An experimental study of a sub-THz continuous wave generator based on photonics without an optical source

A sub-THz continuous wave (CW) generator based on photonics without an optical source is proposed to make an oscillator within sub-THz frequency bands. Comparing with a conventional sub-THz generator based on photonics with the optical source such as double sideband suppressed carriers, we have generated the optical sidebands separated with a wanted sub-THz frequency and photomixed them to make the sub-THz CW. In order to implement that, an optical feedback scheme with an erbium doped fiber amplifier (EDFA) is used. From measurement results, the sub-THz CW output power is 2 dB higher than that of the conventional sub-THz generator. Consequently, the proposed technique is very useful for cost effective and stable sub-THz CW generator to stimulate research activities in the sub-THz bands.