Patent ID: 7496151
Filing Date: 2009-02-24
Classification: H03F

Abstract:
1. A transmitting circuit, comprising; a signal modulation conversion circuit, which receives an inputted signal and performs a predetermined modulation or a predetermined signal conversion, and outputs a signal lower in resolution than said inputted signal; an amplifier of amplifying a signal outputted from said signal modulation conversion circuit; an isolation unit, one terminal of which is connected to the output of said amplifier; and a filter, which is connected to the other terminal of said isolation unit, and reduces an unnecessary frequency component of the signals outputted from said amplifier; wherein, in said isolation unit, magnitude of input reflection coefficient is smaller than magnitude of input reflection coefficient of said filter in a frequency band width from the frequency in which half the sampling frequency of said signal modulation conversion circuit is subtracted from the mean frequency of the signal outputted from said filter to the frequency in which half the sampling frequency of said signal modulation conversion circuit is added to the mean frequency of the signal outputted from said filter.