To increase the transmission efficiency drastically by increasing the number of combination patterns of code words that are available in one communication unit consisting of pluralities of time slots.

A primary modulation matrix of a combination pattern formed by setting three or less combination pairs corresponding to the order of time slots T1-T7 among combination pairs of prescribed frequencies f1-f8 and prescribed phases (0, π=p0, p1) is cross-referenced with a bit pattern in a prescribed bit unit of digital data to be inputted. A modulation signal with a prescribed frequency and phase denoted by the three or less combination pairs is generated, based on one primary modulation matrix corresponding to the bit pattern selected per prescribed bit unit of the inputted digital data based on the cross reference. Then the generated modulation signal is subject to spread modulation for each time slots based on information of the frequency hopping spread code series.