What GAJT Does

GAJT is a null-forming antenna system that ensures satellite signals necessary for computing position and time are always accessible. It comes in versions suitable for land, air, sea and fixed installations.

The technology provides anti-jamming performance comparable to much larger systems, but at a significantly lower cost. Easily integrated into new platforms, GAJT can also be retrofitted with the existing GPS receivers and navigation systems on existing and legacy military fleets.

Schiebel’s Day says, “GAJT mitigates interference from electronic jamming sources by electronically changing how the GPS receives the GPS signal. It effectively switches off that part of the antenna that is being jammed, leaving the rest of the antenna available to receive the GPS signals and allowing the system to operate.”

Soar explains that the performance of a system is the sum of the power cancellation from the anti-jam system—GAJT’s datasheet performance is 40 decibels of cancellation—plus the cancellation benefits of other elements of the system such as the receiver itself.

The commercial “off-the-shelf” nature of the company’s products allowed NovAtel to quickly deliver the requested GAJT-AE-N antenna control units, along with four-element Controlled Reception Pattern Antennas (CRPAs).

Soar says at least part of the credit for NovAtel’s swift action should go to the Canadian Government. GAJT is subject to the Controlled Goods Program of Canada.

“That means we needed an export license,” he explains, “the efficiency of this process made it clear to us that, in addition to protecting the national interests of Canada, the government is also committed to supporting its allies and industry by acting as swiftly as possible when necessary.”

“All of the integration work, the GAJT and the CRPA, was done by Schiebel, Soar says, “with a little telephone and e-mail support from NovAtel.”

In fact, this is a key selling point—GAJT is designed to be retrofitted. It works with any installed GPS receiver, whether it is a special encrypted military GPS receiver with a Selective Availability Anti-Spoof Module (SAASM), a precision or survey receiver such as the NovAtel OEM628, or even a simple mass-market receiver.

The NovAtel material was cost effective, lightweight, and easy to install, says Day. “And we greatly appreciated NovAtel’s ability to respond to technical issues and rapidly deliver the hardware.”

The end result was a quick turnaround, with Schiebel’s customer able to quickly re-deploy the newly fitted CAMCOPTER® S-100 within a minimal timeframe.