US3897917A

US3897917A - Weapon delivery system

Info

Publication number: US3897917A
Application number: US291106A
Authority: US
Inventors: Robert Henry Johnson
Original assignee: Motorola Inc
Current assignee: Motorola Solutions Inc
Priority date: 1972-09-21
Filing date: 1972-09-21
Publication date: 1975-08-05
Anticipated expiration: 1992-08-05
Also published as: GB1411028A; IT991986B; DE2347460A1; JPS4970398A; GB1411027A; IL43100A0

Abstract

Apparatus and system for guiding a bomb, or the like, to a radiating target is disclosed wherein a series of sensors on the bomb are sensed sequentially and the signals processed in a single circuit, and when signals of threshold or greater values are received they are sequentially sampled and stored. Subsequently the stored signals are summed and used to direct the bomb in azimuth and elevation. Improved means for obtaining the signal from its surrounding noise and improved means for obtaining target resolution of about 20 feet or less are also disclosed.

Description

United States Patent Johnson Aug. 5, 1975 l WEAPON DELIVERY SYSTEM Primary ExuminerBenjamin A. Borchelt [75] Inventor: Robert Henry Johnson, Scottsdale, T H, Vl/ebb V AriL Attorney. Agent, or Firm-Sang Ki Lee; Vincent J.

Rauner [73] Assignee: Motorola, Inc., Chicago, Ill.

[22] Filed: Sept. 21, 1972 ABSTRACT [2 l] Appl. No; 291,106 Apparatus and system forguiding a bomb, or the like, to a radiating target IS disclosed wherein a series of sensors on the bomb are sensed sequentially and the [52] Cl 244/516; 244/319 signals processed in a single circuit, and when signals [5 l] 'l CL 3 7/104 Fllg 7/00; F418 9/00 of threshold or greater values are received they are se- [58] Field of Search [OZ/70.2; 244/3.l9, 3 16; quemiany Sampled and Stol-ECL Subsequent, the 89/4] ME stored signals are summed and used to direct the bomb in azimuth and elevation. [56] References Cited Improved means for obtaining the signal from its UNITED STATES PATENTS surrounding noise and improved means for obtaining 3.72U.l3l 3/19 3 Fr h ck 39/41 ME target resolution of about 20 feet or less are also disclosed.

15 Claims, 7 Drawing Figures 33 75 52 22 28 at as 45/ 47 52 56 6| g g i r sw T0 AZIMUTH 34 76 M CONTROL 2: 29 x 18 53 57 62 se SW 35 66 7| 72 35 77 84 l 25 24 39 419 54 58 e9 SW 79 g TO ELEVATION f 85 53 CONTROL 9| SEQUENCER WEAPON DELIVERY SYSTEM BACKGROUND OF THE INVENTION This invention relates to systems and apparatus for guiding missiles, bombs, or the like, to surface targets, more particularly to such systems and apparatus wherein the target is radiating an X band or higher frequency signal and it is an object of the invention to provide improved systems and apparatus of this nature,

Radiation beam systems for delivering missiles or similar weapons to surface targets are known to the art. These systems and apparatus have been bulky, expensive and complicated, and it is an object of the invention to provide a missile guiding system of the nature indicated which overcomes these objections of the prior art and is on the contrary simple, inexpensive, light in weight, small in size and effective.

It is a further object of the invention to provide a missile guiding system of the nature indicated which is not affected by clutter and other spurious radiated signals.

SUMMARY OF THE INVENTION In carrying out the invention in one form there is provided a control system for guiding a missile in azimuth and elevation toward a radiating target comprising a series of sensors adapted to be disposed on such missile for receiving such radiation and being adapted for determining azimuthal and elevational information; a processing circuit for the signals from said sensors; a first series of fast acting switches one each of which is connected between one each of said sensors and said processing circuit; each one of said first series of switches including meanss for setting the on and off condition of the respective switch; a series of sample and hold means one each for each of said sensors connected to receive the signals from the processing circuit; each one of said series of sample and hold means including means for setting the on and off condition of the re spective sample and hold means; an azimuthal signal comparator and an elevational signal comparator; a second series of fast acting switches one each of which is connected to one each of said sample and hold means, respectively, azimuthally related ones of said second series of fast acting switches being connected to said azimuthal signal comparator and elevationally related ones of said second series of fast acting switches being connected to said elevational signal comparator; each one of said second series of fast acting switches including means for setting the on and off condition of the respective switch; sequencing means connected to the setting means of said first series of fast acting switches and to the setting means of said sample and hold means for simultaneously and sequentially turning on and off related ones of said first series of fast acting switches and said sample and hold means; said sequencing means further being connected to the setting means of said second series of fast acting switches for sequentially initiating comparison in said azimuth signal comparator of said azimuth signals and in said elevation signal comparator of said elevation signals; means for supplying the compared signal of said azimuth signal comparator to azimuth control means; and means for supplying the compared signal of said elevation signal comparator to elevation control means.

