A pet crate having a top, a bottom, and a cage between the top and bottom. In one or more embodiments, a mobile computing device may be arranged to support quad-band GSM communication in the GSM-850, GSM-900, GSM-1800, and GSM-1900 frequency bands. A controller enables the beam tilt of a number of antenna at a site to be remotely varied. The first two-dimensional sensor may be positioned across the tracking ball and opposite to the user-accessible touching area. In this manner, the encoder may indicate to a decoder the proper syntax decoder to apply to the coded unit. An integrator integrates the voltage value computed by the voltage computation unit for each received symbol for the respective symbols corresponding to the \u201csignature\u201d.