| 摘要 |
PURPOSE:To attain miniaturization and low power consumption by providing a delay circuit, a multiplier and a narrow band-pass filter in a transmission frequency converter so as to generate inherently a local oscillation frequency. CONSTITUTION:An input signal (x) is inputted to the 2nd mixer 16 together with an output signal (z) via a delay circuit 15. The output signal (z) is normalizedby an output amplifier 13 and an ALC circuit 14 so that an average value of the amplitude of an output (s) of the band-pass filter is ''1'', and an output of the narrow band-pass filter 17 is a difference between the signals (x) and (z). In applying frequency conversion to the input signal (x) through the use of a local oscillation signal (y) at a mixer 11, the system acts like the transmission frequency converter. |
