US 7035346

Patent Overview: US 7,035,346 B1

Title: Method and apparatus for desensitization of a wireless receiver

Patent number: US 7,035,346 B1 (application US09/100,569)

Original assignee: Lucent Technologies Inc. Current assignee listed as Google LLC (per the source's own caveat that listed assignees may be inaccurate).

Key dates: Priority/filing date 1998-06-19; publication/grant 2006-04-25; anticipated expiration 2018-06-19. Legal status listed as "Expired – Fee Related."

Inventors: Michael Eugene Burke; Joseph Thaddeus Lipowski; Leonard Edward O'Boyle; Rulon G. Van Dyke; Jack Chi-Chieh Wen.

Purpose: In wireless (CDMA) systems, base stations control mobile transmit power. In some situations it is advantageous to reduce a base station receiver's sensitivity—for example, to make the base station believe a mobile is farther away than it is, or to balance sensitivity between microcell and macrocell base stations during handoff, where conflicting power-control commands could otherwise arise. Prior art used an attenuator or lossy device before the low-noise amplifier; this always incurred insertion loss on the receive path (up to a few dB), potentially degrading overall noise figure.

Plain-language scope: Rather than attenuating the received signal, the invention sets receiver sensitivity by injecting a desensitization signal (such as a noise signal) onto the receive path, raising the noise power level relative to the signal power level and thereby reducing S/N and sensitivity. A desensitization source feeds a desensitization path with an adjustable attenuator setting the desired desensitization level; the path couples into the receiver's receive path. Injection may occur after the main amplifier, avoiding added noise-figure contribution and preserving full sensitivity when desensitization is not desired. Injection may be at RF, IF, or baseband stages, and the desensitization signal may be broadband noise, a continuous wave signal, a modulated signal, or a digital pseudo-random noise sequence.

Source: https://patents.google.com/patent/US7035346/en

What the excerpt does not establish: It does not provide the full claims, complete description, or drawings; claim scope, exact embodiment details, and FIG. 1–7b specifics are only partially described. It also does not establish litigation, validity, or ownership-transfer details, which are outside this overview's scope.