A multi-carrier group demodulator with chirp transform for personal/mobile system communication

A multicarrier transmission system using a bit-by-bit frequency hopping scheme with maximum likelihood error correction is proposed for high-quality personal/mobile communication systems. In the system, a group demodulator with a chirp transform for detecting high-speed hopping signals is adopted for a base station demodulator, resulting in hardware reduction by the use of a common single circuit. High-quality communication is performed by error correction for a bit-by-bit frequency hopping signal which is degraded by fading. Results using an experimental system have shown good performance. A bit error rate of 10 ^-4 is achieved with a signal-to-noise density ratio of 10 dB, which shows only 1.5-dB degradation from the case with Gaussian noise