RoF system experiment with 60 GHz carrier frequency and IQ data modulation

In this paper, a comprehensive examination of 60 GHz RoF system with IQ data modulation is presented. An efficient RF upconversion setup has been implemented to generate the 60 GHz carrier by optical means. An automation system under python environment was created as a tool to ease the characterization process. The setup is evaluated in terms of RF frequency, RF power, and carrier to noise ratio. The measurements assured in a clear way the applicability of the RF upconversion stage for the whole ISM band. In the data modulation stage, an optical IQ modulator (Dual parallel MZM) is employed to generate a complex modulated data format such as QPSK for different data rates reaching to 10 Gb/s. In order to minimize the chromatic dispersion as well as the bit walk-off effect, a customized Mach Zehnder interferometer (MZI) was introduced to support the OSSB format. The IQ modulated RF signal is detected, amplified at base station (BS) and transmitted to the mobile unit (MU) which has been manufactured in our lab. The received signal by MU has been down converted and demultiplexed. The two I and Q channels are sampled, stored by real time scope, and exported for further offline processing. Two antennas, horn for transmit and patch array for receive, are employed to establish a wireless link between the BS and MU. The wireless link is characterized in terms of carrier frequency dependency. A V&V algorithm for phase recovery has been applied on the received data for synchronization purposes. Error-free transmission could be demonstrated.