High Linearity, High Dynamic Range RF Receivers: A monolithic chip is under development to enable operation of GPS receivers in the presence of jamming sources. This technology is very enabling in the context of hand-held applications and GPS guided munitions, in which a compact design is of the essence.

The NTK-Ironman-01 is a complete dual-channel global positioning system (GPS) front-end down converter. This low power CMOS IC integrates a low-noise amplifier (LNA), image rejection mixer, automatic-gain-control amplifier (AGC), secondary mixer, and clock buffer. External IF, baseband filters, and ADCs enhance flexibility. The device supports C/A, P(Y), and M codes.

This device provides the most versatile integrated front-end available. Two independent down converters per channel (shown below) gives it a wide range of supported frequency plans. Each mixer utilizes an independent external COTS synthesizer to generate the local oscillator (LO). Further, each down converter can be used for high side or low side mixing and operate on L1 and L2 simultaneously. Alternatively, both down converters can operate only on L1, L2 or L5, as is necessary when used with an adaptive antenna array.

The digital AGC allows the receiver to accommodate multiple wideband and narrow band jammers having a total power up to -13 dBm without clipping.

The device supports multichannel digital adaptive anti-jam signal processors providing wideband cancellation in excess of 50 dB. When combined with a GPS signal processor providing 70 dB A/J the RF ASIC will support GPS tracking with 120 dB J/S.

Dual-channel GPS front-end diagram. Multiple 2-channel chips can be used in a single receiver.

Clock Synchronization: A chipset that will synchronize a large number of clocks to ps resolution is under development. A standing wave approach is used to keep the clocks synchronized. This solution is most suitable to backplane applications.

Backplane application with standing wave clock synchronization.