Method and device for detecting preamble of wireless data frame

A method for detecting a preamble type of a wireless data frame, wherein the preamble has a synchronization (SYNC) field and a start frame delimiter (SFD) field the method comprising steps of

• receiving the wireless data frame;
• presuming that the received wireless data frame has a short type preamble;
• determining whether the wireless data frame has the short preamble;
• transmitting the wireless data frame to a MAC device when the wireless data
• frame has the short preamble;
• presuming that the received wireless data frame has a long type preamble if the wireless data frame does not have the short preamble;
• determining whether the wireless data frame has the long preamble;
• and
• transmitting the wireless data frame to the MAC device when the wireless data frame has the long preamble.

A device capable of detecting a preamble type of a wireless data frame, wherein the preamble has a synchronization (SYNC) field and a start frame delimiter (SFD) field the device comprising:

• a MAC (media access control) device;
• a receiver for receiving the wireless data frame;
• a demodulator/decoder module coupled to the receiver;
• a descrambler coupled to the demodulator/decoder module;
• a switching device coupled between the MAC device and the descrambler;
• and
• a preamble detector, coupled to the descrambler and the switching device, wherein the preamble detector outputs a control signal to the switching device for establishing a connection between the descrambler and the MAC device when the received wireless data frame has a short type preamble or a long type preamble.