Popis: |
This paper describes the development of a very flexible multi-antenna testbed built on 5 PCBs. The FOM testbed (FOM, Flyable OFDM MIMO) was built with off-the-shelf components and can be configured with any number of antennas at the transmitter and receiver with a maximum of eight antennas on each side. The FOM testbed is dual-band with the two carrier frequencies at 2.44GHz and 5.245GHz and a bandwidth of 25MHz. It implements a digital IF scheme to mitigate I/Q mismatch and a DDFS for fast channel hopping. Such a flexible testbed becomes essential for evaluating various communication schemes for broadband applications. Theoretical studies and simulation can be validated on this testbed in a real-world environment with a real wireless channel and hardware impairments. A powerful GUI was developed for the operation of the FOM testbed. The architecture of the FOM testbed and the details of the circuits implemented on the individual PCBs are presented. The calibration process of the FOM testbed is discussed. Finally, possible applications such as MIMO transmissions or cognitive radio are discussed. |