When a RADAR is being operated on the 48 mile range setting, what is the most appropriate pulse width (PW) and pulse repetition rate (pps)?

1.0 μs PW and 500 pps.

The question is, given the distance, how many pulses can be sent so that no more than one pulse returns before the next one.

Divide 48 miles by the speed of light of 186,000 miles per second, resulting in 0.00025806451 of a second. Then, the double, to include the returning echo, it comes to 0.0005162903 of a second. For 1 second, we divide 1/0.0005162903, resulting in 1937 pulses maximum. The only choice that has less is the one of 500 PPS.

The 1.0 μs is the Pulse Width, and the 500 is the pulse repetition rate.

This is a range calculation, with the range given. The maximum range has been achieved when the echo of the received transmission signal is measured at the minimum signal strength which can be detected. If the target moves, then we must calculate the "range-rate."

How many pps (pulses per second) affects the radar's range, given that the target is stationary. The radar range should be greater than about half of the pulse time length.

Please see Tutorials Points site for the applicable formula here, listed in the article Radar Systems - Range Equation

Also, see ECE UAH EDU site for the pdf article 2.0 RADAR RANGE EQUATION

And, see Richarddsonrfpd site for the pdf document Radar Tutorial

For the excellent well-illustrated overview of signal processing, please see the pdf PowerPoint presentation on the Introduction to Radar Signal Processing

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When a RADAR is being operated on the 6 mile range setting what is the most appropriate pulse width and pulse repetition rate?

0.25 μs PW and 1,000 pps.

PRR is the pulse repetition rate. PW is the pulse width. PPS is the pulse per second.

[STUDY NOTE]: Keep in mind the PW and PPS (PRR) relationship: short distances = less PW & more PPS; longer distances = more PW & less PPS.
[/END STUDY NOTE]

Original Tip The 0.25 μs microseconds is the Pulse Width, and the 1,000 is the pulse repetition rate.

There are 1,000,000 μs microseconds in one second. If we take the ratio of 6 miles divided by 186,000 miles per 1,000,000 μs microseconds, and multiply by 1,000,000 μs microseconds, we get 32.258 μs microseconds.

Then, we have to double it to get the time of the round trip, or 64.516 μs microseconds. Therefore, in 1,000,000 μs microseconds, or 1 second, we have 15500 PPS, pulses per 1 second maximum.

This, would suggest the answer of the pulse width of 2 μs microseconds with the 3,000 pps. Since the distance is only 6 miles, such a wide signal would not be as appropriate as the .25 μs microseconds per 1,000 pps.

This is a range calculation, with the range given. The maximum range has been achieved when the echo of the received transmission signal is measured at the minimum signal strength which can be detected. If the target moves, then we must calculate the "range-rate."

How many pps (pulses per second) affects the radar's range, given that the target is stationary. The radar range should be greater than about half of the pulse time length.

Please see Tutorials Points site for the applicable formula here, listed on the article Radar Systems - Range Equation

Also, see ECE UAH EDU site for the pdf article 2.0 RADAR RANGE EQUATION

And, see Richarddsonrfpd site for the pdf document Radar Tutorial

For the excellent well-illustrated overview of signal processing, please see the pdf PowerPoint presentation on the Introduction to Radar Signal Processing

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We are looking at a target 25 miles away. When a RADAR is being operated on the 25 mile range setting what is the most appropriate pulse width and pulse repetition rate?

1.0 μs PW and 500 pps.

The 1.0 μs is the Pulse Width, and the 500 is the pulse repetition rate.

PRR is the pulse repetition rate. PW is the pulse width. PPS is the pulse per second.

This is a range calculation, with the range given. The maximum range has been achieved when the echo of the received transmission signal is measured at the minimum signal strength which can be detected. If the target moves, then we must calculate the "range-rate."

How many PPS (pulses per second) affects the radar's range, given that the target is stationary. The radar range should be greater than about half of the pulse time length.

The rule is that the PPS rate has to be longer than it takes the signal to hit the target and return, so that the radar can read the returning signal clearly.

The longer the period, the greater the pulse repetition rate can be. The shorter the period, the smaller the pulse repetition rate can be. This is an inverse relationship between the PRR and the period.

