A method and apparatus are provided for reducing the number of pilot symbols within a MIMO-OFDM communication system, and for improving channel estimation within such a system. The method comprises defining a key generating key within the remote keyless entry device, and using that key generating key to generate a working key. Through the process, computer readable definitions of an alternating aperture, dark field phase shift mask and of a complimentary mask are generated. The encoder is configured to divide the readable spectral range into a plurality of bins. The state of the contact signal is periodically sampled for a predetermined period of time and the number of samples for which the contact signal was high are counted. The system includes a liquid dispensing machine having a dispensing area capable of receiving a container, a scanner adjacent to the dispensing area, a container that is capable of being placed in the dispensing area, and annular barcode indicia extending around an exterior surface of the container and centered around a generally vertical axis of the container.