Patent ID: 8693576

Claim:
A method of transmitting symbols of a digital transmission constellation, the digital transmission constellation belonging to a set of digital transmission constellations ordered from a constellation with a smallest number of bits per symbol up to a constellation with a greatest number of bits per symbol, each digital transmission constellation having known respective error rate vs. signal-to-noise characteristics, the method comprising: identifying a number of bits m of a first digital transmission constellation from the set of digital transmission constellations that is configured to communicate up to a threshold error rate β (T) and having a greatest signal-to-noise ratio smaller than a signal-to-noise ratio of a received signal γ; identifying a number of bits {hacek over (m)} of a second digital transmission constellation from the set of digital transmission constellations that corresponds to a digital transmission constellation with a number of bits per symbol greater than the number of bits m of the first digital transmission constellation; determining a first probability of use 1−P of the first digital transmission constellation and a second probability of use P of the second digital transmission constellation that would generate an expected number of received erroneous bits corresponding to the threshold error rate β (T) , the second probability of use being complementary to the first probability of use and being determined as a function of the error rate of the first and second digital transmission constellations P e (m) (γ) P e ({hacek over (m)}) (γ) corresponding to the signal-to-noise ratio of the received signal γ and the number of bits m of the first digital transmission constellation and the number of bits {hacek over (m)} of the second digital transmission constellation; and transmitting a symbol with a digital transmission constellation selected randomly between the first and second digital constellations according to the first and second probabilities of use 1−P, P, respectively.