Parallel Channel Receivers

The parallel channel receiver locks onto different GPS satellites simultaneously, and provides un-interrupted signals to the GPS processor. Due to continuous tracking of the satellite signals, the accuracy and time to lock on to the satellite signals are better compared to multiplexing receivers. Atleast four hardware radio channels are required for continuous operation. . Recent GPS receivers have sufficient hardware radio channels (upto 12) to lock onto all the satellites that happen to be in view at any time.

Multiplexing Receivers

The multiplex receiver switches between satellites being tracked, thus establishing a temporary contact with one or two satellites and switches to other satellites to get the information required. Since a multiplexing receiver locks on to a satellite for only a short amount of time, they tend to be less accurate than parallel channel receivers. On the otherhand, parallel channel receivers lock on to a given satellite, and stay with the same as long as required. The signal acquisition process (also called triangulation) is said to be better with parallel channel receivers. A 12 channel parallel channel receiver will be able to simultaneously track up to 12 satellites in the orbits.