Teledyne Lincoln Microwave (TLM), a Teledyne Defense Electronics Business, has introduced a new high-performance X-band radar receiver sub-system assembly for use in ground-base surveillance radar applications. The company worked in conjunction with low noise amplifier, circulator/isolator and coupler designers to create the headroom necessary to introduce additional functionality to improve this sub-system’s overall performance.
Teledyne’s new design relocated the radar’s receiver sub-assembly from the air-conditioned cabin to the antenna. Enabling the receiver to be positioned on the antenna demanded that the sub-assembly meet a constrained and complex space envelope as well as a challenging weight budget.
Reliability was recognized as a critical issue to address. When operational, the radar installation would be unmanned with planned maintenance activity minimized. Any unplanned maintenance would be costly, with an unacceptable impact on system availability.
Additional Design Considerations:
• Control of heat dissipation
• Environmental durability
• Waveguide pressurization
• Minimization of loss attributable to cable interconnects and waveguide interfaces.
The improved performance was made possible by first identifying a number of small reductions in the sub-system’s insertion losses. A significant contribution to this was made by exchanging an off-the-shelf, connectorized LNA for a Teledyne Lincoln Microwave LNA with waveguide input. This eliminated the requirement for a waveguide to coaxial adapter. The LNA waveguide interface was later customized to enable the component to be located in the available space envelope.
This afforded the design margin necessary to enable the inclusion of an isolator at the output of the limiter; the isolator stabilized the low noise amplifier performance and thereby made it possible for the specification of the limiter to be eased.
Once the cascaded noise figure analysis was complete and the line-up defined, other sub-system issues were addressed. Foremost amongst these was the design of a mechanical layout to meet the dual constraints of a complex space envelope and a challenging weight budget.
The solution was found in adding customized interfaces to our standard components, including the LNA. This resulted in the unique structure seen in the image which remained within the available weight budget.
Other mechanical considerations included locating the limiter’s field-replaceable gas switch in an accessible position, thereby facilitating in-service, in-situ maintenance to maximize system availability.
During acceptance testing the resultant sub-system solution outperformed the target specification, validating the customer’s decision to enhance its system engineering capability by utilizing the specialized component expertise of the Teledyne Lincoln Microwave team.
Click here to learn more about the new X-band Surveillance Radar from Teledyne Lincoln Microwave.
