Abstract: A position display system using wireless mobile terminals for determining the route to be taken by a traveler is provided. The system utilizes information provided by the traveler such as the destination path, and other information for determining a fortune-wise optimal route, or for determining an azimuth or the lucky azimuth of destination.

Abstract: In a demodulating method of demodulating amplitude-demodulated signals in an amplitude phase shift keying system for conducting an amplitude modulation by setting signal points as information codes on a complex plane representing a signal space of transmission signals onto circumferences of two concentric circles including a first circle having a first diameter and a second circle having a second diameter smaller than the first diameter on the complex plane, there are obtained, in accordance with an amplitude value of an amplitude component of each symbol of a received amplitude-modulated signal, a first threshold value and a second threshold value having a predetermined relationship with the amplitude value.

Abstract: Method and apparatus for transmitting an information signal generate a plurality of block signals on the basis of the information signal, generate a plurality of parity block signals on the basis of the plural data block signals, generate a frame signal containing the plural data block signals and the parity block signals, and send out the frame signal. Each of the data block signals includes a first block synchronizing signal indicating the start of the data block signal, a data signal containing the information signal and a first parity signal derived by encoding the data signal. Each of the parity block signals incudes a second block synchronizing signal indicating the start of the parity block signal, a second parity signal and a third parity signal. Bit signals located at same bit positions in the respective second parity signals are derived by encoding bit signals located at the same positions in the respective data signals.

Abstract: A digital signal transmission using OFDM modulation scheme in which the valid transmission data can be reproduced without requiring a recovery of the carriers at a receiver side. On a transmitter side, the transmission data sequence in which predetermined reference data for each carrier are placed among valid transmission data is modulated according to an orthogonal frequency division multiplexing (OFDM) modulation scheme using a plurality of carriers and obtained OFDM transmission signals are transmitted. On a receiver side, the received OFDM transmission signals are demodulated to obtain received data sequence containing valid received data and received reference data, and the valid transmission data are estimated from the received data sequence according to the valid received data, the received reference data, and the predetermined reference data for each carrier.