Coding High Frequency Radar - Isis Project No 282

Radar device which can produce a code or information of a given object within the return signal to the original transmitter. The invention can be used for the detection, tracking, positioning and identification of a given object, with reduced power consumption.

Planar retroflection

The Oxford technology consists of a device, a planar retroreflector, which reflects microwave signals back to their source, with little energy lost in reflecting the energy in undesired directions.

Applications

• Search and rescue
• Traffic management
• Positioning and tracking of airborne and marine assets (including lighthouses and harbour control systems)

Demand

Radar is important in not only detecting a given object, but also in identifying and providing information. There is a need for the given object to automatically provide routine data relating to its type, position, speed etc. with as low a power requirement as possible.

Advantages of invention

• Passive and robust method
• Signal returned to illuminator is far greater than simple reflectors
• Signal maintained over extremely wide angles of incidence
• Single printed circuit assembly provides cheap and unobtrusive unit
• Reduced levels of radio pollution
• Return signal modulated to provide a means of transmitting data

Since the microwaves are retroreflected, rather than re-transmitted, the only electrical power necessary is that required to drive the optional active modulation switches. This low power may be achieved by a modest power source, or scavenged from the illuminating signal.

Limitations of other retroreflectors

• Passive retroreflectors struggle to establish a communications link
• Active transponders can be costly and power hungry. In addition, they are non-directional, enabling other receivers to intercept the information while also causing environmental radio pollution

Patent protection

This technology is covered by granted patents in key global market areas, and Isis would like to discuss the licensing of the technology with interested companies. Please use the link below to contact the Technology Transfer Manager.

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