The GP2021 is a 12 channel C/A code baseband correlator for use in NAVSTAR GPS satellite navigation receivers. The GP2021 complements the GP2015 and GP2010 C/A code RF downconverters available from Zarlink Semiconductor. GP2021 is compatible with most 16 bit and 32 bit microprocessors, especially those from Motorola and Intel, with additional on-chip support for the ARM60 32 bit RISC processor. When the ARM60 is used, the on-chip memory management functions allow implementation of a full GPS receiver with minimal external logic.
The GP2021 allows individual channel de-activation, for systems not requiring full 12-channel operation, to save power and processor loading. Receiver power may be further conserved by reducing the supply voltage to 2.2 V under battery backup. Although all system functions are disabled, the 32.768 kHz oscillator and Real Time Clock are maintained for the microprocessor to estimate satellite visibility at power on to reduce signal acquisition time.