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:
Mar. 12, 2002
Filed:
Apr. 28, 1998
Nuri Ruhi Dagedeviren, Red Bank, NJ (US);
Lynn Emery Ditty, Northampton, PA (US);
Donald Lars Duttweiler, Rumson, NJ (US);
Gerard Joseph Pepenella, Blandon, PA (US);
Dewayne Alan Spires, Plaistow, NH (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
Quantization noise, introduced into data transmission when analog signals are translated into PCM code using the logarithmic conversion of &mgr;-law or A-law rules necessary to accommodate the transmission of voice signals, limits the maximum attainable speed of data transmission. However, when the PCM code signals represent data (rather than voice signals), linear conversion of analog data signals into the PCM code would avoid such logarithmic quantization noise. To signal the translating codec that a digital modem call is being made, the digital modem allocates one or more of the least significant bit positions of the code representing the 2100 Hz answer-tone-with-phase-reversal (specified in ITU-T Recommendation G. 165) to send a repetitive pattern “P ” to signal to the associated codec that a digital modem connection has been made. When the codec detects the P pattern it will linearly convert analog data signals into PCM code, thereby reducing the introduction of logarithmic quantization noise.