description segment in the downlink subframe before decoding the downlink map and to determine whether the receiving subscriber station is identified by the single description segment as one of the subscriber stations to which at least one portion of the data placed in the downlink subframe is addressed;

when the receiving subscriber station is not identified in the single description segment, causing the receiving subscriber station to turn off a receiver in the receiving subscriber station for a remainder of the frame without further receiving and decoding the remainder of the frame; and

when the receiving subscriber station is identified in the single description segment, causing the receiving subscriber station to continue receiving and decoding a remaining part of the frame to recover data in the downlink subframe that is addressed to the receiving subscriber station.

2. A method as in claim 1, wherein the frame comprises a time division duplexing frame which includes the downlink subframe and the uplink subframe, and wherein the single description segment is placed in time prior to the uplink subframe.

3. A method as in claim 1, wherein the frame comprises a frequency division duplexing frame.

4. A method as in claim 1, wherein a subscriber identifier of the one or more unique subscriber identifiers is based on a connection identifier and a media access control identifier.

5. A method as in claim 1, wherein the base station and each subscriber station communicate with each other under an orthogonal frequency division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA) standard.

6. A method as in claim 5, further comprising:

causing a subscriber station to first sequentially decode a preamble and a frame control header in the downlink subframe; and

after decoding the frame control header, causing the subscriber station to decode the single description segment before decoding the downlink map.

7. A method as in claim 6, further comprising:

when the subscriber station is identified in the single description segment causing the subscriber station to decode the downlink map (DL-MAP) in the downlink subframe.

8. A method for wireless communication in a system where a base station produces a downlink frame that includes a description segment as part of a beginning portion of the downlink frame to identify one or more subscriber stations to which at least a portion of data placed in the downlink frame is addressed, the method comprising:

receiving at a subscriber station a downlink frame, the received downlink frame comprising a description segment, a downlink map, and data burst segments, wherein the description segment is separate from the downlink map and is arranged in a subchannel position prior to the downlink map in the downlink frame, wherein the downlink map comprises information indicative of data burst segment locations within the received downlink frame, and wherein the description segment of the received downlink frame includes subscriber station identification indices that uniquely identify corresponding subscriber stations and are respectively linked to entries within the downlink map;

causing the subscriber station in communication with the base station to first decode the description segment of the received downlink frame before decoding the downlink map and to determine whether the receiving subscriber station is identified by the description segment of the received downlink frame as one of the subscriber stations to which data placed in the received downlink frame is addressed; and

causing the subscriber station to selectively decode the downlink map based on information in the description segment of the received downlink frame.

9. A method as in claim 8, further comprising:

when the receiving subscriber station is identified in the description segment of the received downlink frame, causing the receiving subscriber station to continue receiving and decoding the remaining part of the received downlink frame to recover data in the received downlink frame that is addressed to the receiving subscriber station.

10. A method as in claim 8, further comprising:

when the receiving subscriber station is not identified in the description segment of the received downlink frame, causing the receiving subscriber station to turn off a receiver in the receiving subscriber station for a remainder of the received downlink frame without further receiving and decoding the remainder of the received downlink frame, wherein the remainder includes the downlink map of the received downlink frame.

11. A method as in claim 10, further comprising:

when the receiving subscriber station is identified in the description segment of the received downlink frame, causing the receiving subscriber station to continue receiving and decoding the remaining part of the received downlink frame to recover data in the received downlink frame that is addressed to the receiving subscriber station.

12. A wireless communication system, comprising:

a base station to wirelessly communicate with wireless subscriber stations;

a transmitter to transmit, from the base station, a frame that comprises a downlink subframe and an uplink subframe, wherein the downlink subframe comprises a single description segment, a downlink map, and one or more data burst segments, wherein the single description segment is separate from the downlink map and appears in a beginning portion of the downlink subframe, in a subchannel position before the downlink map, the single description segment including one or more unique subscriber identifiers to identify one or more corresponding subscriber stations to which at least a portion of data placed in the downlink subframe is addressed, wherein the downlink map comprises information indicative of one or more data burst segment locations within the downlink subframe;

a mechanism to control a subscriber station receiving the downlink subframe to first decode the single description segment and to determine whether the subscriber station is identified by the single description segment as one of the subscriber stations to which at least one portion of the data placed in the downlink subframe is addressed;

a mechanism to control the subscriber station to turn off a receiver in the subscriber station for a remainder of the frame without further receiving and decoding the remainder of the frame, when the subscriber station is not identified in the single description segment of the downlink subframe; and

a mechanism to control the subscriber station to continue receiving and decoding a remaining part of the frame to recover data in the received downlink subframe that is addressed to the receiving subscriber station, when the subscriber station is identified in the single description segment of the downlink subframe.

13. A system as in claim 12, wherein the frame comprises a time division duplexing frame which includes the downlink subframe and the uplink subframe, and wherein the single description segment is placed in time prior to the uplink subframe.

14. A system as in claim 12, wherein the frame comprises a frequency division duplexing frame.

15. A system as in claim 12, wherein the base station and each subscriber station communicate with each other under an orthogonal frequency division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA) standard.

16. A system as in claim 12, wherein a subscriber identifier of the one or more unique subscriber identifiers is based on a connection identifier and a media access control identifier.