The Thue-Morse sequence (TMS), the "parity check" sequence formed on a normal binary counter, has been proposed as a vehicle for comma-free synchronizatin of binary counters. This note reports further work on the TMS as a vehicle for commafree synchronization of binary counters. Specifically, we present a new synchronization algorithm and a way to implement the algorithm via PSK encoding/DPSK decoding, and we examine and comment on the TMS/BPSK spectrum.

This paper presents a new type of digital system which makes use of adaptive delta-modulation for input digitization and is particularly suited to the hardware implementation of small, low power, programmable digital filters. An experimental prototype was built which demonstrated a finite impulse response (FIR) digital filter. This filter has no requirement for hardware multipliers and has a significant reduction in input sample storage capacity when compared to equivalent pulse code modulation (PCM) filters. Quantitative as well as qualitative results show that this new filter is especially useful with voice inputs.

The use of polarity coincidence correlation techniques can allow efficient use of digital logic elements for binary differential phase-shift-key demodulation. For the case of sinusoidal signals in the presence of additive Gaussian noise it is shown that an ideal hard limiter at the input to the demodulator adds no degradation to the bit error rate performance.