Walsh code


Also found in: Dictionary, Wikipedia.
Related to Walsh code: OVSF

Walsh code

Also known as "Walsh-Hadamard code," it is an algorithm that generates statistically unique sets of numbers for use in encryption and cellular communications. Known as "pseudo-random noise codes," Walsh codes are used in direct sequence spread spectrum (DSSS) systems such as Qualcomm's CDMA. They are also used in frequency hopping spread spectrum (FHSS) systems to select the target frequency for the next hop. See CDMA.

Walsh Code Algorithm

          (a', b') = (a+b, a-b)
Mentioned in ?
References in periodicals archive ?
2288 Mbps chip rate, an IS-95 forward link pilot channel and 16 orthogonal channels with 0 to 63 selectable Walsh codes.
This is a great improvement compared to the system applying Walsh Codes, which need to cancel N-1 users in the worst case.
This relationship holds for both the Hadamard numbering of the Walsh codes in IS-95 and CDMA2000 as well as the bit-reversed Hadamard code numbering used in wideband CDMA (W-CDMA).
OVSF codes are orthogonal codes similar to the Walsh codes used in 2G CDMA (IS-95) BTS.
Spreading function using Walsh codes and Quasi Orthogonal