A traveling wave amplifier based on composite right/left handed (CRLH) transmission lines periodically loaded with resonant tunneling diode pairs

This paper proposes a traveling wave amplifier based on composite right/left handed (CRLH) transmission lines (TLs) periodically loaded with resonant tunneling diode (RTD) pairs. This TL can be regarded as a “lossy” TL with a negative loss because of the negative differential resistance of the RTD. This means that the TL can amplify signals while the signal travels along the line. One of the most important points to be investigated to realize this amplifier is the stability of the circuit. We discuss stability of the TLs periodically loaded with RTDs, and show that they can be stabilized by using CRLH TL configuration. It is demonstrated that this amplifier can have a gain for wide frequency range.