Patent ID: 7746052
Filing Date: 2010-06-29
Classification: G01R

Abstract:
1. An apparatus for extending the operating frequency range of a spectrum analyzer comprising: first couplers having through paths connected in series from a RF signal source to a low frequency spectrum analyzer (LFSA), and each having a coupling path terminal; a frequency translation device having a first terminal for connecting to a local oscillator (LO), a second RF terminal, and having an output providing an IF signal for connecting to the LFSA; second couplers having through paths connected in series from a termination to the RF terminal of the frequency translation device, and having a coupling path terminal; filters each having an input connected to the coupling terminal of one of the first couplers, and having an output; and switches each having a primary terminal connected to the output of one of the filters and having a switching terminal for alternatively connecting to the coupling terminal of one of the second couplers and to a termination, the switches being controlled to connect the output of one of the first couplers through one of the second couplers to the RF input of the frequency translation device.