In carrying out the invention according to another form there is provided a control system for guiding a missile in azimuth and elevation toward a radiating target comprising; a series of sensors adapted to be disposed on such missile for simultaneous exposure to such radiation and being adapted for determining azimuthal and elevational signals; means for sequentially sampling in continuous cycles the signals on said sensors and holding the sampled data until all sensors have been sampled in each cycle; means effective after said sampling sequence in each cycle for comparing the held azimuthal data and the held elevational data; and means for transmitting said compared azimuthal data to azimuth utilization means and said elevational data to elevation utilization means.

According to a still further form the control system of the invention includes means for improving the signal to raise the ratio of the signals on said sensors; means for detecting a threshold value of said signals and preventing sampling and holding of such signals unless at least equal to said threshold value, and means for discriminating against extraneous pulses.

Further objects and advantages will become apparent as the description proceeds.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic representation of a bomb being delivered to a target in accordance with the invention',

FIG. 2 is a block diagram illustrating a control system according to the invention;

FIG. 3 is a series of pulse diagrams useful in understanding the operation of the invention;

FIG. 4 is diagrammatic representation of one component of the inventive apparatus;

FIG. 5 is a series of wave shapes illustrating direct and reflected pulses on a different scale;

FIG. 6 is a diagrammatic representation of another component of the inventive apparatus; and

FIG. 7 is a timing diagram useful in understanding the operation of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, the invention is shown as comprising a control circuit 10 (FIG. 2) to be included on a bomb, or the like, 11 illustrated in FIG. 1 as being directed toward a bridge 12, the bomb being guided by the radiation beam 13 emanating from a transmitter 14 secreted on the bridge floor.

While a falling bomb has been shown, this is exem plary, and it will be understood that the invention has application to bombs, missiles, and the like generally. It has equal application to any moving object, or equipment. It will also be understood, throughout this specification, that radiation includes direct radiation from one, or more, generating sources, reflected radiation of such sources from nearby objects and combined radia tion pulses, or beams.

The radar (radiation) beam 13 may be exemplified by a pulse 15 which is intended to be received by, and to actuate, the mechanism aboard, the bomb II for guiding it to the designated spot.

In addition to the direct radiation path 13, there may be any number of alternate radiation paths resulting from reflections of the signals from other objects or surfaces. The reflected paths are exemplified by the beam 16 which includes a path portion I7 extending from the transmitter to the nearest reflecting surface, for example, as the river or other stream 18. The reflected path I6 is longer by the distance 17 and thus the pulse 19 exemplifying the beam 16 is shown behind the pulse 15, signifying a delay in time.

It is one of the objects of the invention to provide a control circuit which enables the bomb control mechanism to distinguish between the first, or direct. pulse 15 and a second, or reflected. pulse 19 when the leading edges of these pulses may be no farther apart than about 20 feet. That is to say, the bomb mechanism is intended to resolve errors or distinguish between points no farther than about twenty feet, but possibly less. Bearing in mind that radiation travels one foot per nanosecond (n.s.), this means that the circuitry aboard the bomb must be able to function and develop the necessary control signals based upon a signal time of no greater than 20 nanoseconds, or less. Accordingly, the circuit components must be very fast.

Moreover, the circuitry in total must be small so that it can be placed in a small compartment within the bomb and not detract from the explosive carrying capa bility thereof. It likewise must not require large amounts of power to function for essentially the same reason. In addition, the utilization of such control circuitry aboard large numbers of bombs, or the like, requires that the overall cost of the control circuit be very small. The circuitry must be functional under all kinds of weather conditions, whether it be rain, dust, clouds, snow, darkness, or other obscuring conditions. Having the transmitter 14 generate microwaves around the X band, for example, of the orrder of gigahertz (GHZ) or higher serves the purposes indicated.

