Backward-compatible long training sequences for wireless communication networks

A wireless communications device, comprising:

• a signal generator that generates an extended long training sequence;
• and
• an Inverse Fourier Transformer operatively coupled to the signal generator,
• wherein the Inverse Fourier Transformer processes the extended long training sequence from the signal generator and provides an optimal extended long training sequence with a minimal peak-to-average ratio, and
• wherein at least the optimal extended long training sequence is carried by a greater number of subcarriers than a standard wireless networking configuration for an Orthogonal Frequency Division Multiplexing scheme,
• wherein the optimal extended long training sequence is carried by exactly 56 active sub-carriers, and
• wherein the optimal extended long training sequence is represented by encodings for indexed sub-carriers −28 to +28, excluding indexed sub-carrier 0 which is set to zero, as follows:
• Sub-carrier
• −28
• −27
• −26
• −25
• −24
• −23
• −22
• Encoding
• +1
• +1
• +1
• +1
• −1
• −1
• +1
• Sub-carrier
• −14
• −13
• −12
• −11
• −10
• −9
• −8
• Encoding
• +1
• +1
• +1
• −1
• −1
• +1
• +1
• Sub-carrier
• 1
• 2
• 3
• 4
• 5
• 6
• 7
• Encoding
• +1
• −1
• −1
• +1
• +1
• −1
• +1
• Sub-carrier
• 15
• 16
• 17
• 18
• 19
• 20
• 21
• Encoding
• +1
• +1
• −1
• −1
• +1
• −1
• +1
• Sub-carrier
• −21
• −20
• −19
• −18
• −17
• −16
• −15
• Encoding
• +1
• −1
• +1
• −1
• +1
• +1
• +1
• Sub-carrier
• −7
• −6
• −5
• −4
• −3
• −2
• −1
• Encoding
• −1
• +1
• −1
• +1
• +1
• +1
• +1
• Sub-carrier
• 8
• 9
• 10
• 11
• 12
• 13
• 14
• Encoding
• −1
• +1
• −1
• −1
• −1
• −1
• −1
• Sub-carrier
• 22
• 23
• 24
• 25
• 26
• 27
• 28
• Encoding
• −1
• +1
• +1
• +1
• +1
• −1
• −1.