An SDR platform for performance evaluation of OFDM-based indoor DAS solutions

摘要

In this paper, we present a software defined radio-based platform created using LabVIEW and USRP 2920 in order to emulate a distributed antenna system (DAS) setup within an indoor LoS environment. In the proposed test bed, two USRPs are interconnected by MIMO cable and communicate with a single USRP receiver. The two transmitters are used to emulate two spatially separated OFDM transmitters by varying their relative transmit gain configurations. The starting transmission times of the two OFDM transmitters are also varied in order to model the relative delay between two DAS antenna signals due to variation in propagation delays over the feeding network. Measurement results for numerous emulated DAS configurations reveal that the difference in propagation distance between DAS antenna over the feeding network can have significant impact on BER performance even with the employment of the standardized cyclic prefix.