Casio Computer Co., Ltd.

Sanyo Electric Co., Ltd.

Kunio Okada

Shimpei Matsuda

Hiroya Ito

Yoshihito Kitayama

CPU instructs RF controlling section to switch RF section from an inoperative mode to an operation mode and from the operation mode to the inoperative mode. When all of five pieces of sub-frame data have not been acquired, RF section is switched intermittently from the inoperative mode to the operation mode in synchronization with transmission of lacking sub-frame data, thereby acquiring such lacking sub-frame data. When all the five pieces of sub-frame data have been acquired, the current position is calculated using positional information contained in the sub-frame data. A part of five pieces of sub-frame data including the first to fifth sub-frame data transmitted from a satellite in a time series manner is acquired from GPS signal received in the operation mode, and the remaining part of the five pieces of sub-frame data is acquired in operation mode set at other timing, and then the positional information is judged based on the five pieces of sub-frame data acquired in the above manner.

Position detecting apparatus and method of detecting a position

When an OFDM demodulator circuit performs the waveform equivalence of carrier signals outputted from an FFT processing circuit, the OFDM demodulator circuit extracts correction coefficients corresponding to the gain of a reception signal outputted from a tuner unit from a correction coefficient table, and phase corrections are performed in a phase correction circuit based on the extracted correction coefficients. After that, the OFDM demodulator circuit performs the waveform equivalence processing with a transmission path equivalent circuit. Thereby, even if a C/N value is deteriorated owing to the amplification of an OFDM signal, the influence on the receiving performance of a receiving apparatus can be curbed, and a receiving performance can be improved.

OFDM signal demodulator circuit and OFDM signal demodulating method

A receiver has an amplifier for amplifying a TV broadcast signal. A mixer mixes the amplified signal with an oscillation signal corresponding to a channel selection signal and generates a low frequency signal. A bandpass filter generates a signal having an amplitude corresponding to the low frequency signal. Electric field intensity filtering circuits filter the low frequency signal. A subtractor calculates a difference between the output from the filtering circuits and the output from the bandpass filter to generate a difference signal which is negatively fed back signal to the amplifier when an amplitude of the difference signal is larger than a predetermined value. The signal from the filtering circuit is the negative feed back signal when the amplitude of the difference signal is not larger than the predetermined value. An AGC signal corresponding to an electric field intensity of the output from the mixer is inputted to the amplifier.

Broadcasting receiver and method of receiving a broadcasting wave

An Orthogonal Frequency Division Multiplexing (OFDM) demodulator, an integrated circuit for OFDM demodulation and an OFDM demodulation method in which at least one of a predictive value generated by a low order symbol filter and a predictive value generated by a high order symbol filter interpolates the order of a high symbol direction, or a weighted composite value of the predictive values, is selected to accomplish waveform equivalence of a carrier outputted from a transform section.

Orthogonal frequency division multiplexing (OFDM) demodulator, integrated circuit for OFDM demodulation and OFDM demodulation method

The invention arranges an auxiliary antenna in the neighborhood of an antenna, and a voltage applied to the auxiliary antenna is changed based on the reception quality of a received signal received by the antenna. Thereby, the reception characteristic of the antenna is changed. Moreover, the optimum antenna is selected among a plurality of arranged antennas based on the reception quality of the received signals received by the plurality of arranged antennas.

Receiving apparatus and receiving circuit

An Orthogonal Frequency Division Multiplexing (OFDM) signal having a symbol defining a transmission unit is produced by dividing data streams into a plurality of carriers within a predetermined bandwidth and prepared with orthogonal modulation. A transform unit having at least two systems transforms the received OFDM signal to a carrier domain signal per symbol unit. A composite circuit segments the carrier units and adaptively composites the signal data which constitutes a plurality of different carriers transformed by a first system transform circuit and the signal data which constitutes a plurality of different carriers transformed by a second system transform circuit for each identical carrier in each system.

Orthogonal frequency division multiplexing (OFDM) receiver, OFDM receiving circuit and OFDM diversity reception method

An image information processing apparatus is described that suppresses noise generated in digital signal processing while preventing the circuit scale from enlarging. The apparatus includes a separator, a first detector, a second detector, a phase-locked loop, an A/D converter, a phase difference detector, a chrominance data processor and a luminance data processor. The phase difference detector detects a phase difference between the reference clock signal and the scan sync signal. The luminance data processor combines the luminance data in Units of two pieces to produce compensated luminance data in accordance with the phase difference.

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Iruma, Japan

Kunio Okada