Techniques for performing efficient link adaptation in wireless personal networks

Patent metadata

Field	Value
Publication number	US-9319175-B2
Application number	US-200913141809-A
Country	US
Kind code	B2
Filing date	Nov 21, 2009
Priority date	Dec 24, 2008
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

A method ( 300 ) for performing link adaptation of wireless links in a wireless network. The method comprises generating a first enhanced link adaptation (ELA) information element ( 100 ) by the transmitter (S 310 ); sending the first ELA information element to at least one receiver (S 320 ); upon reception of a second ELA information element at the transmitter, determining optimal transmission parameters for the transmitter, wherein the second ELA information element is generated and sent by the at least one receiver in response to the first ELA information element (S 370 ).

First claim

What is claimed is:

1. A method for performing link adaptation of a wireless link between a transmitter and at least one receiver operable in a wireless personal area network (WPAN), comprising:
generating a first enhanced link adaptation (ELA) information element by the transmitter wherein the first ELA information element corresponds to a request mode;
sending, by the transmitter, the first ELA information element to the at least one receiver over the wireless link of the WPAN, wherein the first ELA information element is transmitted during a beacon period when immediate feedback is not requested and transmitted in a probe command frame if immediate feedback is requested;
generating a second ELA information element by the at least one receiver in response to the first ELA information element received by the at least one receiver, wherein the second ELA information element corresponds to a response mode;
sending by the at least one receiver the second ELA information element to the transmitter, wherein the second ELA information element is transmitted during a beacon period if immediate feedback is not requested and transmitted in a probe command frame if immediate feedback is requested; and
upon receiving the second ELA information element at the transmitter, determining optimal transmission parameters for the transmitter, the optimal transmission parameters including at least a data rate and transmission power level, based on requirements of at least one data stream to be transmitted, link quality information, and a number of correctly received packets, wherein the link quality information and the number of correctly received packets are included in the received second ELA information element.

2. The method of claim 1 , wherein generating the first ELA information element further comprises:
setting an element identification (ID) field of the ELA information element;
setting a length field to the length of the first ELA information element; and
setting subfields of at least one LINK field of the ELA information element.

3. The method of claim 2 , wherein setting the subfields of the at least one LINK field further comprises:
setting a Target Device Address (DevAddr) subfield to an address of the at least one receiver;
setting a control subfield to designate any one of an operation mode, a data stream mode, and an immediate feedback mode of the link field; and
setting at least one bit in a stream bitmap subfield.

4. The method of claim 3 , wherein the operation mode is set to the request mode, and the data stream mode and the immediate feedback mode are set according to a predetermined policy.

5. The method of claim 4 , wherein the first ELA information element is sent to the at least one receiver at a time scheduled according to the immediate feedback mode.

6. The method of claim 1 , wherein the second ELA information element includes an element ID field, a length field, and a link field, the link field including a Target DevAddr subfield, a control subfield, a stream bitmap subfield, a link quality information subfield, a non-acknowledged (Non-ACK) subfield.

7. The method of claim 6 , further comprising:
setting the control subfield;
setting the Target DevAddr subfield to an address of the transmitter;
including link quality information measured by the at least one receiver in the link quality information subfield; and
including at least a number of correctly received data packets in the Non-ACK subfield for each of the at least one data stream designated in the stream bitmap subfield.

8. The method of claim 7 , wherein the link quality information includes at least one of: an average signal-to-noise ratio (SNR) of a received signal and a received signal strength indicator (RSSI).

9. The method of claim 1 , wherein the requirements of the at least one data stream include at least one of guaranteed quality of service (QoS), type of the at least one data stream to be transmitted, and latency.

10. The method of claim 9 , further comprising computing a packet error rate (PER) threshold which is a maximum allowed PER to meet the requirements of the at least one data stream; and comparing the PER threshold to an estimated PER to determine the optimal transmission parameters.

11. The method of claim 9 , further comprising:
computing a packet error rate (PER) threshold which is a maximum allowed PER to meet the requirements of the at least one data stream;
computing a real PER to be a ratio of a number of incorrectly received packets to a number of transmitted packets; and
comparing the PER threshold to the real PER to determine the optimal transmission parameters.

12. The method of claim 1 , wherein when immediate feedback is not requested the receiver sends the ELA information element in a beacon period no later than a specified number of superframes.

13. A non-transitory computer readable medium having stored thereon computer executable code, when executed causing a processor to perform a process of link adaptation of a wireless link between a transmitter and at least one receiver, comprising:
generating a first enhanced link adaptation (ELA) information element by the transmitter wherein the first ELA information element corresponds to a request mode;
sending, by the transmitter, the first ELA information element to the at least one receiver over the wireless link of a wireless personal area network (WPAN), wherein the first ELA information element is transmitted during a beacon period when immediate feedback is not requested and transmitted in a probe command frame if immediate feedback is requested;
generating a second ELA information element by the at least one receiver in response to the first ELA information element received by the at least one receiver, wherein the second ELA information element corresponds to a response mode;
sending, by the at least one receiver, the second ELA information element to the transmitter, wherein the second ELA information element is transmitted during a beacon period if immediate feedback is not requested and transmitted in a probe command frame if immediate feedback is requested; and
upon receiving the second ELA information element at the transmitter, determining at least optimal transmission parameters for the transmitter, the optimal transmission parameters including at least a data rate and transmission power level, based on requirements of a data stream to be transmitted, link quality information, and a number of correctly received packets, wherein the link quality information and the number of correctly received packets are included in the received second ELA information element.

14. A device operable in a wireless personal area network (WPAN), the device comprising:
a processor;
a memory connected to the processor, wherein the memory contains instructions that, when executed by the processor, configure the device to generate a frame structure of an enhanced link adaptation (ELA) information element for transmission over a wireless link of the WPAN, wherein the ELA information element is used to determine optimal transmission parameters, the optimal transmission parameters including at least a data rate and transmission power level, and wherein the ELA information element includes:
an element identification field;
a length field for designating a size of the ELA information element; and
a plurality of link fields for providing link adaptation feedback mechanism between a transmitter and a receiver, wherein each of the plurality of link fields includes a Target device address (DevAddr) subfield designating an address of a target device, a control subfield for designa

Assignees

• Wang Dong
• Zhai Hongqiang
• Koninkl Philips Nv

Inventors

• Wang Dong
• Zhai Hongqiang

Classifications

• H04L1/0027

  Scheduling of signalling, e.g. occurrence thereof · CPC title

• H04L5/0007

  the frequencies being orthogonal, e.g. OFDM(A) or DMT · CPC title

• H04L1/0026 Primary

  Transmission of channel quality indication · CPC title

• H04L65/40 Primary

  Support for services or applications · CPC title

• H04W28/02

  Traffic management, e.g. flow control or congestion control · CPC title