Hello All,

Most of you are aware that we distribute an active radar target enhancer
product on our commercial website.  The units are manufactured in the United
Kingdom and are intended to answer many of the shortcomings discussed in
this thread.  Besides ours, there are several competitors.

Basically the active units receive a radar pulse, run it through an
amplifier section and retransmit the pulse back in an omnidirectional
pattern.  The advantages of the active radar target enhancers are: 1. Size;
they take up very little room on the masthead. 2. Aesthetics; being small,
they don't look like a giant wart on the top of your mast.  3. Survivable;
They have much less surface area and are less likely to be carried off by
the wind 4. Ease of installation; all the units are a snap to install with
the main task being the necessity of running a multiconductor cable between
the helm station and the RTE antenna.  There are several disadvantages.  1.
Cost; they are much more expensive than corner reflectors.  2. Power
requirements. While they draw 650 MA of current when transmitting and less
than half that when in a quiescent state, they do consume power.  3. More
complex installation. 4. Only operate on the dominant X band, no S band
units out there to the best of my knowledge.

They have a couple other features that corner reflectors don't have.  They
notify you when you're being painted by radar with either a visual alarm, an
audio alarm or both.  They increase RCS by a meaningful amount regardless
of their orientation to the sea or the painting vessels transmitter.

Radar horizon is still a factor.  The higher the unit above the sea, the
further it can "see".  Can't fight physics.

This is a UK regulatory issue and we can't sell the units over there.  There
are a number of UK based dealers.  However, we ARE affiliated and do have
both an interest and a bias so our disclaimer is limited.  We mainly sell to
the gov't and research vessel markets that put these things on RIB's so they
can track the little critters while they zoom about away from the mother
ship.

Someone asked the question if another vessel could "see" your radar when it
is transmitting.  The short answer is no, each radar unit can only "see"
itself.  They are narrowly tuned and sometimes uniquely coded because a
radar set can only deal with timing the arrival of their own return pulses.
If they were wide open to all radar pulses, the radar unit could not
discriminate between its own pulses and another vessels pulses.
Consequently, they would be unable to function.

Reflective Regards to All,

Frank & Claudette Weismantel
Elverta, CA
Boatless for a little while longer
<SNIP>

Frank did an excellent job of  describing the active radar transponder that
enhance your RCS.

He also  explained this:
Someone asked the question if another vessel could "see" your radar when it
is transmitting.  The short answer is no, each radar unit can only "see"
itself.  They are narrowly tuned and sometimes uniquely coded because a
radar set can only deal with timing the arrival of their own return pulses.
If they were wide open to all radar pulses, the radar unit could not
discriminate between its own pulses and another vessels pulses.
Consequently, they would be unable to function.

Comment:
His answer and explanation is correct.
I suspect the original question  stems from  someone reading  stories about
military aircraft systems which  does "see"  other radar systems.
This is a very different animal  consisting of multiple receivers and  very
sophisticated  signal processing  circuits and computers.
Absolutely  no comparison between these military systems and a conventional
marine radar set.

Cheers

Arild

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Arild and Frank, you lost me.  If radars can't "see" other radars, why do
they come equipped with IR (Interference Rejection) controls to minimize the
display of other radars' emissions?

Bob Peterson

-----Original Message-----
From: Arild Jensen
Sent: Tuesday, January 06, 2004 7:33 AM
To: Service@CFX Marine.Com; Trawler-World-List
Subject: RE: Increasing Radar Cross Section, Was: RE: TWL: Re:
Vesselradarreflection

Someone asked the question if another vessel could "see" your radar when it
is transmitting.  The short answer is no, each radar unit can only "see"
itself.
Comment:
His answer and explanation is correct.
I suspect the original question  stems from  someone reading  stories about
military aircraft systems which  does "see"  other radar systems.

Okay, so the definition of "sees" varies among us.  And I wouldn't say that
the arcs of are "no use in locating the other vessel" as they tend to
emanate from the vessel.  Granted it does take some time and patience to
determine their source.

Bob Peterson

-----Original Message-----
From: Peter Bennett [mailto:peterbb@interchange.ubc.ca]
Sent: Tuesday, January 06, 2004 9:00 AM
To: Bob Peterson; trawler-world-list@lists.samurai.com
Subject: Re[2]: Increasing Radar Cross Section, Was: RE: TWL: Re:
Vesselradarreflection

A radar will see signals from other radars operating on the same frequency -
however, the resulting display is random arcs on the screen, and is of no
use in locating the other vessel.