An optimized digital modem architecture for VLSI implementation

Investigation into recently published research has uncovered a number of digital signal processing algorithms which have excellent performance characteristics and are well suited for VLSI implementation. The result of this investigative effort is an optimized modem signal processing architecture that is applicable to a variety of digital phase modulation schemes and that utilizes a combination of these techniques for signal generation, detection, and synchronization. The baseband signal processing functions which will be implemented in a VLSI gate array are described. The baseband digital signal processing architecture adopted in both the modulation and demodulation functions provides multirate capability by employing the principle of sample rate conversion. The demodulator signal processing features coherent adaptive matched filter detection and maximum likelihood symbol and carrier synchronization algorithms