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:
May. 11, 1999
Filed:
Nov. 24, 1997
Yasuhiro Kobayashi, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A pager includes a radio frequency (RF) attenuator which is initially rendered inoperative and which initiates attenuation of an incoming RF signal in response to a control signal. An amplifier is coupled to amplify the output of the attenuator. A signal level monitor (24, 26), coupled to the amplifier, determines if the output of the amplifier exceeds a predetermined level. A demodulator (16) is coupled to reproduce a base band signal from the output of the amplifier. A controller, following the demodulator, attempts to establish bit sync during each of a plurality of conventional and intermittently executed preamble searches. If bit sync is not established in a given preamble search and if the level monitor indicates that the output of the amplifier exceeds the predetermined level, the controller applies the control signal to the attenuator for activating the attenuator. Further, the controller extends the given preamble search by a predetermined time period for further determining whether or not bit sync is established. The attenuator, once being energized, continues to attenuate incoming RF signals until a predetermined time period elapses and another high input signal is received without establishing bit sync.