Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Mitsuru Takeuchi

Jun Ido

Eiji Arita

Satoshi Suzuki

Hiroyuki Nagahama

Masakazu Morita

Hidenori Akita

Kaoru Nakamura

Yukihiro Kadota

Tadashi Sakaguchi

Kazuhisa Masimo

Miho Murano

Norihiko Iio

A receiveris comprised of a first frequency changing circuitfor converting a received signal including two or more broadcast waves into a first intermediate frequency signal with a local oscillation, a band separation filterconsisting of a multistage FIR type filter for allowing bands included in the two or more broadcast waves converted into the above-mentioned first intermediate frequency signal to pass therethrough simultaneously, and a second frequency changing circuitfor converting the received signal which is outputted by the above-mentioned band separation filterand which is limited to the above-mentioned two or more broadcast waves which the receiver desires to receive into a second intermediate frequency signal from which each of the broadcast waves can be sampled at a frequency at which the broadcast waves do not interfere with one another.

Receiver

A receiveris comprised of a first frequency changing circuitfor converting a received signal including two or more broadcast waves into a first intermediate frequency signal with a local oscillation, a band separation filterfor allowing bands included in the two or more broadcast waves converted into the first intermediate frequency signal to pass therethrough simultaneously, and a second frequency changing circuitfor converting the received signal which is outputted by the band separation filterand which is limited to the two or more broadcast waves into a second intermediate frequency signal from which each of the broadcast waves can be sampled at a frequency at which the broadcast waves do not interfere with one another.

A diversity receiver includes: a plurality of demodulating means for demodulating inputted OFDM signals, to output their demodulated signals; noise component calculating means provided for each demodulating means, for calculating noise components included in the demodulated signals outputted from corresponding demodulating means; channel profile calculating means provided for each demodulating means, for calculating channel profiles based upon the demodulated signals outputted from corresponding demodulating means; transmission channel decision means for determining transmission channel based upon the channel profiles; reliability information generating means for generating reliability information indicating reliability of the demodulated signals outputted from each demodulating means, based upon the noise components and the results of the determinations by the transmission channel decision means; a weighting factor calculating means for calculating, depending on the reliability information, weighting factors used in combining the demodulated signals outputted from each demodulating means; and a combining means for combining, depending on the weighting factors, the demodulated signals outputted from each demodulating means.

Demodulator, diversity receiver, and demodulation method

A digital broadcasting receiving apparatus is characterized in that the digital broadcasting receiving apparatus is provided with an antenna combination determination processing unit for selecting at least two antennas from among a plurality of antennas which have directivities in different directions and each of which receives a digital broadcasting wave transmitted from outside the digital broadcasting receiving apparatus, and for providing an instruction for switching among the above-mentioned plurality of antennas on the basis of a state of reception of the digital broadcasting waves received by the selected antennas, and switches for switching among the above-mentioned plurality of antennas according to the instruction from the above-mentioned combination determination processing unit.

Digital broadcasting receiving apparatus

A digital broadcasting receiving apparatus has a signal level detecting circuit; a peak detecting section; an abnormal peak deciding section; a specified peak deciding section; a prescribed in-band power deciding section; and makes a decision as to whether a signal being received is a digital broadcasting signal or not according to decision results output form the signal level detecting circuit, the abnormal peak deciding section, the specified peak deciding section and the prescribed in-band power deciding section.

In an OFDM receiver with a diversity configuration having a plurality of demodulation modules, to perform FFT window position recovery and clock recovery, the gain values calculated by the AGC units () provided in the demodulation modules for adjusting the level of the received signal are supplied to a correlation combiner (); the correlation combiner () multiplies the correlation signals supplied from the correlation detectors () in the demodulation modules by coefficients calculated from the gain values, then adds the products to generate a combined correlation signal and supplies it to an FFT window position recovery unit () and a clock error detector (). FFT window position recovery and clock recovery can thus be performed properly without depending on any one demodulation module.

Demodulator, receiver, and demodulation method

A delay profile generating circuitgenerates a delay profile signal. Concerning the delay profile signal, a ghost decision circuitmakes a decision as to the presence or absence of ghosts that will appear during traveling of a mobile vehicle in response to a transmission mode signal fed from a changeover switch. The delay profile signal and the decision signal about the presence/absence of the ghosts are delivered to a window control circuitvia an accumulator. The window control circuitsets and controls the FFT window position of an FFT circuitin response to a guard correlation signal fed from a guard correlation signal generating circuitand a signal fed from the accumulator

Digital broadcasting receiving apparatus with channel estimation function

A plurality of orderers with their own code systems procures materials from companies (supply companies) with which the orderers have business relations. In this material procurement system, a name register master is provided for making correspondence between goods name codes provided by each of the supply companies and material codes of the orderers. When necessary materials are procured from the supply company, the orderer goods name codes are used for specifying the materials. Further, an order processor is provided. The order processor refers to the name register master, and combines orders of the materials with a same orderer goods name, if the same goods name of the supply company is in the name register master. The order processor also divides the orders and orders to another company by referring to the name register master, if the materials in a quantity beyond a predetermined number must be ordered.

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Tokyo, Japan

Mitsuru Takeuchi