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Re: Radar ranging and relativity

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On 3/18/2023 11:31 PM, Volney wrote:
> On 3/17/2023 11:12 PM, Richard Hertz wrote:
>> On Saturday, March 18, 2023 at 12:01:26 AM UTC-3, Sylvia Else wrote:
>>> On 18-Mar-23 3:45 am, Richard Hertz wrote:
>>>> Why the popularized equation for radar ranging is:
>>>>
>>>> R = 1/2 t c₀
>>>>
>>>> https://www.radartutorial.eu/01.basics/Distance-determination.en.html
>>> For a target, moving or otherwise, it gives the distance to the target
>>> at the point where the radar signal was reflected, which happens after
>>> half of the total transit time. The velocity of the target is 
>>> irrelevant.
>>>
>>> Sylvia.
>>
>> This is the basic theory for radar ranging, taught to kids in high 
>> school.
>>
>> I wrote the OP in order to show the DISINFORMATION that plagues the 
>> web, being in this case from a "serious" site.
>>
>> Since the 60s, radar ranging is complemented with Doppler measurement, 
>> in a single frequency swept pulse, and even
>> better techniques.
>>
>> Since the 90s, phased array radars are used along with computes, to 
>> acquire targets in a 3D space with resolutions of meters.
>>
> The more you post on electronics, the more I think you are not an EE, 
> but you know all the buzzwords.



To the real point, what does any of that matter? Posts are right or they
are wrong/mistaken. There's still an awful lot of "angels dancing on the
head of a pin" style discussion here. Personally I find it useless and
boring. The conditions that created uncle al are unchanged. Too bad.

With very little effort these could be worthwhile newsgroups as they
once were.


> It doesn't matter about all the phased array, Doppler shifted, 
> spread-spectrum, jamproof AM/FM discombobulated 4D space color display 
> radar that can tell what the pilot of an enemy fighter had for breakfast 
> that morning, deep down underneath it all, the radar sends out a signal 
> and some of it gets reflected by a target and returned to the sending 
> unit with a delay. Part of the information available is the range R=1/2 
> ct where t is the delay of a certain portion of the signal returned to 
> the radar unit.
> 
> The fact there's no longer a turning dish going "ping" and an 
> oscilloscope type display with green dots showing the targets is 
> irrelevant. (although I see the Russians still use equipment with the 
> turning antennas)

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Radar ranging and relativity Richard Hertz <hertz778@gmail.com> - 2023-03-17 09:45 -0700
  Re: Radar ranging and relativity Richard Hertz <hertz778@gmail.com> - 2023-03-17 10:21 -0700
  Re: Radar ranging and relativity "Dono." <eggy20011951@gmail.com> - 2023-03-17 19:03 -0700
    Re: Radar ranging and relativity Richard Hertz <hertz778@gmail.com> - 2023-03-17 19:51 -0700
      Cretin Richard Hertz at work "Dono." <eggy20011951@gmail.com> - 2023-03-17 21:17 -0700
  Re: Radar ranging and relativity "Dono." <eggy20011951@gmail.com> - 2023-03-17 19:48 -0700
    Re: Radar ranging and relativity whodat <whodaat@void.nowgre.com> - 2023-03-17 22:02 -0500
  Re: Radar ranging and relativity Sylvia Else <sylvia@email.invalid> - 2023-03-18 14:01 +1100
    Re: Radar ranging and relativity Richard Hertz <hertz778@gmail.com> - 2023-03-17 20:12 -0700
      Re: Radar ranging and relativity whodat <whodaat@void.nowgre.com> - 2023-03-17 22:29 -0500
        Re: Radar ranging and relativity Richard Hertz <hertz778@gmail.com> - 2023-03-18 05:44 -0700
      Re: Radar ranging and relativity Sylvia Else <sylvia@email.invalid> - 2023-03-18 15:08 +1100
      Re: Radar ranging and relativity Volney <volney@invalid.invalid> - 2023-03-19 00:31 -0400
        Re: Radar ranging and relativity whodat <whodaat@void.nowgre.com> - 2023-03-18 23:49 -0500
        Re: Radar ranging and relativity Maciej Wozniak <maluwozniak@gmail.com> - 2023-03-19 00:20 -0700
  Re: Radar ranging and relativity "mitchr...@gmail.com" <mitchrae3323@gmail.com> - 2023-03-18 12:49 -0700
    Re: Radar ranging and relativity Richard Hertz <hertz778@gmail.com> - 2023-03-18 13:33 -0700
      Re: Radar ranging and relativity "Dono." <eggy20011951@gmail.com> - 2023-03-18 16:14 -0700
  Re: Radar ranging and relativity "Paul B. Andersen" <paul.b.andersen@paulba.no> - 2023-03-21 22:24 +0100

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