Exploring Ping Pong Channels at THz Frequencies

This paper experimentally investigates the ping pong channels resulting from a narrow but divergent beam of the horn antenna as witnessed in non-line-of-sight (NLoS) scenario for the 240–300 GHz frequency range. A THz vector network analyzer (THz- VNA) extender measurement setup equipped with a ~ 25 dBi horn antenna as transceiver (TRX) is employed to retrieve and evaluate the reflections prompting a ping pong influence on THz wireless channels. This ping pong effect being uncommon at lower frequencies is studied from extensive measurement campaigns for monostatic measurement setups in the frequency range of interest. Corner reflector (CR) as well as metal plate reflectors (MRs) are employed to analyze the resultant ping pong channels in the manifold scenario setups. This ping pong effect may lead to an irreversible ambiguity in the channel transfer functions (CTFs) and certainly demands understanding of such sub-harmonics.