The transmitter 14 may be of any well-known form for generating frequencies of the nature indicated and should be small so as to be readily concealable on a bridge, bunker, or other structure, which is intended to be destroyed. The transmitter may be disposed on the target in any known fashion such for example as being left there by withdrawing troups, being deposited secretively by an agent, or, for that matter, being delivered to the structure by parachute or otherwise.

In any vicinity there may, of course, be more than one target, each of which has a transmitter disposed thereon, which is radiating a signal of the same fre quency as the one which is intended for destruction by a particular bomb. The bomb after being directed at a particular target is intended to home in upon that target by receiving the radiated signal therefrom while excluding, or discriminating against, the signals being radiated by other targets in the vicinity. The ability to re solve signals differing in time by about twenty nanoseconds or less, as indicated, is adequate for this purpose.

Referring more specifically to FIG. 2, four sensors such as

wide beam antennas

21, 22, 23 and 24 may be quadrantally mounted about the nose of the bomb as shown in FIG. I. Antennas 2] and 23 may, for example, control the bomb in elevation while the antennas 22 and 24 control the bomb in azimuth. More or less antennas, or other sensors, may be used to suit the particular circumstances. The elevational control is indicated by the reference character 25 and the azimuthal control is indicated by the reference character 26 in FIG. 2.

The

sensors

21, 22, 23, and 24 are connected, respectively, through conductors 27, 28, 29 and 31 to the in-terminals of switches 32, 33, 34 and 35 respectively. The exit-terminals of switches 32, 33, 34 and 35 are connected, respectively, through conductors 36, 37, 38

and 39 to a conductor 41 which in turn is connected through conductor 42 to the input side of a processing circuit 43.

The output side of processing circuit 43 is connected through conductor 44 to a conductor 45 and thus through conductors 46, 47, 48 and 49 to the interminals of sample and hold circuits 5]. 52, 53. 54 respectively. The exit-terminals of sample and hold circuits 51, 52, 53, 54 are connected, respectively, through conductors 55, 56, 57 and 58 to switches 59, 6], 62 and 63, respectively. The exit-terminals of switches 59 and 62 are connected, respectively, by means of conductors 64 and 65 to the in-terminals of a comparator circuit 66. Similarly the exit-terminals of switches 61 and 63 are connected, respectively, through conductors 67 and 68 to the in-terminals of a comparator circuit 69. The exit-terminal of comparator circuit 66 is connected through conductor 71 to the interminal of an integrating circuit 72 and thus to the elevation control. Similarly the exit-terminal of comparator circuit 69 is connected through conductor 73 to the in-terminal of an integrating circuit 74 and thus to the azimuth control.

The switches 32-35 may be of any well-known form suitable for the purpose but in a preferred form of the invention are well known, fast-acting solid state devices. The on and off conditions thereof are controlled by appropriate voltage pulses, or levels, appearing on conductors 75, 76, 77, and 78, respectively, and thus from conductor 79 connected to sequencer 81 from which the control signals are supplied.

The sample and hold circuits 51-54 to be more particularly described are controlled by appropriate signals appearing on their control terminals through conductors 82, 83, 84 and 85, respectively, connected to a conductor 86 which is in turn connected to sequencer 81 which supplies the appropriate control voltages as will be described.

The switches 5963 inclusive, also, may be of any suitable type appropriate to the purpose but according to a preferred form of the invention are well-known, fast-acting solid state devices. The on and off conditions thereof (activations and deactivations) are controlled by appropriate voltage pulses, or levels, appearing on conductors 87, 88, 89 and 91. Conductors 87, 88, 89 and 9] are connected to a conductor 92 which, in turn, is connected to the sequencer 81 which supplies the control signals as will be more particularly described.

In operation, the sequencer serves to activate the appropriate switches and the sample and hold circuits in the desired sequence so that each incoming signal is processed in the processing circuit 43 in its turn. Thus only one processing circuit 43 is needed and problems of balancing such circuits as between several of them (as in other systems) are eliminated. Switch 32 is activated, or in the on condition, at the same time that sample and hold 51 and switch 59 are activated, switch 33 is activated at the same time that sample and hold 52 and switch 61 are activated, switch 34 is activated at the same time that sample and hold 53 and switch 62 are activated, and switch 35 is activated at the same time that sample and hold 54 and switch 63 are activated.

