Maximum Free Distance Binary to $M$-ary Convolutional Codes for Pseudo Chaotic Type Time Hopping PPM Impulse Radio UWB

The topic of spectral line suppression is of major interest in the design of pulse position modulated time hopping impulse radio ultra wideband communications systems. Previously pseudo-chaotic time hopping (PCTH) has been introduced to eliminate spectral lines and improving bit error rates (BER). In this letter, new binary to M-ary maximum free distance convolutional codes are introduced showing similar power spectral density characteristics as those obtained with PCTH and better BER for hard and soft decision decoding