The conductance of a first switch circuit is periodically controlled in response to an error-amplification circuit whereby electric power, stored in an inductance circuit from INPUT VOLTAGE VIN, is released, through a rectifier circuit, to a memory cell array for providing BIAS VOLTAGE VPP stepped up to a set voltage value. The base mat can be made out of any suitable material such as a polymer. The transmit beam pattern has a predetermined transmit beamwidth that is a function of the number of orthogonal transmit waveforms. The cutting implement is connected to and actuated by the actuator arm of an excavator. Also a method of controlling alighting arrangement is provided.