FPQ-6 Tracking and Ranging - Revision history

Paul at 06:58, 25 November 2011

Paul — Fri, 25 Nov 2011 06:58:42 GMT

←Older revision		Revision as of 06:58, 25 November 2011
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-	<BR>	+	==Tracking techniques==
	{{SideMenuQ6TOC}}		{{SideMenuQ6TOC}}
		+	<BR>
	[[Image:Q6-control.jpg\|left\|thumbnail\|400px\|FPQ-6 Control console. Standing in the foreground is Ron Burgess with Geoge Allan in front of him operating the controls, then to the right Len Algate, Q6 Engineer; hidden behind him is Monte Sala, and at the back Mike Marsh. Seated are unknown RCA engineers? : ''Photo – George Allan'']]		[[Image:Q6-control.jpg\|left\|thumbnail\|400px\|FPQ-6 Control console. Standing in the foreground is Ron Burgess with Geoge Allan in front of him operating the controls, then to the right Len Algate, Q6 Engineer; hidden behind him is Monte Sala, and at the back Mike Marsh. Seated are unknown RCA engineers? : ''Photo – George Allan'']]
-	==Tracking techniques==
-	<br><br>
	All tracking systems go through four phases of activity for each track - pre-pass checks, acquisition of spacecraft (or satellite), tracking data output, and post-pass checks – except that for a precision radar, such as the FPQ-6, there are additional refinements. [1]		All tracking systems go through four phases of activity for each track - pre-pass checks, acquisition of spacecraft (or satellite), tracking data output, and post-pass checks – except that for a precision radar, such as the FPQ-6, there are additional refinements. [1]
	<br> <br>		<br> <br>
	===Pre-pass checks===		===Pre-pass checks===
	In addition to the usual slew tests and collimation tower tests of reflector and transponder tests, FPQ-6 recorded the local humidity and pressure entered into the RCA computer to compensate for the refraction coefficient which depends on the atmospheric factors in a complex manner and affects the calculation of range. [2]		In addition to the usual slew tests and collimation tower tests of reflector and transponder tests, FPQ-6 recorded the local humidity and pressure entered into the RCA computer to compensate for the refraction coefficient which depends on the atmospheric factors in a complex manner and affects the calculation of range. [2]
-	<br><br>	+	<br>
	===Acquisition===		===Acquisition===
	Usually, the FPQ-6 antenna was controlled by the data processor from pre-programmed orbital parameters which provided antenna pointing angles and a ranging distance. If no clear radar signal was received, the console technician would modify the pre-programmed tracking path by choosing an antenna angle scan (usually an 8 mil diameter circle) and a range search (usually pm 10,000 yards either side of the predicted range) or through the station ‘acquisition bus’ by slaving to a station antenna which had already locked onto the spacecraft.		Usually, the FPQ-6 antenna was controlled by the data processor from pre-programmed orbital parameters which provided antenna pointing angles and a ranging distance. If no clear radar signal was received, the console technician would modify the pre-programmed tracking path by choosing an antenna angle scan (usually an 8 mil diameter circle) and a range search (usually pm 10,000 yards either side of the predicted range) or through the station ‘acquisition bus’ by slaving to a station antenna which had already locked onto the spacecraft.

