Variable-rate signalling in conjunction with coding for meteor burst communications

The author examines the use of variable-rate signaling in conjunction with error-correction coding for a meteor burst channel model which assumes that the received signal amplitude decays exponentially. The performance achievable with variable-rate signaling is quantified by calculating the cutoff rate. The average signal-to-noise ratio per bit required to support communications is calculated under the assumption that the code rate is equal to the cutoff rate. It is shown that the improvement of variable-rate signaling over fixed-rate signaling is large if the code rate is moderate to high, and that the improvement is small if the code rate is low and the decoder is provided with side information on the received signal level