Ka band radar was introduced in the early 1990s and was originally used for Ka band photo radar systems. Ka band quickly was expanded into a Ka-wide band with a broader range of operating frequencies, the idea being that the wider range of possible operating frequencies would be more difficult to detect by radar detectors. Radar detector manufacturers quickly countered with products which would adequately detect the broader Ka-wide band frequencies. Thus the much broader Ka-superwide band range of frequencies was introduced around the mid 1990s in an effort to defeat radar detectors. Radar gun manufacturers then used some fundamental physics about the way that radar detectors operate. Radar detectors use superheterodyne technology which employs a generated reference frequency signal that is used to greatly boost the radar detector's ability to detect police radar. Thus some radar gun manufacturers chose to adopt Ka-superwide band radar frequencies which were higher harmonics of the reference frequencies used within radar detectors. Why did they do this? Because radar detectors also employ circuitry to filter out the reference frequency emissions from other nearby radar detectors. Radar detector manufacturers commonly referred to this technology as some form of "anti-falsing" technology. Obviously, if a radar gun manufacturer chooses a Ka band frequency which is a harmonic of any of the frequencies which a radar detector is designed to filter out in order to prevent false alerts from other nearby radar detectors, then the end result is that the radar detector ignore the Ka band radar gun frequency unless the signal was very strong. At that point the motorist would be well within the range of the radar gun. Radar detector manufacturers couldn't simply remove their filtering technology which reduces or eliminates falses from other radar detectors. Why? Because false alerts were and are the number one reason why people return radar detectors for a refund!

In any event, Ka-superwide band is now just simply called Ka band because many years have passed after all of the initial radar detector manufacturer's advertising hyperbole about their products' Ka-wide and Ka-superwide band detection capabilities. Thus, at the present time, there are only three radar bands which are used in North America – X band, K band, and Ka band which is really the Ka-superwide band. Some manufacturers claim that another radar band, Ku band (under K band), could eventually be used in North America. The problem is that Ku band, which is still used in some places in Europe, would mean a return to the old and bulky style of X band radar guns due to the Ku band operating frequency which is much closer to X band compared to K band. This just isn't ever going to happen because there is no way that police officers will ever want to return to using very heavy and bulky radar guns compared to their current K band and in particular their very lightweight Ka band radar gun systems.

What Are the Most Popular Ka Radar Frequencies, and How Do Radar Detectors Perform Against These Ka Radar Frequencies?

The 34.7 Ka band radar frequency is used by the most commonly deployed Ka radar gun models. This particular Ka band radar frequency is readily detected by all of the higher quality radar detector models available on today's market. Why? Because the 34.7 Ka is not a harmonic of the frequencies used within radar detectors! Thus this frequency is easy for a radar detector to detect since the radar detector's false alert filtering features don't apply to this particular radar frequency.

The 35.5 Ka band radar frequency is the next most popularly deployed radar frequency used in police radar gun models. Yet some radar detector brands have serious difficulties adequately detecting this particular Ka band radar frequency! Why? Because this frequency is a harmonic of the reference frequency used in other radar detectors, and since there is the need to filter this frequency since it may instead be radiating as a harmonic from another radar detector. All of the really innovative and practical electronic engineering solutions for this detection versus filtering problem have been patented by the top brand radar detector manufacturers – namely Bel, Escort, Whistler and Valentine Research. Quite simply, all other radar detector manufacturers simply face the choice of either allowing their radar detectors to alert to this frequency and at the same time also alerting to the presence of other radar detectors, or to simply reduce their product's sensitivity for what is the second most likely to be encountered radar frequency used within police Ka band radar guns. This is quite the quandary for copycat radar detector manufacturers who years ago never took their own research and development plus the filing of patents very seriously. Numerous innovative electronics design patents kept getting filed one by one by their competitors over the years. In essence the copycat radar detector manufacturers lost the radar detector war years ago, and there is no way that they can come back since all of the feasible solutions for radar detection versus the need for filtering out false alerts have been patented by their competitors years ago.

The 33.8 Ka band radar frequency is the least likely Ka band radar gun frequency to be encountered. This frequency also poses problems for radar detector manufacturers who wish to both detect 33.8 Ka band radar guns, yet also wish to prevent false alerts from some other radar detector brands and models. Nearly all of the radar detector manufacturers have had fair to exceptionally good success at designing their products to detect this least used radar gun radar frequency yet ignore harmonic signals from other radar detectors.

Conclusions

Only three radar detector manufacturers both hold patents and produce radar detector models which can consistently and readily detect all police Ka band radar gun models. All Bel and Escort (one and the same company) radar detector products consistently and accurately detect all police Ka band radar frequencies extremely well, yet manage to ignore false alerts from all other brand radar detectors in nearly every situation. Valentine Research's V1 product likewise consistently and accurately detects all police radar frequencies extremely well, but more frequently may temporarily detect emissions from other radar detector models. Whistler's higher end radar detector products consistently and accurately detect all police Ka band radar frequencies fairly well, and some of their higher end products also are extremely adept at filtering out emissions from other brand radar detectors. With these facts in mind, the potential buyer of a radar detector should look no further than the products offered by Bel, Escort, Whistler, and Valentine Research since all other radar detector brands and models will put the user at a serious handicap for detecting Ka band radar.

In testing by Carl Fors and Radar Roy two of the best performing Ka band radar detectors have been the Bel STi-R and the Escort 9500ix