DIGITAL TRANSMISSION SYSTEM

摘要

PURPOSE:To increase a transmission capacity of an OFDM while minimizing the deterioration in a bit error rate characteristic due to the effect of crosstalk or the like and to attain digital TV broadcast within a width of a band of an existing-channel of a TV broadcast by selecting kinds of 8 or more signal points and sending data of 3-bit or more with one transmission symbol of a carrier. CONSTITUTION:A transmission data allocating current 13 for each carrier allocates a digital signal by one transmission symbol of data subjected to interleaving to plural carriers. Digital data allocated to each carrier are converted into a complex number in response to the bit pattern by a data generating circuit 14 on the frequency axis. The absolute value and the argument of a signal point on a complex plane correspond to the amplitude and the phase taken by each carrier. The frequency axis data generating circuit 14 applies octal phase PSK modulation to each carrier and 3-bit data per one signal point are sent.