A method of communication between a first node and a second node for a system where a plurality of different channels is provided between said first and second node. The method comprises the step of calculating an integrity output. The integrity output is calculated from a plurality of values, some of said values being the same for said different channels. At least one of said values is arranged to comprise information relating to the identity of said channel, each channel having a different identity. After the integrity output has been calculated, Information relating to the integrity output is transmitted from one of said nodes to the other.

Integrity check in a communication system

Noise discrimination in signals from a plurality of sensors is conducted by enhancing the phase difference in the signals such that off-axis pick-up is suppressed while on-axis pick-up is enhanced. Alternatively, attenuation/expansion are applied to the signals in a phase difference dependent manner, consistent with suppression of off-axis pick-up and on-axis enhancement. Nulls between sensitivity lobes are widened, effectively narrowing the sensitivity lobes and improving directionality and noise discrimination.

Beam former using phase difference enhancement

Method and apparatus for improving noise discrimination in multiple sensor pairs

A position detection method, system, and computer readable article of manufacture tangibly embodying computer readable instructions for executing the method for detecting the position of a sound source using at least two microphones. The method includes the steps of: emitting a reproduced sound from the sound source; observing the reproduced sound and an observed sound at the microphones; converting the reproduced sound and the observed sound into electrical signals; transforming the signals of the reproduced sound and of the observed sound into frequency spectra by a frequency spectrum transformer apparatus; calculating Crosspower Spectrum Phase (CSP) coefficients of the frequency spectra of the signals by a CSP coefficient calculator apparatus; and calculating distances between the position of the sound source and the positions of the microphones based on the calculated CSP coefficients by a distance calculating apparatus, thereby detecting the position of the sound source.

Method and system for position detection of a sound source

The invention discloses a passive sound source two-dimensional DOA (direction of arrival) estimation method under a complex environment, comprising the steps that (1) voice signals in a room are collected by a uniform circular array; (2) the voice signals received by the uniform microphone array are preprocessed in a spectral subtraction method; (3) an M_AEDA algorithm is adopted to estimate the relative time delay of each microphone; (4) a direction coefficient vector is determined according to a direction coefficient formula; (5) the direction coefficient vector and the voice signals preprocessed in the step (2) are correspondingly multiplied to serve as an input signal for minimum variance undistorted response; (6) an minimum variance undistorted response algorithm is adopted to process the input signal; and (7) the output average power is subjected to spectrum peak search, and the estimation value of the sound source two-dimensional DOA is obtained accordingly. The passive sound source two-dimensional DOA (direction of arrival) estimation method under the complex environment has the advantages that the sound source can be accurately located under a reverberation and low signal-to-noise ratio environment; during sound source location, the location accuracy and accuracy rate are high; and the required equipment is simple, the passive sound source two-dimensional DOA estimation method can be applicable to real life in the aspects of video conference, robots and the like.

Passive sound source two-dimensional DOA (direction of arrival) estimation method under complex environment

PURPOSE: To provide an attachable/detachable storage device and a radio communication terminal which flexibly and easily copes with new ciphering or the like by the attachable/detachable storage device where ciphering algorithms are stored. CONSTITUTION: An attachable/detachable storage part 115 where plural ciphering algorithms, identifiers corresponding to these ciphering algorithms in 1:1, and a ciphering table showing the correspondence relations between these identifiers and ciphering algorithms are stored is set to a setting part 116 where it can be set without opening the main body cover. An ciphering algorithm is selected by a cipher selection part 110, and voice data is ciphered in a ciphering part 104 based on the arbitrary selected ciphering algorithm to output a cipher text. A cipher data block generation part 105 refers to the ciphering table to read out the identifier corresponding to the selected ciphering algorithm and adds it to the cipher to output a cipher data block.

Radio communication terminal, radio base station, and communication system provided with them

PROBLEM TO BE SOLVED: To easily search the direction of a sound source existing on a plane as a specified state SOLUTION: When the directions of the sound sources S of the microphone arrays MA1 and MA2 can be searched under the condition that a distance between microphone arrays MA1 and MA2 is known, the positions of the sources S can be easily searched from these pieces of the information COPYRIGHT: (C)2003,JPO

Method for searching direction of sound source/ electromagnetic wave source, method for searching position of sound source/electromagnetic wave source and method for recognizing specific sound source/ electromagnetic wave source

PURPOSE: To prevent the interference of a control radio wave between base stations automatically with respect to base stations in a private digital radio communication system wired-connected to an electric communication line installation. CONSTITUTION: Base stations BS1-3 monitor an available control frequency and a radio wave state of a slot in advance when the control radio wave is sent to mobile stations PS1-3. In the monitor of the base stations BS, a request of monitor command publication is made to a control radio wave state monitor command section 2 when a power supply ON detection section 4 detects power ON and an incoming call disable state detection section A1 detects the unarrival of an incoming call or at each prescribed time set by a routine timer A2 or by their combinations to start a radio wave state monitor section 1. Then the radio wave state monitor section 1 selects a radio wave not in use among monitor radio waves and starts transmission and uses the set control radio wave till a succeeding radio wave state is monitored. COPYRIGHT: (C)1996,JPO

芳徳黒木

Papers

Radio communication terminal, radio base station, and communication system provided with them

Method for searching direction of sound source/ electromagnetic wave source, method for searching position of sound source/electromagnetic wave source and method for recognizing specific sound source/ electromagnetic wave source

Radio control signal transmission system, base station and mobile station

芳徳 黒木

Papers

Radio communication terminal, radio base station, and communication system provided with them

Method for searching direction of sound source/ electromagnetic wave source, method for searching position of sound source/electromagnetic wave source and method for recognizing specific sound source/ electromagnetic wave source

Radio control signal transmission system, base station and mobile station

芳徳黒木