Paul at 03:26, 15 August 2011

Paul — Mon, 15 Aug 2011 03:26:24 GMT

←Older revision		Revision as of 03:26, 15 August 2011
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	<BR>		<BR>
	{{SideMenuQ6TOC}}		{{SideMenuQ6TOC}}
-	[[Image:Q6-dinner.jpg\|left\|thumbnail\|220px\|Noted trencher-man and transmitter technician George Allan has his on-duty meal delivered to FPQ-6. Serving him (left to right) are Frank Vinton, Colin Forbes, Nola Meiklejohn, and Geoff Goddard. ''Photo - George Allan'']]	+	[[Image:Q6-control.jpg\|left\|thumbnail\|400px\|FPQ-6 Control console. Standing in the foreground is Ron Burgess with Geoge Allan in front of him operating the controls, then to the right Len Algate, Q6 Engineer; hidden behind him is Monte Sala, and at the back Mike Marsh. Seated are unknown RCA engineers? : ''Photo – George Allan'']]
-	<BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR>	+
	==Tracking techniques==		==Tracking techniques==
		+	<br><br>
	All tracking systems go through four phases of activity for each track - pre-pass checks, acquisition of spacecraft (or satellite), tracking data output, and post-pass checks – except that for a precision radar, such as the FPQ-6, there are additional refinements. [1]		All tracking systems go through four phases of activity for each track - pre-pass checks, acquisition of spacecraft (or satellite), tracking data output, and post-pass checks – except that for a precision radar, such as the FPQ-6, there are additional refinements. [1]
-		+	<br> <br>
	===Pre-pass checks===		===Pre-pass checks===
	In addition to the usual slew tests and collimation tower tests of reflector and transponder tests, FPQ-6 recorded the local humidity and pressure entered into the RCA computer to compensate for the refraction coefficient which depends on the atmospheric factors in a complex manner and affects the calculation of range. [2]		In addition to the usual slew tests and collimation tower tests of reflector and transponder tests, FPQ-6 recorded the local humidity and pressure entered into the RCA computer to compensate for the refraction coefficient which depends on the atmospheric factors in a complex manner and affects the calculation of range. [2]
-		+	<br><br>
	===Acquisition===		===Acquisition===
	Usually, the FPQ-6 antenna was controlled by the data processor from pre-programmed orbital parameters which provided antenna pointing angles and a ranging distance. If no clear radar signal was received, the console technician would modify the pre-programmed tracking path by choosing an antenna angle scan (usually an 8 mil diameter circle) and a range search (usually pm 10,000 yards either side of the predicted range) or through the station ‘acquisition bus’ by slaving to a station antenna which had already locked onto the spacecraft.		Usually, the FPQ-6 antenna was controlled by the data processor from pre-programmed orbital parameters which provided antenna pointing angles and a ranging distance. If no clear radar signal was received, the console technician would modify the pre-programmed tracking path by choosing an antenna angle scan (usually an 8 mil diameter circle) and a range search (usually pm 10,000 yards either side of the predicted range) or through the station ‘acquisition bus’ by slaving to a station antenna which had already locked onto the spacecraft.

Paul: Q6 Tracking Specifics moved to FPQ-6 Tracking and Ranging

Paul — Sun, 04 Mar 2007 02:23:32 GMT

Q6 Tracking Specifics moved to FPQ-6 Tracking and Ranging

←Older revision

Revision as of 02:23, 4 March 2007

Paul: /* Ranging */

Paul — Thu, 08 Feb 2007 00:14:45 GMT

Ranging

←Older revision		Revision as of 00:14, 8 February 2007
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	==Ranging==		==Ranging==
-	The FPQ-6 Digital Ranging Machine [4] used nth-time-around techniques to achieve a maximum unambiguous range of 32,768 nautical miles (60,686 Km) with a precision (accuracy) of ±2 yards (1.8m). The FPS-16 standard radar had only a maximum range of 500 nautical miles with a precision (accuracy) of ±5 yards although later it was modified to 5000 nautical miles as could be the FPQ-6 radar to 256,000 nautical miles.	+	The FPQ-6 Digital Ranging Machine [4], an extended version of the FPS-16 system, used nth-time-around techniques to achieve a maximum unambiguous range of 32,768 nautical miles (60,686 Km) with a precision (accuracy) of ±2 yards (1.8m). The FPS-16 standard radar had only a maximum range of 500 nautical miles with a precision (accuracy) of ±5 yards although later it was modified to 5000 nautical miles as could be the FPQ-6 radar to 256,000 nautical miles.

