11. Unregulated radio frequencies transmit short-range signals across a network consisting of 5-foot-high receiving antennas . 12. There is an electrical relationship defined by the distance between transmit and receive antennas . 13. The power lines can also act as receiving antennas , and receive interference from radio signals. 14. Positioning receiving antennas away from electronic equipment helps to reduce the effects of local interference. 15. On the transmitter side, a second transmit antenna is installed somewhere below the receive antenna . 16. The transponder then transmits its unique identification number to a receive antenna in a mat. 17. In order to maximize the throughput in multiple receive antenna systems, multi-stream transmission is generally required. 18. As a result, a single CFO set is to be estimated for the multiple receive antennas . 19. This configuration delivers similar performance to the case of two receive antennas and one transmitter antenna. 20. At each receive antenna , the cross-correlation between the received Signal and the known preamble is examined.