When signals from GPS satellites reach the Earth, they are at very low levels, often well below the noise floor. The receiver can recover the signal, but it is vulnerable to interference or jamming since the power levels involved are often many orders of magnitude greater than the GPS signal. Cobham Antenna Systems has recently introduced two new Digital Antenna Control Units (DACU’s) for improved performance.
The DACU is the interface to the antenna unit. It mitigates narrow-band interference, using an excision process, and broadband interference by creating directed nulls in the antenna pattern. These techniques provide significant anti-jam protection even in highly dynamic, multi-jammer environments.
The two new units are the type 7-6005, four channel unit, and the type 7-6008, eight channel unit. Both DACU’s operate with L1 and L2 band antennas.
Completing the new product line up is the type 20-7009 four element Controlled Reception Pattern Array (CRPA) antenna. The 20-7009 consists of four light-weight, temperature stable radiating elements which operate with nominally hemispherical coverage in the GPS L1 and L2bands. The array is available in a variety of options, including passive and active configurations.
The active configuration contains four low-noise amplifiers protected by filters, providing rejection of unwanted out-of-band signals, and limiters which provide protection from high power signals. For more information about these, and other GPS anti-jam solutions, please contact Maser Defence at [email protected]

7-6005