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. 16, 1993
Filed:
Nov. 09, 1990
Brian F Hearn, Tallahassee, FL (US);
Global Communications, Inc., Tallahassee, FL (US);
Abstract
An inexpensive portable RF (radio frequency) microcontroller-based digital spectrum analyzer is automatically calibrated for passband amplitude tilt/variations. Resulting software-obtained calibration parameters are used during operation to reduce or eliminate passband amplitude errors. The spectrum analyzer also includes a PLL frequency synthesizer arrangement, but the PLL controls a VCO only during calibration to derive calibration values for controlling a digital-to-analog converter. During normal operation, the VCO is driven in an open loop configuration under software control using such calibration values--achieving nearly the accuracy of closed loop operation while avoiding the penalty of long PLL lock time. These amplitude and frequency calibration techniques and arrangements permit the spectrum analyzer to have relatively inexpensive components and circuit arrangements and nevertheless achieve high accuracy over a wide band.