Terahertz communications using resonant-tunneling-diode oscillators

The recent progress in terahertz wireless data transmissions using resonant-tunneling-diode (RTD) oscillators is reported. RTD oscillators with wide modulation bandwidth (~30 GHz) were fabricated, and wireless data transmissions in the 500-GHz range were demonstrated. An error-free transmission data rate up to 22 Gbps and a transmission with bit error rate less than the forward error correction limit, up to 34 Gbps, were achieved. For alignment-free wireless communication in the polarization direction, an RTD oscillator integrated with a radial line slot antenna for circular-polarized radiation was proposed and fabricated. A sharp directivity and low axial ratio of polarization (2.2 dB) was achieved at 710 GHz.