Patent ID: 8804868
Filing Date: 2014-08-12
Classification: H04L

Abstract:
1. A constant-amplitude and continuous-phase modulation method for modulating digital data and for demodulating said modulated digital data, said digital data being in the form of symbols having M number of states, where M is an integer greater than 2, the method comprising: recovering the symbols a(n) of the digital data to be transmitted, the symbols a(n) of the digital data being recovered periodically at a constant time interval T; associating, with each symbol a(n), a frequency pulse denoted h weighting the frequency pulse h where the function g is a continuous function of standard deviation σ and optimized weighting coefficients, where w e,m,i , and σ e,m,i , a e,m,i are the symbol and a number of successive derivatives of the function g to limit the spectral width of the digital data sent, a is an integral equal to 1, K is the degree of freedom associated with the weight w(i), and t is a given instant; applying a sum of successive weighted pulses to an input of a voltage-controlled oscillator to generate the modulated digital data to be sent; and filtering, on reception, the received modulated digital data by a single impulse response filter C wherein the parameters of the frequency pulses h