	The concept of '''precision/accuracy''' needs clarification. Lindsay Sage, an early Chief Engineer of the station, is remembered as saying, ''“You can be very precise and be precisely wrong”''. Precision is the closeness of the individual readings to each other and is nothing to do with how accurately – how close - they are to the true value. Accuracy depends on other factors apart from the structural integrity of the antenna. [5] [[The Science of Tracking#Angle:_The_Requisites_for_Accurate_Tracking\|(read more 'Accuracy' detail)]]		The concept of '''precision/accuracy''' needs clarification. Lindsay Sage, an early Chief Engineer of the station, is remembered as saying, ''“You can be very precise and be precisely wrong”''. Precision is the closeness of the individual readings to each other and is nothing to do with how accurately – how close - they are to the true value. Accuracy depends on other factors apart from the structural integrity of the antenna. [5] [[The Science of Tracking#Angle:_The_Requisites_for_Accurate_Tracking\|(read more 'Accuracy' detail)]]

Paul: /* Angles system */

Paul — Thu, 08 Feb 2007 00:06:41 GMT

Angles system

←Older revision		Revision as of 00:06, 8 February 2007
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	==Angles system==		==Angles system==
	[[Image:Q6-horn.jpg\|right\|thumbnail\|120px\|The Q6 5-horn feed arrangement]]		[[Image:Q6-horn.jpg\|right\|thumbnail\|120px\|The Q6 5-horn feed arrangement]]
-	"The radar employs a 2.8-megawatt peak power (4.8 KW average), broad-banded (5400 to 5900 MC) transmitter with frequency stability of 1 part in 108. The 29-foot diameter antenna dish uses a Cassegrainian feed and has a 51 DB gain with a 0.4-degree beam width. Its monopulse, 5-horn feed system permits the reference and error antenna patterns to have their gains independently established as well as the slope of the error patterns optimized while supplying target return signals to the receiving system with a minimum of feed insertion loss." [6]	+	"The radar employs a 2.8-megawatt peak power (4.8 KW average), broad-banded (5400 to 5900 MC) transmitter with frequency stability of 1 part in 108. The 29-foot diameter antenna dish uses a Cassegrainian feed and has a 51 DB gain with a 0.4-degree beam width. Its monopulse, 5-horn feed system permits the reference and error antenna patterns to have their gains independently established as well as the slope of the error patterns optimized while supplying target return signals to the receiving system with a minimum of feed insertion loss." [6] [[The Science of Tracking#Angle:_Relative–phase_measurement\|(read more 'Angle' detail)]]

-	[[The Science of Tracking#Angle:_Relative–phase_measurement\|(read more 'Angle' detail)]]	+	"This design has advantages over conventional monopulse feeds and reduces the possibility of side lobe lock-on. The three-channel signal outputs of the antenna feed system [Az., El., and Ref.] are supplied directly to the receiving system without undergoing any additional, loss-inducing, signal manipulation. The three-channel monopulse receiving system has its bandwidths optimized for the specified pulse widths of 0.5, 0.75, 1.0, and 2.4 microseconds, and the receiver noise figure of 7.5 DB has been improved to 3.5 DB through the addition of closed-cycle, parametric RF amplifiers." [6]
-		+
-	This design has advantages over conventional monopulse feeds and reduces the possibility of side lobe lock-on. The three-channel signal outputs of the antenna feed system [Az., El., and Ref.] are supplied directly to the receiving system without undergoing any additional, loss-inducing, signal manipulation. The three-channel monopulse receiving system has its bandwidths optimized for the specified pulse widths of 0.5, 0.75, 1.0, and 2.4 microseconds, and the receiver noise figure of 7.5 DB has been improved to 3.5 DB through the addition of closed-cycle, parametric RF amplifiers." [6]	+

	Angle pointing accuracy is 0.1 mil (0.005625°)		Angle pointing accuracy is 0.1 mil (0.005625°)