The processing circuit 43, as shown, comprises a mixer 93, an amplifier 94, a compression filter, or the like, 95, and an amplifier 96 connected as shown by

conductors

97, 98, and 99 between the input conductors 42 and 44. The output signal of amplifier 96 at conductor 44 is also connected through a conductor N11 to a threshold detector 102 and thus through a conductor M3 to control the sequencer 81. In the processing circuit shown. the mixer serves the usual function of heterodyning the incoming frequency with a locally generated signal (not shown) to develop a signal of intermediate frequency which is processed through the circuitry.

The amplifiers of well-known type serve their usual function and the compression filter 95 is one form of device which may be used, according to the invention. to separate the intelligence. or desired signal. from the surrounding noise in which it may appear. A compression filter, such as acoustic surface wave devices, biphase coded devices utilizing shift registers, or other devices may be used for signal extraction.

Acoustic surface wave devices, as will be more particularly described, may be utilized for producing a delay in the received signal for any purpose desired.

The sequencer 81 activates (turns on) the switches 32, 33, 34 and 35 in sequence, each being on for 0.001 second, for example, but as previously indicated the signals from sensors, or

antennas

21 and 23 ultimately are compared in comparator 66 for controlling the elevation and the signals from sensors, or antennas 22 and 24, and ultimately are compared in comparator 69 for controlling the azimuth. The sequence 81 may be of any wellknown form which will develop voltage pulses, or levels, of the desired value and at the proper time, and in the proper sequence.

The signal generated by transmitter 14 may be in the form of bursts of pulses whose envelope is shown by the square pulse 104 of FIG. 3. The burst typically may last for 2.5 microseconds, or less, and have a peak power of about one watt or more. The radar, or radiated signal, need not be of fixed frequency, but according to one form of the invention may vary about 250 mHZ or less during the 2.5 microsecond, for example, interval as shown by the triangular outline 105, of FIG. 3, F be ing, for example, 9,750 megacycles and F being [0,000 megacycles. When such a pulse is received by the compression filter 95 the 2.5 microsecond interval is compressed into. for example, 0.1 microseconds whereby the peak power is amplified from 1 watt to 25 watts, on an unattenuated basis, as shown by the outline 106 of FIG. 3. The power amplification ratio of 25 is sufficient to cause the desired or

intelligence signal

104, 106 to emerge from the surrounding random noise whose power is not amplified by the compression filter in the same manner.

Referring to H0 4, the compression filter 95, an acoustic surface wave device, may comprise a substrate or supporting element 107 of any suitable piezoelectric material such as quartz. for example, upon which has been formed, by any suitable process, such as vacuum deposition or photoresist techniques, two series of

fingers

108 and 109, the fingers being spaced with decreasing widths between them as shown. The input conductors 98 are connected to the fingers of the series 108 and the output conductors 99 are connected to the fingers of the series 109. The burst of pulses as exemplified by pulse 104 of FIG. 3 having the frequency varying between F,, and F,, as shown by the triangular pulse 105, emerges from the compression filter 95 at the conductors 99 after a delay, as a pulse having a compressed time of, for example, 0.1 microseconds, and an increased power, for example 25 watts.

ln acoustic surface wave devices, the electromagnetic energy received at the input terminals propagates down the surface of the piezoelectric device at an acoustic velocity dependent upon the frequency of the received signal. Thus the distance 5, between the

nearcst fingers

108A and 109A (H6. 4) is chosen relative to the distance S, between the fingers [08B and 1098 so that the time of propagation for the low frequency waves differs from the time of propagation of the high frequency waves by the interval of 0.] microseconds in a particular case. The time interval can be made large or small as desired, which is to say that the compression ratio between the time interval of the generated pulse and that of the propagated pulse can be selected to be some desired number. There is, in any event, an initial delay exemplified by the distance S, between

fingers

108A and 109A representing the time of propagation between these two fingers of the low frequency incident waves.

In actual cases, while the pulse 104 radiated by a transmitter 14 has a peak power of one watt, the signal received on the bomb 11 may be substantially attenuated to a lesser value. Particularly a bridge structure 12, as shown, having large amounts of metal surrounding the transmitter, will attenuate the transmitted signal rather severely. In such an instance the compression filter serves the useful purpose in amplifying the received signal above the surrounding noise level while at the same time keeping the size and weight of the system components to a very low value.

