Flexible prototyping platform for synthesis of Constant Envelope Spread Spectrum (CE-SS) waveforms
This paper deals with CE-SS (Constant-Envelope Spread Spectrum) signals, focusing on a novel generation technique based upon using digital processing blocks to drive a frequency modulator with a random sequence. The system described herein allows for flexibility in achieving a variety of user defined goal spectra. The foundation upon which this work is built was laid by Callegari et al. [2]-[5] who introduced a novel synthesis procedure for 'non-stationary' modulations [2]. This novel synthesis technique uses an iterative algorithm to arrive at an output spectrum which is a good approximation to a user-defined goal spectrum. The architecture which this paper details uses programmable logic to tune the system parameters in striving towards user defined goal spectra. The architecture can generate CE-SS waveforms whose spectra match those which the aforementioned algorithm deems achievable.
spread spectrum ce-ss (constant-envelope spread spectrum) waveforms spectrum shaping