During WW2, the use of the RADAR apparatus was only known to by the military, both the Allied and the Axis. At the end of WW2 the use of RADAR proliferated, whereby overnight, it practically became a household name.

The International body, which globally controls and regulates these types of emissions is called the International Telecommunication Union (ITU), and is based in Geneva, Switzerland. The ITU, which operates with many countries of the world sets the international policy and safety standards for Radar operations and other communications.

Aside, from an International governess, most countries have a their own indigenous program in place as well. Here in Canada, this is controlled by Industry Canada and falls under the Directorate of Frequency Spectrum Management and Telecommunications or DFSM. This directorate, whose radar protocols are harmonized with those of the ITU, controls the transmitting, licensing and allocation of devices to be used in Canada.

Navigational Radars are required to be designed to be within the optimized operating parameters indicated in the table below. Military purchased Commercial-off-the-shelf applications often see a civilian radar being militarised to fit their requirements. This process often incorporates a name change as well. For example, a Furuno 1830 radar, may be renamed while in its military service to a AN/SPS-XY or XYZ. This re-codifying is primarily for logistics reasons, however, the impact on an EW‘s understanding of the Electronic Order of Battle (EOB) can become far more complicated, especially if the radar is common between both hostile and friendly forces. The need to avoid fratricide exponentially increases.

One could imagine the impact on an EW operator monitoring the spectrum while in a dense shipping lane like the English Channel or the Malacca Straits. Off with the headset!

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Navigational radars can be found to operate on many different types of sea-going vessels. They are also used in land-based applications such as Coastal Search, Vessel Traffic Services or even landlocked universities or testing facilities that cover radar as part of their science curriculum.

Above is a typical India Band (I-Band) navigational radar of the Furuno Radar family, its transmitting antenna, and a operator workstation which displays/presents the radar’s contact information. Depending on the vessel's size, these radars may be integrated as a combination of both an E-Band and I-Band radar or as twins. These may operate independently or be slaved together to provide both a long and short range picture.

EW Reprogramming

In the Specifications image below, the navigational radar’s operating characteristics are often published in the specifications portion of the Radar’s users manual. The “mean” pulse information is related to the desired range scale that is selected by the Radar operator. This pulse information is important to an EW operator as it provides them the nominal operating characteristics of the radar. These characteristics can then be reprogrammed into the EW’s Intercept equipment libraries and aid the EW operator upon intercept.

When reprogramming Electronic Support equipment, tolerances are additionally added to each of these means to assist the EW operator in hopefully matching the captured radar upon intercept. Over time, intercepts for this type of radar, that are properly correlated and collected, may vary its reprogrammed view or show that the radar has certain unpublished characteristics, or is operating out of tolerance. A concentrated effort in collection exponentially helps ones understanding of the spectrum and additionally allows the possibility for the radar to be redefined and captured effectively in the next library cycle.

Navigational Radars are produced by a broad range of manufacturers with names like Racal, Sperry Marine, Decca, Furuno, Raytheon, Atlas and Bridgemaster, to name a few. The list keeps growing and growing. Today's systems are very human factored and are always improving, however, their operating characteristics are still refined to the table above.

Derived Radar Modes for Reprogramming

Below are the typical radar modes derived from these specifications:

* The Scan Type is Circular and is based on the transmitting antenna which moves in a 360 rotational clockwise pattern. The RPM has been converted to seconds to easily determine how many times a second the antenna is rotating.

** Often upon intercept, the EW operator may quickly determine the other modes of operation of the same radar, if the Radar Operator changes his range scales while being detected. The transmitting frequency would remain the same, however, the PRF, PW and Scan time values will change if the Radar operator migrates to range scales that employ these specified value changes when selected. This can be true for any type of Radar that employs a fixed frequency.

EW Intercept Station - Click Image to Enlarge

The intercept station above depicts the IP-480 Analysis screen of the AN/WLR-1C. Along with the audio

provides an example of what an EW operator may see on their scope when listening to the intercept.