It is one of the purposes of the invention for the receiving system to have a target resolution of about 20 feet. That is to say the receiver can distinguish between radiations received from targets about 20 feet apart whether the radiations received are directly from a transmitter or indirectly as a reflection of that signal. In FIG. 1 this has been shown diagrammatically by the bomb ll being in the pathway of a direct signal pulse 15 and a reflected signal pulse 19. The concept of the invention is that the receiving system can distinguish between the time of arrival of the leading edges of the two pulses, The receiving system will respond to the leading edge of one pulse of appropriate power level and will reject any signal arriving more than 20 nanoseconds later. In FIG. 5 there is shown diagrammatically a direct transmitted pulse 106 which corresponds to the pulse after its reception and processing through the compression filter 95. Thus this pulse has a time span of 0.1 microseconds similar to that shown in FIG. 3. The pulse 106 also corresponds to the pulse 15 of FIG. 1 after reception and processing.

Also in FIG. 5 there is shown a reflected pulse 106A which in solid lines is shown as being of the same amplitude as pulse 106. This is for illustrative purposes only inasmuch as the reflected pulse may be larger than the directly transmitted pulse when the direct transmitter pulse has been attenuated more than the reflected as indicated. The dotted line 1068 indicates diagrammatically the fact that the reflected pulse 106A may be larger in amplitude. The leading edges of pulses I06 and 106A are shown apart by about one-half of the pulse width that is, about fifty nanoseconds.

In accordance with the inventive concept the receiver of the invention discriminates between the

pulses

106 and 106A. lt receives pulse 106, or the leading part thereof, and rejects the pulse 106A. Also in FIG. 5 there is shown a composite

pulse combining pulses

106 and 106A as well as 1068. As will be described, the receiving and discriminating circuit of the invention activates a gate (switch) to receive a pulse once the leading edge 106C of proper amplitude is re ceived and discriminates against pulses received more than 20 nanoseconds later by virtue of the fact that the gate deactivates and thus avoids receiving any further signals. The 20 nanosecond time interval is indicated by the letter D. means is shown a threshold 111 above the datum of the pulses, this threshold having a value such as to indicate that a significant signal is being received. Once a signal of threshold value is received the circuit cuts off l nanoseconds later as shown by the interval D. The remaining portion of the received signal pulse beyond the dotted line at the end of interval D as shown in the composite pulse of FIG. is ignored.

Referring to FIG. 6 there is shown a dual stage sample and hold circuit for achieving the high degree of target resolution according to the invention. The sample and hold circuit is the sample and hold circuit 51 of FIG. 2 and corresponding reference characters are used. The portion thereof to the left of the dotted line 112 corresponds to the sample and hold circuit 51 whereas the portion to the right corresponds to the switch 59 of FIG. 2 and the conductors connected thereto. The components of the sample and hold circuit 51, as shown in FIG. 6, comprise a MOSFET device (gate) 113, a capacitor 114, a fast-acting switch 115, an amplifier 116 and a second capacitor 117. The MOSFET device 113 has a source (drain) 118, a drain (source) 119 and a gate electrode 121 as is well under stood in this art. The source 118 is connected to input terminal 46, the drain 118 is connected to one terminal of the

capacitor

114 and 122 and is also connected to the input terminal of the fast-acting switch 115 which may be a solid-state device. The other terminal of capacitor 114 is grounded as shown.

The gate terminal 121 receives the signal to turn on or activate the sample and hold circuit 51 over the conductors 82 and 86 from the sequencer 81. When MOS- FET 113 is conducting. the capacitor 114, which may have a capacity value of twenty pico farads, becomes charged very rapidly because of the very small capacitance. Specifically it will charge to the desired value in nanoseconds or less. But being of a small capacity value the capacitor 114 likewise tends to discharge rapidly as well. During the time that capacitor 114 is being charged the switch 115 is open, or inactivated. However when the capacitor 114 has become fully charged the switch 115 becomes activated, i.e., closed, and the voltage stored on capacitor 114 is fed to amplifier 116 which amplifies it and supplies it in turn to a much larger capacitor 117 having a capacity value of about twotenths microfarad. This value of capacity is suffi cient for capacitor 117 to hold the voltage stored thereon and thus on conductor 55 until the switch 59 can operate and feed the voltage to the comparing circuit 66 as has been described.

