The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 13, 2001
Filed:
Mar. 09, 1999
Kouji Miyauchi, Gyoda, JP;
Advantest Corp., Tokyo, JP;
Abstract
A spectrum analyzer that incorporates a YTO (YIG tuned oscillator) as a sweep frequency local oscillator and a YTF (YIG tuned filter) as a frequency pre-selector for an incoming signal and improves a C/N (carrier to noise) ratio with low cost. The spectrum analyzer includes a YTO first local oscillator which is swept in response to a ramp signal, a base band block having a first frequency mixer for producing a first intermediate frequency (IF) signal and a second frequency mixer for producing a second IF signal, a high band block having a YTF frequency preselector for selecting frequency components in the input signal in response to the ramp signal and a high band frequency mixer for producing the second IF signal by mixing the input signal through the YTF with the first local signal, and a local signal mode switch for either directly providing the first local signal to the high band frequency mixer or through a frequency divider which divides the frequency of the first local signal by a predetermined division ratio. The YTO has a sweep frequency range which is 1/2 of a sweep frequency range of the YTF, and the division ratio of the frequency divider is two (2).