Uniden Corporation

Akio Horibe

Shigeo Sato

Toshiaki Fujikura

Masaki Matsui

Muneki Ito

Hitoshi Hachiga

Takayuki Iguchi

It is an object of the present invention to provide an indoor mobile communication device having a simple structure, providing a sufficient communication range, and also providing for stable communication with a small fading effect. In order to attain this object, the present invention provides an indoor mobile communication device which is equipped with an antenna with fixed direction characteristics such as electromagnetic wave emission direction and half-power angle and is capable of mobile communications, while freely changing the position and direction inside an indoor space, this device comprising an antenna for transmission and reception of linearly polarized waves, the antenna having a half-power angle within 180 degrees and a directivity such that the emission level within a range of from 90 degrees to 270 degrees, as measured from the maximum emission direction, is less than the maximum emission level by 10 dB or more and a wireless unit for conducting modulation and demodulation of the signals superimposed on the electromagnetic waves transmitted and received via the antenna.

Indoor mobile communication device

The object of the present invention is to propose a re-radiating antenna system that efficiently radiates radio waves emitted from the antenna of a portable wireless device and efficiently receives incoming radio waves. To realize this object the re-radiating antenna system according to the present invention comprises coupling means for receiving radio waves radiated from the antenna of a portable wireless device, re-radiating means for re-radiating radio waves received by the coupling means and transmission means for transmitting radio waves received by the coupling means to the re-radiating means. The antenna of the portable wireless device and the coupling means are each formed of patch antennas, and these patch antennas are disposed to oppose each other.

Re-radiating antenna system

It is an object of the present invention to improve the diversity gain by conducting linear prediction of fading fluctuations and switching antennas. In order to attain this object, the diversity receiver in accordance with the present invention comprises a plurality of antennas for receiving wireless signals subjected to direct spread modulation, an antenna switch for conducting antenna connection switching thereof, a primary demodulator for demodulating the wireless signals and obtaining a spread spectrum signal, a matched filter for finding a correlation value of the spread spectrum signal and a spread code for demodulation, a mean value computation unit for finding a mean SNR of the received signal by converting the maximum correlation value to a value per 1 frame, an estimation unit for linear prediction of the SNR of the received signal based on the time series data of the mean SNR, and a level comparator for comparing the SNR of the received signal that was predicted by the estimation unit with a threshold value and outputting a control signal for conducting antenna switching to the antenna switch.

Diversity receiver

The present invention provides a diversity receiving device with superior interference resistance in a simple construction, comprising a plurality of antennas (); an antenna switching device () that selects any one of a plurality of antennas () and carries out connection switching thereof; a demodulator () that demodulates a wireless signal and obtains a baseband spread spectrum signal; an A/D converter () that A/D converts the baseband spread spectrum signal and generates chip data; a digital matched filter () that finds the correlation value of the chip data and the spreading code; a maximum correlation value detection portion () that detects the maximum correlation value; an average value calculation portion () that finds the average value per frame of the maximum correlation value; and a level comparison device () that compares the above-mentioned average value and a predetermined threshold value, and outputs a control signal to the antenna switching device () to control antenna switching in the antenna switching device ().

Diversity receiving device

An optimum antenna is readily selected from three or more antennas, by means of an existing device which is only capable of switching between two antennas. The device of the invention comprises: a switching device for receiving signals from two antennas as a pair of antenna selected from three or more antennas, and outputting the first signal (DATADET) indicating that receiving is in progress, and the second signal (ANTSEL) indicating which antenna being used for receiving; a judgement circuit for judging which antenna is suitable for receiving and actually being used in the said pair of antenna, on the basis of the said first and the said second signal of the said switching device; a setting circuit for resetting said pair of antenna on the basis of the output of said judgement circuit; and a switching circuit for selecting two antennas which is set by the said setting circuit as a pair and supplying the output thereof to the said switching device.

Diversity antenna switching device and method, and storage medium

The present invention provides an antenna for a radio device that has sufficient mounting strength with little deterioration in antenna property. A first antenna and a second antenna are provided substantially parallel to each other at both ends of a circuit board Feeding points are provided at one end of first antenna and second antenna , and are fed in equiphase. As radio-frequency currents are in equiphase, vertically polarization are radiated, but horizontal radio-frequency currents are in antiphase, so horizontally polarization are not radiated. Furthermore, antennas may be formed by the mounting portions of the circuit board on the housing.

Growing community of inventors

Tokyo, Japan

Akio Horibe