Patent ID: 7295635

Claim:
A method for processing a first and a second signal, the first signal being spread over a wide band channel and the second signal being spread over a narrowband channel, and modulating one and the same carrier in a single carrier phase tracking loop controlled by a carrier phase discriminator, comprising the steps of: generating two components sine and cosine phase shifted of a local carrier at the frequency of the carrier, demodulating the first and second signals with the sine and cosine phase shifted components of the local carrier so as to obtain a first couple of quadrature demodulated components I WB , Q WB for the first wide spread signal and a second couple of quadrature demodulated components I NB , Q NB for the second narrow spread signal, in a single code tracking loop controlled by a code discriminator, generating a code clock signal, on the base of the code clock signal, generating, a first punctual code and a first Δ code, and a second punctual code and a second Δ code compatible with the pseudorandom code, correlating the first couple of quadrature demodulated components I WB , Q WB with the first local punctual and Δ codes in order to obtain four demoduladed and dc-spread signal components I PWB , I ΔWB , Q PWB and Q ΔWB issued from the wide channel, correlating the second couple of quadrature demodulated components I NB , Q NB with the second local punctual and Δ codes in order to obtain four demodulated and de-spread signal components I PNB , I ΔNB , Q PNB and Q ΔNB issued from the narrow channel, generating an input signal for the phase discriminator mixing the demodulated and de-spread signal components I PWB , Q PWB , I PNB , Q PNB issued from the correlations of the wide (WB) and narrow (NB) channel signals with the punctual codes, and generating an input signal for the code discriminator, mixing the demodulated and de-spread signal components I PWB , I ΔWB , Q PWB , Q ΔWB , I PNB , Q ΔNB issued from the correlations of the wide (WB) and narrow channel (NB) signals with the Δ codes; and wherein, the input signal for the phase discriminator has its quadrature components I p opt Q p opt defined by mixing the signal components I PWB , Q PWB , I PNB Q PNB issued from the correlations of the wide and narrow channel signals with the punctual codes according the formula: I p opt =αI pWB +βI p NB Q p opt =αQ pWB +βQ p NB α, β being weighting parameter.