Medium access control protocol for OFDM wireless networks

• US 20060007885A1
• Filed: 09/08/2005
• Published: 01/12/2006
• Est. Priority Date: 02/06/1998
• Status: Active Grant

• Current Assignee: Greg Raleigh, Michael A. Pollack, Vincent K. Jones
• Original Assignee: Greg Raleigh, Michael A. Pollack, Vincent K. Jones
• Inventors: Raleigh, Gregory G., Pollack, Michael A., Jones, Vincent K.
• Granted Patent: US 7,551,578 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 5/023 Multiplexing of multicarrier modulation signals multicarrier modulation H04L27/2601

Abstract

A medium access contention protocol that is highly beneficial in wireless networks and particularly in wireless networks that employ a fixed minimum burst size such as OFDM wireless networks. In one embodiment, a MAC protocol is a demand-assigned protocol that maximizes utilization of the bus medium (the allocated frequency spectrum.) Each data communication device (DCD) in the network communicates with a central access point (AP). Multiple DCDs may request access from the AP in the same request access (RA) burst. Each of the multiple DCDs transmits its access request to the AP within a frequency domain channel in the RA burst that is orthogonal to the frequency domain channels used by the other DCDs requesting access. Each DCD includes channel training information in the access request burst to allow the AP and/or DCD to adapt to rapid variations in channel characteristics.

Claims

1. In a wireless network, a method for operating a data communication device comprising:

defining a burst length for time division multiple access communication; and

transmitting bursts having said fixed burst length from said data communication device, said bursts including information bursts carrying user payload data and no access request information and access bursts carrying access request information and no user payload data.

2. In a wireless network, a method for operating a central access point comprising:

defining a burst length for time division multiple access communication; and

receiving bursts having said fixed burst length from a plurality of data communication devices, said bursts including information bursts carrying user payload data and no access request information and access request bursts carrying access request information and no user payload data.

3. In a wireless network, apparatus for operating a data communication device comprising:

means for defining a burst length for time division multiple access communication; and

means for transmitting bursts having said fixed burst length from said data communication device, said bursts including information bursts carrying user payload data and no access request information and access bursts carrying access request information and no user payload data.