The time for turning on, or activating, the MOSFET device 113, may be 2 nanoseconds, the device remains turned on for sixteen nanoseconds and about two nanoseconds are required for turning it off, or inactivating it. A total time of about twenty nanoseconds is thus taken for this operation. No later than at the end of this time interval and, in any event, before the charge on capacitor 114 has an opportunity to leak off to any significant extent, the solid-state switch is activated by a voltage pulse at conductor 115A supplied from sequencc 81 and the charge transferred through amplifier 116 to the capacitor 117. After the MOSFET device 113 is inactivated any further signals which appear on conductor 46 are ignored and do not influence the subsequent operation. Thus it is evident that any signals which are received after the 20 nanosecond interval. and would therefore belong to some other radiating target more than 20 feet away from the designated target or reflected from nearby surfaces, would not influence the operation of the guidance system. Hence target discrimination is achieved by a fast-acting dual mode sample-and-hold circuit which functions essentially on the leading edges of the pulses received.

In FIG. 7 there is shown a simplified timing diagram applicable to the described circuit. According to this diagram the interval between 0 seconds and 0.001 seconds applies to switch 32, the sample and hold 51 and the related circuitry, the interval between 0.00l seconds and 0.002 seconds applies to the switch 33, the sample and hold 52 and the related circuitry. the interval between 0.002 second and 0.003 second applies to the switch 34, the sample and hold 53 and the related circuitry, and the interval between 0.003 second and 0.004 second applies to the switch 35, the sample and hold 54 and the related circuitry. That is, each of the switches 32-35 is open for 0.001 second in succession, the timing intervals being controlled by the sequencer 81 and being indicated by the

pulses

123, 124, and 126 respectively. During each of the intervals 123-126 there is shown one of the

pulses

127, 128, 129 and 131, respectively. The pulses I27, 128, 129 and 131 corre spond to the received pulses 15 of FIG. 1 or the

compressed pulses

106 and 106A of FIGS. 3 and 5.

After all of the

pulses

127, 128, 129 and 131 have been received in the respective channels and the voltages corresponding thereto exist on the capacitor 117 for each of the sample and hold circuits, the sequencer 81 supplies a control signal over conductor 92 which appears as pulse 132 (FIG. 7). The pulses 132 activate the switches 59, 61, 62 and 63 whereby the voltages ex' isting on the capacitors 117 etc. are passed to the comparators 66 and 69 for comparison of the azimuth and elevation signals following which the differences are supplied through conductors 71 and 73 to the integrators 72 and 74 for passage to the elevational control and azimuth control as previously indicated.

A complete description of the operation of the systern together with additional structure may be understood and described by considering an example of op eration. For this purpose it may be assumed that a bomb carrying a guidance system according to the invention has been launched into the area and toward the target desired. The guidance circuit will be operational and the sequencer 81 will cause the control pulses to go to the various components as described. In the first instance, it may be assumed that insufficient signal level is being received from any transmitting source to effect the guidance system and no output (control) signals are developed thereby. This may be understood by referring to the composite signal of FIG. 5 and noting that any signal less than amplitude shown by the threshold value 11] will not cause the sample and hold circuits to become functional, no signals will be received effectively, and the guided bomb control surfaces will remain inactive. The threshold detector 102 may be of any well'known type which is amplitude sensitive and determines when a signal of appropriate value. namely that of threshold value 11] is received.

After the bomb has moved some distance toward the target it may be assumed that the received pulses l5 and 19 (FIG. 1) either singly or as a composite will have sufficient amplitude for the threshold value of 1 ll to be exceeded. These pulses are exemplified by the

pulses

127, 128, 129 and [SI of the timing diagram FIG. 7. Upon receipt of these signals in sequence, the various sample and hold circuits function and voltages are stored on the

capacitors

114 and 117 in each of the channels. Referring to FIG. 7 and considering the interval between and 0.00l seconds when the switch 32 is activated for one-thousandth of a second as shown by the pulse 123, it is shown that after a partial lapse of this time interval the signal pulse 127 (106) is received and is of sufficient amplitude to cause the threshold detector 102 to supply an appropriate signal to the sequencer 81 through conductor 103. whereupon the sequencer supplies a signal over conductor 86 to the gate terminal 121 of MOSFET device 113. The sample and hold circuit 51 is thus activated and voltage is supplied to capacitor 114 in accordance with the received pulse signal.

