POWER LINE COMMUNICATION OPERATING FREQUENCY BAND SELECTION APPARATUS, SYSTEMS AND METHODS

摘要

A band of interest is divided into band segments. A scan frame is sent by a transmitter at a transmitting PLC node across each band segment. A receiver at a receiving node scans the band segments, listening for the scan frame. Upon detecting a scan frame, the receiving node measures the signal quality of each OFDM subcarrier modulated with symbols from the scan frame. The subcarrier signal quality values are stored in a table. Upon completion of the scan process, the table contains a signal quality value for each subcarrier within the band of interest. The table is then analyzed to find an operating band consisting of subcarriers with a highest average signal quality or a band that results in greater than a pre-determined minimum signal quality. The invented methods and embodiments may operate periodically to readjust the operating band configuration in the presence of electromagnetic interference including time-variant interference.

主权项

1. An orthogonal frequency division multiplexing (“OFDM”) power line communication (“PLC”) apparatus, comprising:
a negotiation receive mode band segment selector in a receiver coupled to PLC interconnect conductors at a first PLC node to scan a total of M negotiation mode band segments BS1, BS2 . . . BS(M) within a band of interest by selecting at least one set of Q subcarriers {K}={K(1) . . . K(Q)} at a time, each set of subcarriers {K} associated with each of a number N of the M band segments across which an identical scan frame may have been transmitted over a communication link by a transmitter at a second PLC node; a signal-to-noise ratio (“SNR”) calculator communicatively coupled to the receive mode band segment selector to determine an SNR value S(j,q) for each selected subcarrier K(j,q) for which frequency domain symbol information is detected, j being an index indicating the negotiation mode band segment and q being an OFDM signal subcarrier index; an operating band analyzer communicatively coupled to the SNR calculator to analyze SNR values S(1,1) . . . S(M,Q) associated with the subcarriers K(1,1) . . . K(M,Q) across the band of interest and to determine a lowest-frequency subcarrier K_START and a highest frequency subcarrier K_STOP associated with an operating frequency band FB_OP such as to maximize an average SNR for communication across the link.