Methods and apparatus for code division multiple access communication using code book that provides reduced peak-to-average power ratio

摘要

A method and apparatus are provided for generating a code book for use in a CDMA system. The code book comprises of a plurality of vectors that are used to encode user data. An amplitude and polarity for each vector in the code book are selected to provide a reduced peak-to-average power ratio. The amplitude values can be selected to provide a reduced peak-to-average power ratio while maintaining a desired average energy per chip. The desired energy per chip can be based on the energy per chip of a CDMA system having a lower order spreading factor. Performance can be further improved by employing a first code book under a first signal-to-noise ratio condition and a second code book under a second signal-to-noise ratio condition.

主权项

1. A method for generating a code book for use in a CDMA system, said code book comprised of a plurality of vectors, said method comprising:
selecting an amplitude and polarity value for each vector of said code book to provide a reduced peak-to-average power ratio for transmissions that include data transmissions comprising one or more data symbols, wherein each vector in said code book depends on transmitted user data, wherein each vector in said code book depends on transmitted user data by generating a vector v by multiplying said transmitted user data by a generator matrix and using said vector v in the formation of each of said vectors in said code book.