Southcars reminds you to practice good computer hygiene when accessing websites and to protect your own computer and devices. An up to date firewall and virus program are a must before you access any webpages anywhere.

TIN PART 2 Links Coastal Radar and Waterfall Display Analyses:


Notice the antenna placement at water’s edge, mention of finding vessels and people at sea, and the ecological value of coastal radar at Link 67A:

Link 67A:


The goal of all this supercomputing of coastal radar data is to know what assets and risks exist by looking at ocean wave returns and temperatures. Additional input streams from other electronic surveillance methods may be combined with coastal radar by computer analysis.

Computer analysis is also used to process the radar return data to automatically eliminate unwanted echoes, impulses, RFI, and known ship profiles. Computer analysis also helps determine the best placement of the radar apparatus. See Sections B and A on pages 2 and 1 in that order in Link 67A-1:

Link 67A-1:


For a discussion of wastewater and water quality management applications of coastal radar, search for the heading of “Hazardous Materials Spills Response” and scroll down to the paragraph entitled “Water Quality Monitoring” at Link 67A-2:

Link 67A-2:


To avoid confusing the radar with ground returns from land surfaces, the coastal radars have to be located at the water’s edge. This is why coastal radars are built to be mobile and are frequently relocated.

Note the seaside coastal radar installation at the San Francisco Area National Park with the transmitting antenna in the foreground and the receiving antenna in the far background at Link 67A-3:

Link 67A-3:


Notice the antenna placement at water’s edge, and the ecological value of coastal radar at Link 67B:

Link 67B:


Ocean surface water movements are determined by ocean currents. If we collect data on surface currents, there is the possibility to track pollutants, provides critical information for search and rescue, monitor harmful algal bloom monitoring, aid maritime navigation, and assess ecosystems including land water effluents from land rivers opening out into the ocean. Even satellite assessment cannot provide the detail that coastal and digital near real-time radar returns can and do provide.

Because ocean waves are always present, there will always be a radar return image available for mapping of ocean currents. Continuous and frequent radar measurements and collection and storage of the returned radar data are important to current and future uses of the radar return data.

Pictures of a coastal radar installation in South Florida and an extended in depth documentation of Coastal Radar background, data management, and implementation are in Link 67C:

Link 67C:


There is an in-depth discussion of coastal radar spectrum management, frequency and time division multiplexing, modulation techniques, and call sign identification with center frequency and offset frequency assignments and coordination similar to our repeater coordination to avoid interference.

This document will also help us to understand what we see on the waterfall analysis displays and how they relate to the radar wave transmission.

Frequency assignment and radar modulation patterns are discussed at Link 67D:

Link 67D:


Tsunami detection and other marine threats are discussed by Professor Satoshi Fujii of the University of the Ryukyus in Link 68:

Link 68:


A map of the earth globe with radar and tsunami locations shown is at Link 68-1:

Link 68-1:


Coastal radar can also assist in ocean water quality monitoring and perform detailed environmental risk analysis.
The Southern California Coastal Ocean Observing System uses multiple input streams to assess ocean water conditions. A map showing the input sources including the HF radar sites in the green balloons along the coasts is available in full screen view.

Link 68A:


Significant effort is required to establish a workable and economical coastal radar screen of near shore and offshore radar returns.

The Coastal radar returns and the limitations on placement of the radar antenna are interesting and varied in how they are used and interpreted.

Freshwater placement of coastal radar historically has not been used because fresh water is a poor conductor of RF energy. Propagation of radiowave energy over fresh water is greatly reduced by the very poor conducting properties of fresh water.

Salt crystals in water increase conductivity. You can try this for yourself by placing electrodes connected to a light bulb in salt water and then trying it again in fresh water.

Because of the poor conductivity of fresh water, HF radar systems have rarely been deployed along large fresh water bodies, such as the U.S. and Canadian Great Lakes. Some research has been commissioned to determine how to make fresh water radar workable, with guarded results and recommendations for further research. See page 2 of Link 68A-1:

Link 68A-1:


See a history of the importance of Bragg scattering in coastal radar research in the section entitled “Background” and the subparagraph labeled “History” at Link 68A-2:

Link 68A-2:


An illustration of Coastal radar capability when combined with multiple input streams from other systems is at Link 68B:

Link 68B


An external view of a coastal radar installation in Japan is at Link 68C:

Link 68C


Inside the building are the transceiver, controller, processor, communications, and aerial switching consoles in custom built cabinets.

The aerial switcher and communications consoles are shown in Link 68D:

Link 68D


Also inside the building at the same operator position are the transceiver and receiver coastal radar units as shown in Link 68E:

Link 68E


Located off the end of the operator positions are the antenna coupler and switcher units as shown in Link 68F:

Link 68F


The part of the operator console positions closest to the coupler and switcher units as seen by the grouping of hanging microphones is shown in Link 68G:

Link 68G

Remote controller processors receiver and transceivers control units Coastal Radar.jpg



What does a radar return display looks like after a computer processes the signal. I still don’t have a good answer, but have a couple of guesses later.

For HAARPs, we can look at an ionogram from the more accurate digisonde.of a HAARP transmission at Link 69:

Link 69:


Many ionosounders have been replaced by newer "digisondes".

A smaller step in spectrum, say 25Khz instead of 100Khz, provides an improved detail in the signal return. as seen in Link 69-1:

Link 69-1:



Now we move from ionograms to waterfall display images.

There is an easy and excellent example of waterfall image of intermittent signals at Link 69A:

Link 69A:


Time to practice analyzing waterfall displays starting with an oscilloscope display and them move to a few Waterfall displays. See Link 69B:

Link 69B:


Now a Waterfall display of a single beacon like tone.

Link 69C:


Look at the time stamps on the left hand side of the waterfall display. Note how both the time mark and the waterfall image moves.

See if you can pick out all of the changes in the display when the tone switches to a higher pitch at 40 seconds in Link 69D:.

Link 69D:


Now, try to find the new minute marker at WWVH, the NIST time standard at Link 69E:

Link 69E:


Next compare the moving deep nulls on the right hand side with the slanted dark lines in the waterfall display as the time progresses at Link 69F:

Link 69F:


Paired emissions of different shifts in between frequencies. Note that with waterfall displays you may not need to hear the sound as much as see it. Notice the paired emissions at audio side bands on both sides in Link 69G:

Link 69G:


Listen for the sloped audio frequency and look for it in the waterfall display at Link 69H:

Link 69H:


More CODAR Radar:

Notice the use of the lower, upper, and double side bands to help analyze the waterfall in Link 69J:

Link 69J:


Try to analyze the next WWV transmission waterfall at the upper left of the screen, by looking at the waterfall without the sound on, when the receiver is tuned to a different frequency? No fair looking at the frequency display at the upper left. See Link 69K:.

Link 69K:


Because time is so important to radar returns and analysis, here is a waterfall display of an extra leap second in 2015. Look for the extra Leap second 2015 in the waterfall display at Link 69L:

Link 69L:


Tongue in Cheek Fun Quiz:

Now see if you can apply your new knowledge about high power radar, extraterrestrial communications, and waterfall displays to answer the following humorous questions at Link 82:

Link 82:


At 2:00 when they call the lunar base, were they using a ionospheric duct?
At 3:32, is the computer display waveform an OTH return?
At 7:29, was a HAARP duct required to communicate with the moon?
At 7:56 Is the copper colored coffee can on the radar antenna a feeder element
or is it the Chief W4RFJ’s forgotten coffeepot?

About 8:10 Is the antenna an OTH array or a direct return radar?
At 8:20-9:20 Is the RF exposure of the people standing in front of the radar within safe limits?