S-Band Synthesized Up-Converter

SSP’s S-Band Synthesized Up-Converter (Model SSP/SUC/02) is a Synthesized Up converter from fixed input center frequency of 70 MHz to synthesized output RF frequency in the range of 2.025 GHz to 2.125 GHz with the step resolution of 1KHz. The output level of the Up converted RF frequency can be varied with step resolution of 1 dB and the level can be varied through 30 dB.

The conversion gain of the up converter is typically 10 dB and the dynamic range is 50dB. The unit’s output RF frequency selection and the level variation can be done from the front panel keypad control of the unit.

The brief functional diagram of the unit is given as under. As shown, the input 70 MHz signal is received and subjected to double conversion for conversion to the output RF frequency in the range of 2.025 – 2.125 GHz range as required with step resolution of 1 KHz. The first conversion is done with a fixed LO at 700 MHz to yield a first IF of 770MHz. This IF is filtered and amplified and fed to the second conversion mixer IF port through a variable digital attenuator. The Mixer receives the LO frequency for conversion from a synthesized local oscillator which is in the range of 1255MHz to 1355 MHz and can be fed with the step resolution of 1 KHz The frequency of selection is done from the front panel which displays the output RF frequency selected while setting the corresponding LO frequency for conversion.

The output RF frequency from the second conversion is band pass filtered and amplified and fed to the output port at the rear panel of the unit. The unit has an internal FM modulator at the carrier frequency of 70MHz and the output unmodulated power level of -14dBm. This output is separately available on the rear panel and this output can be looped back to the input IF feed in port of the unit.