Wide-band terahertz communication at ambient atmosphere

Abstract

Communication band becomes more and more crowded, terahertz (THz) technology can obtain more than 300GHz frequency, and easy to obtain the transmission rate of Gbit/s. This paper reports a kind of wide-band THz communication based on a THz time domain spectroscopy (TDS) system, which uses photoconductive antenna as a THz source, ZnTe crystal as a receiver. In our experiment, the modulation mode is the on-off keying (OOK)[1] method based on amplitude-shift keying (ASK) [2].An audio signal was generated by program, and we put the signal into a voltage amplifier and increase the peak-to-peak voltage, which was used as a bias voltage on the photoconductive antenna. Then the signal to noise ratio of the received audio signal is 51.4. The wide-band terahertz communication on ambient atmosphere was demonstrated on a THz time domain spectroscopy system. The received signal has the same spectrum with the original audio signal, but noisier than the original signal. Fig.1. (a) Time domain waveform of received audio signal with the frequency of 2000Hz; (b) Spectrum of the original audio signal; (c) Spectrum of the received audio signal.