Abstract: An amplification device that amplifies a signal, the amplification device includes an amplification unit that amplifies the signal using supplied power, a variable power supply unit that changes the power supplied to the amplification unit in accordance with an envelope of the signal, a radiation unit that radiates light onto the amplification unit, and a control unit that controls the light to be emitted from the radiation unit in accordance with slope of the envelope of the signal.

Abstract: An amplification device that amplifies a signal, the amplification device includes an amplification unit that amplifies the signal using supplied power, a variable power supply unit that changes the power supplied to the amplification unit in accordance with an envelope of the signal, a radiation unit that radiates light onto the amplification unit, and a control unit that controls the light to be emitted from the radiation unit in accordance with slope of the envelope of the signal.

Abstract: In a digital radio transmission system for transmitting independent dual data by using cross polarization, an interference canceller detects cross polarization interference either directly or indirectly. An interference compensating signal is generated and applied to the main signal to cancel the interference element. In a case where no interference element is present, deterioration of cross polarization discrimination from an interference cancelling circuit is prevented by first determining whether an interference element actually exists and applying the interference compensating signal only when it does exist. The interference compensating signal can be attenuated based on the value of interference element so as to prevent undo deterioration of the cross polarization discrimination when the interference element is minimal.

Abstract: A cross polarization interference canceller cancels interference polarization by providing a phase difference detecting circuit for detecting a phase difference between a main polarization and an interference polarization component of the main polarization, and a phase shifter for shifting a data discrimination clock signal of the interference polarization wave component.

Abstract: A multi-value signal monitor circuit in a data transmitting and receiving system which transmits data after conversion into a multi-value signal and obtains the original data through analog-to-digital conversion of the received multi-value signal. The data is converted more accurately than the number of bits of data transmitted, during the analog-to-digital conversion on the receiving side. The position of the received signal relative to the quantization level is determined by utilizing the extra bits. When the extra bits indicate the multi-value signal is outside the specified range of the quantization level a pseudo error is detected. The pseudo errors are counted to produce a pseudo error rate which is used as an error rate for transmission path switching purposes.

Abstract: A radio receiver gradually changes the phase of a regenerated clock when an abnormal receiving condition is detected. Since clock phase changes gradually, an equalizer which reduces receiving distortion and a discriminator are periodically synchronized. As a result, if receiving distortion is reduced at this time, the operation of the equalizer and discriminator are normalized and the normal receiving condition can be recovered quickly.