Patent ID: 7881361
Filing Date: 2011-02-01
Classification: H04B,H04L

Abstract:
1. An apparatus for transmitting a direct sequence spread spectrum signal, including: a data transformation process transforming an input data signal into a plurality of digital data streams based, at least in part, on a data rate vector to form a plurality of channels; a logic circuit for each channel in communication with the data transformation process to form a plurality of analog data signals corresponding to the plurality of channels, each logic circuit spreading the digital data stream for the corresponding channel based, at least in part, on a processing gain vector defining a proportional relationship between a chip rate and the data rate vector for the corresponding channel; a combining process for each channel in communication with the logic circuit for the corresponding channel to form a plurality of modulated subcarrier data signals corresponding to the plurality of channels, each combining process combining the analog data signal for the corresponding channel with a subcarrier frequency defined, at least in part, by a frequency separation vector associated with adjacent subcarrier frequencies; and an amplifier for each channel in communication with the combining process for the corresponding channel to form a plurality of scaled subcarrier data signals corresponding to the plurality of channels, each amplifier amplifying the modulated subcarrier data signal for the corresponding channel based, at least in part, on a bit energy vector; wherein a value for at least one of the data rate vector, processing gain vector, frequency separation vector, and bit energy vector for at least one channel is different from another value for the corresponding data rate vector, processing gain vector, frequency separation vector, or bit energy vector for another channel, and wherein the frequency separation vector contains at least one element with a value equal to or less than an element with the minimum value in the data rate vector, thereby causing overlap among subcarrier spectra to produce spectral shaping.