Tunable trigger acquisition system and method for making in-service time-domain signal measurements
US5493209A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 1993 |
| Grant date | Feb 20, 1996 |
| Priority date | — |
| Expiry date | Oct 20, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R23/16
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A spectrum analyzer (50) has a tunable trigger acquisition system (52) that includes a selectable trigger acquisition bandwidth. Sufficiently wide signal acquisition bandwidth is obtained by tapping into a high-frequency IF amplifier (54) signal and down-converting it to a moderate IF frequency for trigger extraction. A down-conversion local oscillator (62) is phase-lock-loop (64) tunable over a range of the high IF frequencies to allow extracting a time and frequency selectable trigger from the desired carrier signal frequency even if the spectrum analyzer is substantially offset in frequency from the desired carrier. The moderate frequency IF amplifier (66) includes a switchable bandpass filter (68) that provides adequate selectivity to detect triggers from a variety of signal types while rejecting unwanted signals such as adjacent channel CATV carriers that are often detectable when the measurement frequency is offset toward the channel edges.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.