Paul at 00:04, 8 February 2007

Paul — Thu, 08 Feb 2007 00:04:35 GMT

←Older revision		Revision as of 00:04, 8 February 2007
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	==Angles system==		==Angles system==
-	[[Image:Q6-horn.jpg\|right\|thumbnail\|120px\|The FPQ-6 horn arrangement]]	+	[[Image:Q6-horn.jpg\|right\|thumbnail\|120px\|The Q6 5-horn feed arrangement]]
-	"The radar employs a 2.8-megawatt peak power (4.8 KW average), broad-banded (5400 to 5900 MC) transmitter with frequency stability of 1 part in 108. The 29-foot diameter antenna dish uses a Cassegrainian feed and has a 51 DB gain with a 0.4-degree beam width. Its monopulse, 5-horn feed system permits the reference and error antenna patterns to have their gains independently established as well as the slope of the error patterns optimized while supplying target return signals to the receiving system with a minimum of feed insertion loss.<BR>	+	"The radar employs a 2.8-megawatt peak power (4.8 KW average), broad-banded (5400 to 5900 MC) transmitter with frequency stability of 1 part in 108. The 29-foot diameter antenna dish uses a Cassegrainian feed and has a 51 DB gain with a 0.4-degree beam width. Its monopulse, 5-horn feed system permits the reference and error antenna patterns to have their gains independently established as well as the slope of the error patterns optimized while supplying target return signals to the receiving system with a minimum of feed insertion loss." [6]
-	[[The Science of Tracking#Angle:_Relative–phase_measurement\|(read more 'Angle' detail)]]<BR>	+
		+	[[The Science of Tracking#Angle:_Relative–phase_measurement\|(read more 'Angle' detail)]]
		+
	This design has advantages over conventional monopulse feeds and reduces the possibility of side lobe lock-on. The three-channel signal outputs of the antenna feed system [Az., El., and Ref.] are supplied directly to the receiving system without undergoing any additional, loss-inducing, signal manipulation. The three-channel monopulse receiving system has its bandwidths optimized for the specified pulse widths of 0.5, 0.75, 1.0, and 2.4 microseconds, and the receiver noise figure of 7.5 DB has been improved to 3.5 DB through the addition of closed-cycle, parametric RF amplifiers." [6]		This design has advantages over conventional monopulse feeds and reduces the possibility of side lobe lock-on. The three-channel signal outputs of the antenna feed system [Az., El., and Ref.] are supplied directly to the receiving system without undergoing any additional, loss-inducing, signal manipulation. The three-channel monopulse receiving system has its bandwidths optimized for the specified pulse widths of 0.5, 0.75, 1.0, and 2.4 microseconds, and the receiver noise figure of 7.5 DB has been improved to 3.5 DB through the addition of closed-cycle, parametric RF amplifiers." [6]

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	Bob Hocking recalls: ''“On at least two occasions the small dish became detached. I think once it hung from its coaxial cable. The other time it was found on the ground. No one noticed it was missing. During servo bandwidth tests it took a fair hammering. I attached a label to the function generator amplitude control marked ‘Side-lobe Dish Jettiron’. Later Dave Gardiner put a patch in the Real Time Program’ and through a bit of my hardware [it[ killed the servo drive and applied the brakes, This was known as the anti-Kloppenburg device.”'' [8] An application for this engineering change was never made.		Bob Hocking recalls: ''“On at least two occasions the small dish became detached. I think once it hung from its coaxial cable. The other time it was found on the ground. No one noticed it was missing. During servo bandwidth tests it took a fair hammering. I attached a label to the function generator amplitude control marked ‘Side-lobe Dish Jettiron’. Later Dave Gardiner put a patch in the Real Time Program’ and through a bit of my hardware [it[ killed the servo drive and applied the brakes, This was known as the anti-Kloppenburg device.”'' [8] An application for this engineering change was never made.
-
-	[[#top]]<BR>
-
-	==Computer assistance==
-
-

	[[#top]]<BR>		[[#top]]<BR>

Paul at 05:14, 7 February 2007

Paul — Wed, 07 Feb 2007 05:14:58 GMT

←Older revision		Revision as of 05:14, 7 February 2007
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	{{SideMenuQ6TOC}}		{{SideMenuQ6TOC}}
	[[Image:Q6-dinner.jpg\|left\|thumbnail\|220px\|Noted trencher-man and transmitter technician George Allan has his on-duty meal delivered to FPQ-6. Serving him (left to right) are Frank Vinton, Colin Forbes, Nola Meiklejohn, and Geoff Goddard. ''Photo - George Allan'']]		[[Image:Q6-dinner.jpg\|left\|thumbnail\|220px\|Noted trencher-man and transmitter technician George Allan has his on-duty meal delivered to FPQ-6. Serving him (left to right) are Frank Vinton, Colin Forbes, Nola Meiklejohn, and Geoff Goddard. ''Photo - George Allan'']]

