Noboru Kawada

Carrier phase control circuit

Modulator and demodulator apparatus

Backup apparatus against line defect and backup method against line defect

Initialization equalization for modulation and demodulation using special training pattern

Multiplex transmission system wherein analog signal is transformed to base band, random-transformed and superimposed on dispersed signal points in vector signal space

Simultaneous transmission of data and analog voice-band signals

Modulation and demodulation system

Modem for modulating and demodulating main signal and secondary signal with clock synchronized system and transforming secondary signal between start-stop system and clock-synchronized system

Frequency division multipplexed transmission of synchronous and start-stop data

Pll controller, method of pll control, and limiter