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:
Apr. 13, 1993
Filed:
Jan. 31, 1991
Kenichiro Kawasaki, Saitama, JP;
Pioneer Electronic Corporation, Tokyo, JP;
Abstract
A satellite transmission capturing method for the GPS receiver whereby PLL operation is stopped until the demodulation intensity of a demodulator reaches a predetermined level. The frequency of the reproduced carrier of the demodulator is consecutively changed in increments of a frequency range wider than the PLL capture range in search for satellite transmissions. This allows the demodulation intensity to reach the predetermined level in fewer frequency changing steps than ever before. Thus the time required to capture the desired satellite transmission is reduced. Where the integral time constant of a low pass filter in the demodulator is set to a value smaller than that in effect during PLL operation until the demodulation intensity of the demodulator reaches the predetermined level, a wide band demodulation intensity curve is used in search for satellite transmissions until that level is exceeded. This further widens the frequency range in which to search satellite transmissions, and the time required to capture the desired satellite transmission is further shortened accordingly.