As the input LNA was used industrial Vertex LXA-7550 (bought on e-bay). Technical spec.
Amplifier in need of modernization, which consists of gain reduction and replacement of a narrowband filter.
First, you must remove the original narrow-band filter. 
Instead, use a combination of two Mini-Circuit filters LFCN-8400 + HFCN-6010.
You must also add 14 dB pi-attenuator (consisting of 120-75-120 Ohm resistors):
.
The second part converter is made in a separate housing. Was designed circuitry:
Obtained a local oscillator following characteristics (pll width 350kHz, phase margin 60 deg, charge pump 2.5 ma):
Frequency: 6.305GHz
Phase noise:
100Hz -63dBc/Hz
1kHz -80dBc/Hz
10kHz -86dBc/Hz
100kHz -90dBc/Hz
1MHz -105dBc/Hz
Spoors +/- 13MHz <-83dBc
Screenshots phase noise measurements:
The final product may receive in the range of 7.25-8.45GHz and convert to 950-2150MHz.
Firmware, PCB full project and other see here >>>>>...........
-------------------------------- Added 9 Apr 2014 ---------------------------------