Development of a Wide-Band Intermediate Frequency Receiver to Minimize the Second Harmonic Signal

In this study, an eight-channel wide-band intermediate frequency (IF) receiver with S-band input frequency, output of 200 MHz, and a signal bandwidth 160 MHz was developed. The performance measurement results the IF showed that fundamental second harmonic were involved in output. This caused by nonlinearity characteristics final stage amplifier. Therefore, amplifier changed to differential amplifier, circuit modified reduce signal. After improvement, gain 33 dB, Output 1 dB Gain Compression Point(OP1dB) > 15.8 dBm, 3rd Intercept Point(OIP3) 25.7 dBm suppressions range −83.30 dBc −75.19 when power −10 dBm. result satisfied requirement system for suppression lower than −70 dBc.