Continuous phase modulation

About: Continuous phase modulation is a research topic. Over the lifetime, 3199 publications have been published within this topic receiving 37245 citations. The topic is also known as: CPM.

Soft-output detection of CPM signals in frequency flat, Rayleigh fading channels

Abstract: Symbol-by-symbol detection algorithms are useful in systems in which soft-decision metrics are important, e.g., systems with interleaved coded modulation. A soft-output algorithm for the detection of continuous phase modulated (CPM) signals transmitted over frequency flat, Rayleigh fading channels is developed. Since the optimum detector is computationally too complex for any practical implementation, some suboptimal detectors which give near optimal performance are proposed. Some theoretical approximations for the performance of the interleaved coded system are given. The performance of the soft-output algorithms is also extensively characterized by means of Monte-Carlo simulations.

Data aided symbol timing system for precoded continuous phase modulated signals

Abstract: Data aided carrier phase and symbol timing synchronizers are implemented at baseband as digital modulators isolating input signal inphase and quadrature component signals fed into inphase and quadrature Laurent transforms that function as data detector to provide odd and even data bit multiplexed output data signal while cross coupling the inphase and quadrature transformed outputs for removing data modulation in error signals to correct phase errors and timing errors in the received signal so as to provide reliable data demodulation of noisy received signals having dynamic carrier phase and symbol timing errors as found in continuous phase modulation communications systems such as Gaussian minimum shift keying communications systems.

System implications in designing a 60 GHz WLAN RF front end

Abstract: In this paper, we seek to evaluate the performance of a 60 GHz WLAN system taking into account RF circuitry imperfections and hardware requirements for various modulation techniques. A model of an RF frontend is developed, including physical imperfections of the circuitry such as power amplifier (PA) nonlinearity and voltage controlled oscillator VCO phase noise. Given the RF front-end model, several modulation techniques such as Orthogonal Frequency Division Multiplexing (OFDM) and Continuous Phase Modulation (CPM) are considered. The evaluation of the system performance in terms of bit error rate allows a better understanding of physical circuitry limitations, and optimal modulation parameters as well as circuit design recommendations can be derived.

Minimum entropy approach for carrier frequency recovery

Abstract: This paper introduces a new carrier frequency recovery approach. It can be applied before modulation classification and/or demodulation of the M-ary PSK signals. It relies on the entropy of the instantaneous phase probability density function, and uses the fact that it reaches minimum when the receiver is fine-tuned to the unknown carrier frequency. This estimator is applicable to algorithms requiring high accuracy without any a priori knowledge concerning modulation scheme, signal contents (bit-stream), or its timing parameters. Simulation results have proved the robustness of the algorithm: for low carrier to noise ratios (CNR), corresponding variances are proportional and close to Cramer-Rao lower bounds (CRLB). For CNR greater than 20 dB, they are constant and limited by the resolution of the algorithm.