A portable therapeutic device and method of use generate longitudinally propagating ultrasound and shear waves generated by such longitudinally propagating ultrasound to provide effective healing of wounds. The light control system and apparatus may be utilized with various lighting fixtures. The multiple elongated drain regions are formed so that they are each electrically isolated from each other on the compound semiconductor layer. The assigned resources may include multiple tiles, with each tile corresponding to a block of time frequency resources. In addition, a sniffer port selected among the plurality of ports is identified as a transmit port to provide output of data packets received or transmitted by multiple sniffed ports.