Patent ID: 6980593
Filing Date: 2005-12-27
Classification: H04B

Abstract:
1. A wireless transmission reception including a transmitter and a receiver, the transmitter including a compressor for compressing a transmit signal and a pre-emphasis circuit for emphasizing an output signal of the compressor at high frequencies, the receiver including demodulation means, a first de-emphasis circuit, a expander circuit and a second de-emphasis circuit, the expander circuit having a variable gain amplifier, the expander circuit connected to an output of the demodulation means, the first de-emphasis circuit connected to the output of the demodulation means and de-emphasizing the output signal of the demodulation means in high frequencies, the second de-emphasis circuit connected to an output of the expander circuit and de-emphasizing the output signal of the expander at high frequencies, the wireless-transmission reception system comprising: the pre-emphasis circuit in the transmitter emphasizing an output signal of the compressor in +6 dB in both the gain and the high frequencies; the first de-emphasis circuit disposed in the receiver and connected to the output of the demodulator in parallel with the expander circuit, an output of the first de-emphasis circuit connected to the rectifier circuit, the first de-emphasis circuit de-emphasizing the output signal of the demodulation means in −6 dB in both the gain and the high frequencies; and the second de-emphasis circuit de-emphasizing the output signal of the expander circuit in −6 dB in both the gain and the high frequencies; the output signal of the first de-emphasis circuit controlling a gain of the variable gain amplifier.