Provided is a chip scale marker and a marking method. A mobile unit receives testing location information, including the cell location data and the boundary information, from a network element. The amplifier can include separate feedback loops: an external relatively lower speed feedback loop for controlling signal path bandwidth, and an internal relatively higher speed feedback loop for controlling output impedance bandwidth of the linear amplifier. The signal transmitted by the radio unit may include an indication of a status of the vacuum sewer valve. The method further comprises determining one or more additional keywords based on the evaluating. The invention concerns workload compression which helps improve the scalability of such applications.