Unlike earlier methods and systems in which Radio Link Control performance was characterized in terms of the throughput, and the size of the higher layer Protocol Data Units or packets to be transferred was ignored, a method and apparatus is provided that is based on the delay of a higher layer PDU or packet. The database has a plurality of data records and is coupled to the data event agent. The subject invention also relates to processes for making such compounds as well as to intermediates useful in such processes. A load circuit 3 includes a polyphase current-to-voltage conversion circuit for converting a current value of the polyphase phase-shifted current signal Co into a voltage value, and outputting an output signal Vo.