Broadband 60 GHz Sounder for Propagation Channel Measurements Over Short/Medium Distances

This paper presents a millimeter-wave propagation-channel sounder that uses an optical-fiber cable to achieve phase coherence between transmitting and receiving antennas using two modulated light waves in the vicinity of 1550 nm. In the described sounder, the optical-fiber cable approach permits a separation of up to almost 1000 m between the transmitter and receiver because of the low level of attenuation per unit length in a single-mode optical-fiber cable. The measurement system can sweep from 500 MHz below 60.1 GHz (59.6 GHz) to 500 MHz above 60.1 GHz (60.6 GHz) and proceed to 10 001 in-phase and in-quadrature propagation channel measurements in <formula formulatype="inline"><tex Notation="TeX">${\sim}{\rm 5}~{\rm sec.}$</tex></formula> Measurements of the frequency response of nonline-of-sight and line-of-sight indoor/outdoor propagation channels over medium <formula formulatype="inline"><tex Notation="TeX">$({>}{\rm 100}~{\rm m})$</tex></formula> and short ranges can be performed for two or more different lateral receiving antenna positions for antenna diversity studies.