| 摘要 |
PROBLEM TO BE SOLVED: To obtain a spectrum analyzer for measuring TDMA wave having a wide frequency band and a robust gated sweep function by passing a trigger signal or a gate signal through a circuit for passing or delaying the signal by a specified time and the delivering the signal to a ramp voltage generator through a switch. SOLUTION: A down converter 30 comprises a mixer 31, a local oscillator 33 for trigger, and a BPF 32. An arbitrary burst wave taken out from the BPF 32 is fed to a trigger signal generation circuit 28 in order to generate a trigger at the edge of the burst wave. A variable delay circuit 36 can switch a path for passing a signal as it is and a path for delaying a signal by integer times of the burst width. A trigger signal or a gate signal p2 is fed to a ramp voltage generator 21 through a switch S1 for switching a continuous wave measurement and a TDMA (time division multiple path) wave measurement. This arrangement realizes a robust spectrum analyzer in which only 1 frequency can be selected among a wide band frequencies and can be processed at high sensitivity. |