When the target is 25 miles away, first we have to determine how long it takes the signal at the speed of light to get there, which is 25 miles / 186,000 miles/second, or 0.0001344086. Then to return, for the total forth/back is twice as long or 0.00026881732 of a second.

To determine the PRR, an inverse of period, we divide the 1 second by 0.00026881732, to get about 3719 pulses per second PPS. No more pulses can be generated within 1 second.

Because a target is 25 miles away, the largest PW pulse width will bring a clearer signal reading, as larger PW sends more energy. Thus, the 1 μs is the largest PW among the answers. All PPS answers are well below the 3719 pulses per second PPS limit.

Please see Tutorials Points site for the applicable formula here, listed in the article Radar Systems - Range Equation

Also, see ECE UAH EDU site for the pdf article 2.0 RADAR RANGE EQUATION

And, see Richarddsonrfpd site for the pdf document Radar Tutorial

For the excellent well-illustrated overview of signal processing, please see the pdf PowerPoint presentation on the Introduction to Radar Signal Processing

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What pulse width and repetition rate should you use at long ranges?

Wide pulse width and slow repetition rate.

This is a range calculation, with the range given. The maximum range has been achieved when the echo of the received transmission signal is measured at the minimum signal strength PW which can be detected. If the target moves, then we must calculate the "range-rate."

How many PPS (pulses per second) affects the radar's range, given that the target is stationary. The radar range should be greater than about half of the pulse time length.

For long ranges, where distance is a factor, the best choice has the maximum PW pulse width which is the measure of the energy sent, at the cost of lower PRR.

Please see Tutorials Points site for the applicable formula here, listed on the article Radar Systems - Range Equation

Also, see ECE UAH EDU site for the pdf article 2.0 RADAR RANGE EQUATION

And, see Richarddsonrfpd site for the pdf document Radar Tutorial

For the excellent well-illustrated overview of signal processing, please see the pdf PowerPoint presentation on the Introduction to Radar Signal Processing

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What pulse width and repetition rate should you use at short ranges?

Narrow pulse width and fast repetition rates.

This is a range calculation, with the range given. The maximum range has been achieved when the echo of the received transmission signal is measured at the minimum signal strength which can be detected. If the target moves, then we must calculate the "range-rate."

How many pps (pulses per second) affects the radar's range, given that the target is stationary. The radar range should be greater than about half of the pulse time length.

Please see Tutorials Points site for the applicable formula here, listed on the article Radar Systems - Range Equation

Also, see ECE UAH EDU site for the pdf article 2.0 RADAR RANGE EQUATION

And, see Richarddsonrfpd site for the pdf document Radar Tutorial

For the excellent well-illustrated overview of signal processing, please see the pdf PowerPoint presentation on the Introduction to Radar Signal Processing

Last edited by markadlerdallas. Register to edit

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When a RADAR is being operated on the 1.5 mile range setting, what is the most appropriate pulse width and pulse repetition rate?

0.05 μs PW and 2,000 pps

From wp2ahg:

1.5 miles is really close. You need the shortest pulse width in the list (0.05 microseconds).

The 0.05 μs is the. PW Pulse Width, and the 2,000 is the pulse repetition rate, PRR

Since the range is very close, lower PW will work well, thus allowing the signal selection to maximize the PRR.

This is a range calculation, with the range given. The maximum range has been achieved when the echo of the received transmission signal is measured at the minimum signal strength which can be detected. If the target moves, then we must calculate the "range-rate."

How many pps (pulses per second) affects the radar's range, given that the target is stationary. The radar range should be greater than about half of the pulse time length.

Please see Tutorials Points site for the applicable formula here, listed on the article Radar Systems - Range Equation

Also, see ECE UAH EDU site for the pdf article 2.0 RADAR RANGE EQUATION

And, see Richarddsonrfpd site for the pdf document Radar Tutorial

For the excellent well-illustrated overview of signal processing, please see the pdf PowerPoint presentation on the Introduction to Radar Signal Processing

Last edited by markadlerdallas. Register to edit

Tags: none