Abstract: A spectrum spread communication method includes a step of generating a data block formed by a plurality of M bits of transmission data in the CDMA communication method, a step of modulating an orthogonal sinusoidal wave by the repeated series of the data block to generate a spread symbol, a step of transmitting the symbol, a step of performing reverse spread of the reception input by using the orthogonal sinusoidal wave, thereby completely isolating the multi-user component including the multi rate.

Abstract: A parallel sampling device comprises a memory that stores the values of the sampling function (Sin ?t/?t), a low pass filter, sampling means that samples a signal, which has passed through low pass filter, at a sampling period of Ts, and parallel sampling means provided in a stage following the sampling means. The parallel sampling means generates parallel sampled values at an interval of the sampling period Ts/N(N is a natural number equal to or larger than 2) based on sampled values obtained by the sampling means and the values of the sampling function stored in the memory. This configuration allows parallel sampling to be performed easily even if the frequency is high or the sampling period of parallel sampling is narrow.

Abstract: In a communication method for transmitting a multipath characteristic measurement signal and a plurality of data transmission signals, the multipath characteristic measurement signal and data transmission signals are a signal array formed by a plurality of coefficient matrices that are orthogonal to one another within the matrices and which comprise at least one coefficient array that is common in the column direction or row direction. The multipath characteristic measurement signal formed by the coefficient matrices is the same signal array formed by the one common coefficient array.