Pioneer Electronic Corporation

Pioneer Ansafone Manufacturing Corporation

Junichi Shibata

Katsuaki Kawamura

Masashi Shimakata

Shintaro Gomi

Yasuhiro Oshime

Shigeki Takeda

Hitoshi Ando

Shozaburo Sakaguchi

Masaya Adachi

Hayato Yoshida

Hiroshi Kojima

A satellite signal tracking system for a GPS receiver, wherein a GPS satellite is recaptured within a very short period of time, after the interruption of reception is cleared as by passing through a tunnel and the like, by widening a band width of the PLL search frequency gradually every after repeating the search for the satellite signal, performing a narrow-band search repeatedly as varying its center frequency along the Doppler shift curve, performing a narrow-band search for a specific period of time which is given by dividing the capture range of the PLL circuit by the Doppler shift rate and a wide-band search with use of an estimated satellite signal receiving frequency which is given by recalculating the Doppler frequency of the GPS satellite at the very moment according to the almanac data of the GPS satellite and is assigned as the center frequency, and, still further, performing the search for GPS satellites repeatedly with the estimated satellite signal receiving frequency in the center for recovering the function to perform the positional reckoning which is the primary function of the GPS receiver.

GPS satellite signal tracking system for GPS receivers

A microwave bandpass filter having a wide bandwidth, low loss, and yet which requires only a relatively small circuit area. A generally annularly shaped unit-wavelength resonator is formed on a dielectric substrate, disposed between input and output matching circuits. The unit-wavelength resonator is formed by a pair of semi-annular strips disposed opposite one another and having opposing stubs defining therebetween a gap of predetermined width.

Microwave filter

A complex antenna system including at least two loop antennas crossing each other and connected with each other at the electric neutral points thereof, and a rod antenna positioned at the central portion of the loop antennas. An FM and/or AM tuners combined with the complex antenna system utilizes selected one of the loop antennas for receiving an FM wave so as to avoid multi-path noises.

Complex antenna system and FM/AM receiver

An antenna array system which comprises at least one balanced antenna having an electric neutral point and two output end terminals positioned closely to each other, at least one unbalanced antenna having one end thereof dc-coupled with the electric neutral point of the balance antenna and the other end thereof positioned closely to the end terminals of the balanced antenna, first means for picking up a first frequency wave signal such as FM wave signal from the balanced antenna, and second means for picking up a second frequency wave signal such as an AM wave signal from the unbalanced antenna.

Antenna array system usable for AM/FM receiver

An FM receiver provided with an array of antennas and suitable for use in a moving vehicle such as a motorcar, which is provided with means for automatically avoiding multipath noises. The means so operates as to connect one of the antennas in an instantaneously best sensing condition to an FM tuner.

Growing community of inventors

Tokorozawa, Japan

Junichi Shibata