Disclosed is a method and an apparatus for generating a preamble sequence for an adaptive antenna system supporting a space division multiple access in an OFDMA communication system. The valve includes a seal module having a proximal end and a distal end with a lumen sized to allow the passage of fluids or gases. The system can also include an integrating chamber that collects the light that is not transmitted through the bandpass filter unit and is substantially reflected, and redirects this light to strike the filter unit again, resulting in a significant increase in the optical power passing through the filter. The analog outputs are output on the monitor attached to the KVM switch.