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:
Jan. 04, 2000
Filed:
Nov. 23, 1998
Applicant:
Inventors:
Fiona Maihri Wilson, Ware, GB;
Robin Paul Rickard, Bishop's Stortford, GB;
Assignee:
Northern Telecom Limited, Montreal, CA;
Primary Examiner:
Int. Cl.
CPC ...
H01Q / ; H01Q / ; H01Q / ;
U.S. Cl.
CPC ...
342372 ; 333 / ; 333 / ;
Abstract
Digital control of analogue beamformers utilising PIN diodes in a shunt circuit bi-phase attenuator arrangement is difficult because of the diodes extremely non-linear control response. There is disclosed a PIN diode circuit arrangement comprising a digital to analogue converter (DAC) with a reference voltage controller arranged to vary the DACs response to digital input signals to compensate for the PIN diode's non-linear response making this look substantially linear in the digital domain. The circuit preferably incorporates a feedback arrangement from the output of the DAC to its reference voltage input.