Patent ID: 7551581

Claim:
A method for performing operations comprising: receiving, by a wireless communications device, a first protocol data unit over an air interface, wherein the first protocol data unit includes a first preamble to enable a receiver to synchronize, and which is received at a first modulation rate; a first header, following the first preamble, which is received at the first modulation rate; and the first service data unit, following the first header, which is received at a second modulation rate; and receiving, by the wireless communications device, a second protocol data unit over the air interface subsequent to said receiving the first protocol data unit and before expiration of an interframe space; wherein the second protocol data unit includes: a second preamble, which is received at the first modulation rate; a second header, following the second preamble, which is received at the first modulation rate; and a second service data unit, following the second header, which is received at a third modulation rate; wherein the second header further includes a data integrity field, the method further comprising determining whether the second header is valid using information in the data integrity field, and if the second header is not valid, evaluating at least one header-sized data segment subsequently received to attempt to find another possible header.