Frequently Asked Questions



Q. Why fit a radar reflector?

A. Without a doubt it is important for safety to be seen on the radar of any vessel in the vicinity. For your boat to appear on a radar screen radar energy has to have been reflected from it, back to the radar antenna. To be reflected there must be mirror like reflecting surfaces geometrically aligned with the antenna. Unfortunately boats and ships are designed to have nice flowing single surface shapes. These shapes do not naturally provide antenna aliening reflecting surfaces. Indeed the author has had an experience where a tanker at close range disappeared from the radar screen of one of Her Majesty’s fighting ships for several minutes. Add to this modern radar invisible boat construction materials and the problem of radar visibility and detection becomes a large one.

Boats clearly are not good reliable radar reflectors. As it is in the boat users interest that his presence is advertised to other traffic, an enhanced radar signature is a very good idea. This can be achieved by installing an effective radar detection reflector. A radar detection reflector is specifically designed to provide many antenna aligning reflection centres ensuring a high probability of detection. A properly designed reflector will provide a consistent detection performance under all conditions and environments.

Q. Why do you consider the Blipper to be the best detection reflector on the market?

A. The Blipper has been deigned from scratch for the sole purpose of increasing the probability of detection by radar under all operating conditions. The computer simulation program SYNTAR showed that it was futile attempting to convert 1930’s technology reflector devices for the roll of detection. This clean sheet approach resulted in the Optimised Phase Modulating Helical Array. It has been developed using defence research radar technology and techniques. The array is so effective that it is embodied in some all weather defence systems.

It has been tested in the SYNTAR virtual environment to ensure that it will cope with all of the disabling effects of its operating environment. It is the only reflector available to be based on the Optimised Phase Modulated Helical Array concept, and actual tests conducted to Firdell’s own standards, (which are considerably more stringent than the official ones) confirm its extraordinary effectiveness across a wide range of operating conditions.

Q. What is an effective radar reflector?

A. An effective radar detection reflector is one that will provide a consistent reflected return above the threshold of detection under all operating conditions.

Q. How effective are Blipper radar reflectors?

A. The marine environment produces a number of operational conditions that severely degrade the effectiveness of radar reflectors. These include rain, multi path, radar set discrimination and motion related effects. The Blipper has been designed and developed to accommodate these effects using the SYNTAR computer simulation program. The program allowed all of the performance degrading effects to be explored and solutions established. The resulting design is the Optimised Phase Modulating Helical Array. It is the only reflector on the market professionally designed specifically for radar detection. The principles are unique and address all of the identified environmental performance degrading phenomena.

Q. What criteria should I use to choose a radar detection reflector?

A. Performance ease of Installation, boat friendliness, boat usage, aesthetics.
The detection Reflector must show a characteristic response as a large number of peaks of similar magnitude.There should be no critical gaps in the coverage over the full 360degrees of azimuth at all angles of heel.

The only way to see the true performance of a detection reflector is with a target pattern map.
Space is important to the installation of a detection reflector and as a general rule fit the biggest unit you can.

It should look better than a dustbin or oil drum.

Critical Gaps. A critical gap is defined as a square window of sides at 5 degrees, positioned on the Target Pattern Map (TPM) of the reflector with its sides parallel to the longitude and latitude directions, where the measured RCS is at no point above 2.5m². 

Q. How important is peak RCS

A. Unfortunately this is a big red herring. High peak RCS has little or no value in radar target detectability. However it can be claimed as a desirable performance indicator by the ignorant or unscrupulous device providers.

Q. What is a Target Pattern Map and is it important?

A. Yes, very much so. For a description and explanation please see our 'Target Pattern Maps' page on this site.



















Firdell Radar Reflectors Ltd. - Shirebrook House - Buxhall - Stowmarket - Suffolk - IP14 3DQ - United Kingdom