Patent ID: 7159236
Filing Date: 2007-01-02
Classification: H04B,H04N

Abstract:
1. A transmission/reception integrated radio-frequency apparatus comprising, an input/output terminal for inputting/outputting of a radio-frequency signal; a reception system block for processing a reception radio-frequency signal supplied to the input/output terminal; a transmission processing section including a semiconductor element for outputting a transmission radio-frequency signal to the input/output terminal; a first high-pass filter connected between the reception system block and the input/output terminal and having a first cut-off frequency (lower-limit frequency) less than a lower-limit frequency of reception frequencies; a second high-pass filter connected to an output terminal of the transmission processing section and having a second cut-off frequency (lower-limit frequency) in a frequency band lower than said first cut-off frequency; a low-pass filter connected between the second high-pass filter and the input/output terminal and having a cut-off frequency (upper-limit frequency) in a frequency band which is higher than said second cut-off frequency and tower than said first cut-off frequency; and an overvoltage breakdown protection circuit connected between the output terminal of the transmission processing section and the second high-pass filter.