Paul at 05:13, 7 February 2007

Paul — Wed, 07 Feb 2007 05:13:56 GMT

←Older revision		Revision as of 05:13, 7 February 2007
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	{{SideMenuQ6TOC}}		{{SideMenuQ6TOC}}
	[[Image:Q6-dinner.jpg\|left\|thumbnail\|220px\|Noted trencher-man and transmitter technician George Allan has his on-duty meal delivered to FPQ-6. Serving him (left to right) are Frank Vinton, Colin Forbes, Nola Meiklejohn, and Geoff Goddard. ''Photo - George Allan'']]		[[Image:Q6-dinner.jpg\|left\|thumbnail\|220px\|Noted trencher-man and transmitter technician George Allan has his on-duty meal delivered to FPQ-6. Serving him (left to right) are Frank Vinton, Colin Forbes, Nola Meiklejohn, and Geoff Goddard. ''Photo - George Allan'']]
-	<BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR>	+	<BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR>
	==Tracking techniques==		==Tracking techniques==
	All tracking systems go through four phases of activity for each track - pre-pass checks, acquisition of spacecraft (or satellite), tracking data output, and post-pass checks – except that for a precision radar, such as the FPQ-6, there are additional refinements. [1]		All tracking systems go through four phases of activity for each track - pre-pass checks, acquisition of spacecraft (or satellite), tracking data output, and post-pass checks – except that for a precision radar, such as the FPQ-6, there are additional refinements. [1]

Paul at 05:13, 7 February 2007

Paul — Wed, 07 Feb 2007 05:13:14 GMT

←Older revision		Revision as of 05:13, 7 February 2007
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-	<BR>
	{{SideMenuQ6TOC}}		{{SideMenuQ6TOC}}
	[[Image:Q6-dinner.jpg\|left\|thumbnail\|220px\|Noted trencher-man and transmitter technician George Allan has his on-duty meal delivered to FPQ-6. Serving him (left to right) are Frank Vinton, Colin Forbes, Nola Meiklejohn, and Geoff Goddard. ''Photo - George Allan'']]		[[Image:Q6-dinner.jpg\|left\|thumbnail\|220px\|Noted trencher-man and transmitter technician George Allan has his on-duty meal delivered to FPQ-6. Serving him (left to right) are Frank Vinton, Colin Forbes, Nola Meiklejohn, and Geoff Goddard. ''Photo - George Allan'']]

Paul at 05:12, 7 February 2007

Paul — Wed, 07 Feb 2007 05:12:36 GMT

←Older revision		Revision as of 05:12, 7 February 2007
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	{{SideMenuQ6TOC}}		{{SideMenuQ6TOC}}
	[[Image:Q6-dinner.jpg\|left\|thumbnail\|220px\|Noted trencher-man and transmitter technician George Allan has his on-duty meal delivered to FPQ-6. Serving him (left to right) are Frank Vinton, Colin Forbes, Nola Meiklejohn, and Geoff Goddard. ''Photo - George Allan'']]		[[Image:Q6-dinner.jpg\|left\|thumbnail\|220px\|Noted trencher-man and transmitter technician George Allan has his on-duty meal delivered to FPQ-6. Serving him (left to right) are Frank Vinton, Colin Forbes, Nola Meiklejohn, and Geoff Goddard. ''Photo - George Allan'']]
-	<BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR>	+	<BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR>
	==Tracking techniques==		==Tracking techniques==
	All tracking systems go through four phases of activity for each track - pre-pass checks, acquisition of spacecraft (or satellite), tracking data output, and post-pass checks – except that for a precision radar, such as the FPQ-6, there are additional refinements. [1]		All tracking systems go through four phases of activity for each track - pre-pass checks, acquisition of spacecraft (or satellite), tracking data output, and post-pass checks – except that for a precision radar, such as the FPQ-6, there are additional refinements. [1]