Signaling format for WLANS

• US 7,751,429 B2
• Filed: 10/26/2004
• Issued: 07/06/2010
• Est. Priority Date: 02/13/2004
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Kondylis, George, Trachewsky, Jason A., Bagchi, Amit G.
• Primary Examiner(s): Edouard; Patrick N
• Assistant Examiner(s): PHUONG, DAI
• Application Number:
  US10/973,611
• Publication Number:
  US 20050181800A1
• Time in Patent Office: 2,079 Days
• Field of Search: 455/436, 455/439, 455/450, 455/452.1, 455/452.2, 455/453, 370/252, 370/329, 370/330, 370/331, 370/333
• US Class Current: 370/465
• CPC Class Codes: H04L 5/1438 Negotiation of transmission parameters prior to communication modified according to link quality H04L1/0001
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A method for wireless communication begins by determining whether legacy devices are within a proximal region of the wireless communication. The method continues, when at least one legacy device is within the proximal region, formatting a frame to include: a legacy preamble; a signal field; an extended preamble; at least one additional signal field; at least one service field; an inter frame gap; and a data field.

Claims

1. A method for wireless communication in a network that includes non-legacy devices, the method comprises:

determining whether a legacy device is within a proximal region of the wireless communication;

when the legacy device is within the proximal region, formatting a frame to include;

a first portion having;

a legacy preamble; and

a signal field;

a second portion having;

an extended preamble; and

at least one additional signal field; and

a third portion that includes at least one of;

at least one service field;

an inter frame gap; and

a data field;

wherein the first portion is readable by the legacy device in accordance with a legacy frame format;

wherein the second portion is unreadable by the legacy device in accordance with the legacy frame format;

and wherein the second portion is readable by the non-legacy devices in accordance with a non-legacy frame format.

2. The method of claim 1 further comprises:

when the legacy device is not within the proximal region, formatting a frame to include;

a native preamble;

at least one signal field;

at least one service field;

an inter frame gap; and

a data field.

3. The method of claim 2, wherein the at least one signal field comprises at least one of:

rate/mode information;

length information;

last data unit in the frame indication;

data unit acknowledgment requirement; and

error checking capability.

4. The method of claim 2 further comprises at least one of:

coding the at least one signal field using a rate ½

convolutional code;

coding the at least one signal field using an outer Reed-Solomon block code and an inner coding of the rate ½

convolutional code; and

coding the at least one signal field using a rate ⅓

convolutional code with a constraint length of six.

5. The method of claim 2 further comprises at least one of:

for a legacy channel, utilizing a quadrature phase shift keying (QPSK) for the at least one signal field; and

for a wide bandwidth channel;

utilizing QPSK for subcarriers of a first portion of the wide bandwidth channel, wherein the first portion has a bandwidth corresponding to the legacy channel; and

replicating the first portion for a second portion of the wide bandwidth channel.

6. The method of claim 3, wherein the rate/mode information comprises at least one of:

implicit number of transmit antennas;

implicit channel width; and

physical layer data rate.

7. The method of claim 3, wherein the length information comprises at least one of:

bytes of PSDU [PLCP (physical layer convergence procedure) Service Data Unit].

8. The method of claim 1, wherein the signal field comprises at least one of:

rate/mode information;

length information;

last data unit in the frame indication; and

number of antennas.

9. A radio frequency (RF) transmitter for use in communicating with legacy devices that operate in accordance with a first frame format and non-legacy devices that communicate in accordance with a second frame format, the RF transmitter comprises:

a baseband processing module operably coupled to convert outbound data into an outbound symbol stream; and

a transmitter section operably coupled to convert the outbound symbol stream into outbound RF signals, wherein the baseband processing module is operably coupled to;

determine whether at least one of the legacy devices is within a proximal region of the wireless communication;

when at least one of the legacy devices is within the proximal region, format a frame in a third frame format that includes;

a first portion having;

a legacy preamble; and

a signal field;

a second portion having;

an extended preamble; and

at least one additional signal field; and

a third portion that includes at least one of;

at least one service field;

an inter frame gap; and

a data field

wherein the first portion is readable by the at least one legacy device in accordance with the first frame format;

wherein the second portion is unreadable by the at least one legacy device in accordance with the first frame format;

and wherein the second portion is readable by the non-legacy devices, in accordance with the second frame format.

10. The RF transmitter of claim 9, wherein the baseband processing module is further operably coupled to:

when the at least one of the legacy devices is not within the proximal region, format a frame in the second frame format to include;

a native preamble;

at least one signal field;

at least one service field;

an inter frame gap; and

a data field.

11. The RF transmitter of claim 10, wherein the at least one signal field comprises at least one of:

rate/mode information;

length information;

last data unit in the frame indication;

data unit acknowledgment requirement; and

error checking capability.

12. The RF transmitter of claim 10, wherein the baseband processing module is further operably coupled to, at least one of:

code the at least one signal field using a rate ½

convolutional code;

code the at least one signal field using an outer Reed-Solomon block code and an inner coding of the rate ½

convolutional code; and

code the at least one signal field using a rate ⅓

convolutional code with a constraint length of six.

13. The RF transmitter of claim 10, wherein the baseband processing module is further operably coupled to, at least one of:

for a legacy channel, utilize a quadrature phase shift keying (QPSK) for the at least one signal field; and

for a wide bandwidth channel;

utilize QPSK for subcarriers of a first portion of the wide bandwidth channel, wherein the first portion has a bandwidth corresponding to the legacy channel; and

replicate the first portion for a second portion of the wide bandwidth channel.

14. The RF transmitter of claim 11, wherein the rate/mode information comprises at least one of:

implicit number of transmit antennas;

implicit channel width; and

physical layer data rate.

15. The RF transmitter of claim 11, wherein the length information comprises at least one of:

bytes of PSDU [PLCP (physical layer convergence procedure) Service Data Unit].

16. The RF transmitter of claim 9, wherein the signal field comprises at least one of:

rate/mode information;

length information;

last data unit in the frame indication; and

number of antennas.