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In the last few years digital video broadcast services supported by geostationary satellites (DVB-S) have grown rapidly. In a DVB-S receiver the low noise block down-converter (LNB) translates the RF satellite signals picked up by a parabolic dish from the Ku-band (10.7-12.75GHz) to an intermediate frequency IF ranging in the L-band (0.95-2.15GHz). The converted IF band is then sent to a decoder for tuning and digital demodulation. LNB specifications [1,2] are very challenging. Indeed, an LO phase noise as low as -95dBc/Hz at 100kHz frequency offset from the carrier at 10GHz has to be guaranteed. In addition, an amplitude gain variation and an output P 1dB respectively within 8dB and +5dBm over the 2.05GHz RF band must also be met. Up until now, commercial LNBs have all been fabricated using discrete components. Usually, GaAs high electron mobility transistors (HEMT) and FET devices are used for the down-converter block, while dielectric resonator oscillators (DRO) are employed to generate the LO signal. An integrated approach to LNB implementation would drastically reduce manufacturing costs. Moreover, the use of a PLL to generate the LO signal would eliminate the need for a testing phase to guarantee the accuracy of the oscillation frequency.

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