Highly efficient signal processing for frequency agile power line communications

A modified frequency hopping signaling scheme has received considerable attention by the designers of power line communication systems because of its insensitivity to frequency selective and time-variant attenuation and high level of interference. In a frequency hopping system, the increase of the data rate without an increase of the hop rate is possible only if the receiver can detect all information-bearing tones simultaneously. This paper presents the structure of the noncoherent optimum receiver that minimizes the number of required multiplications and memory locations. The receiver structure is based on the computation of equidistant DFT coefficients. The proposed demodulator can be used in systems with variable bit rate. With a slightly modified algorithm, rough synchronization can also be achieved. A comparison of the computational complexity confirms the superiority of the presented algorithm over direct DFT calculation and FFT algorithm