CDMA
Another alternative would be a CDMA (Code Division
Multiple Access) based system. The Qualcomm developed technology is currently
used in many wireless phone networks in North America, most prominently by Verizon Wireless and Sprint PCS. The technology, in general, works by having
many simultaneous transmissions over a single wide band channel. Each
transmission is assigned a unique code so the receiver is able to distinguish
each individual transmission. All other transmission would be regarded simply as
noise. For the PSU, a CDMA receiver could be placed in each PSU, and only look
for the unique code assigned its companion seat. It would allow for a single
channel to be used for the entire plane, without having to worry about
destructive interference from other seats.