After a twenty nanosecond lapse, interval D, the sequencer deactivates or turns off the MOSFET 113 and any signals of whatever amplitude thereafter do not get into the circuit and do not influence the result. The signals are cut off. Thus even though there may be an other transmitter in the area transmitting a signal of larger amplitude for one reason or another, this signal has no influence because it has occurred more than ten nanoseconds after cut off. The same phenomenon takes place during each of the subsequent intervals namely during the

pulses

124, 125 and 126. Thus during each total interval of four thousandths of a second, four measurements, or pulses, are received, two of which are utilized to energize the elevational control and the remaining two are utilized to energize the azimuth control.

An ordinary bomb at its terminal velocity may be moving in the vicinity of eight hundred feet per second and to direct its course effectively the control of its azimuthal and elevational surfaces need be updated only about once every second or thereabouts. During an interval of one second about one thousand signals are received by the circuit and processed, and an appropriate value is entered in the integrating circuits 72 and 74 for utilization as an average to alter the control surfaces.

It will be understood, of course, that the time intervals may be varied to suit the particular circumstances.

While a two-stage, fast sample-and-hold circuit has been shown, according to the invention, for discriminating between pulses from different sources and to give the desired target resolution it will be understood that other discriminating circuits may be devised without departing from the spirit and scope of the system of the disclosure.

In addition, while a pulse compression filter of one particular type has been shown to lower peak power requirements and provide narrow pulses in the receiver for resolution. other types of pulse compression could be devised or not employed at all without departing from the spirit and scope of the system of this disclosure.

I claim:

1. A control system for guiding an object in azimuth and elevation toward a radiating target comprising:

a series ofsensors adapted to be disposed on such object for receiving such radiation and being adapted for determining azimuthal and elevational information;

a processing circuit for the signals from said sensors;

a first series of fast acting switches one each of which is connected between one each of said sensors and said processing circuit;

each one of said first series of switches including means for setting the on and off condition of the respective switch;

a series of sample and hold means one each for each of said sensors connected to receive the signals from the processing circuit;

each one of said series of sample and hold means including means for setting the on and off condition of the respective sample and hold means;

an azimuthal signal comparator and an elevational signal comparator;

a second series of fast acting switches one each of which is connected to one each of said sample and hold means, respectively, azimuthally related ones of said second series of fast acting switches being connected to said azimuthal signal comparator and elevationally related ones of said second series of fast acting switches being connected to said elevational signal comparator;

each one of said second series offast acting switches including means for setting the on and off condition of the respective switch;

sequencing means connected to the setting means of said first series of fast acting switches and to the setting means of said sample and hold means for simultaneously and sequentially turning on and off related ones of said first series of fast acting switches and said sample and hold means;

said sequencing means further being connected to the setting means of said second series of fast acting switches for sequentially initiating comparison in said azimuth signal comparator of said azimuth signals and in said elevation signal comparator of said elevation signals;

means for supplying the compared signal of said azimuth signal comparator to azimuth control means; and

means for supplying the compared signal ofsaid elevation signal comparator to elevation control means.

2. The control system according to claim 1 wherein the fast acting switches are solid state devices.

3. The control system according to claim 1 wherein the means for supplying the compared signal of said azimuthal signal comparator to azimuth control means comprises integrating means and wherein the means for supplying the compared signal of said elevational signal comparator to elevation control means comprises further integrating means.

4. The control system according to claim 1 wherein the signal processing circuit comprises signal to noise ratio enhancement means.

5. The control system according to claim 4 wherein the signal to noise ratio enhancement means comprises pulse compression means.

6. The control system according to claim wherein the pulse compression means comprises acoustic surface wave transducing means.

7. The control system according to claim 1 wherein each of said sample and hold means comprises a fast sample and hold means and a slow sample and hold means in series.

8. The control system according to claim 5 including signal threshold detecting means for said fast sample and hold means.

9. The control system according to claim 8 wherein the fast sample and hold means comprises a field-effect transistor and a capacitor, said field-effect transistor being turned on and off by said sequencing means.

10. A control system for guiding an object in azimuth and elevation toward a radiating target comprising:

a series of sensors adapted to be disposed on such object for receiving such radiation and being adapted for determining azimuthal and elevational information;

a processing circuit for the signals from said sensors;

a series of pulse discriminating means one each for each of said sensors connected to receive the signals from the processing circuit;

each one of said series of pulse discriminating means including means for setting the on and off condition of the respective pulse discriminating means;

an azimuthal signal comparator and an elevational signal comparator;

a second series of fast acting switches one each of which is connected to one each of said pulse discriminating means, respectively, azimuthally related ones of said second series of fast acting switches being connected to said azimuthal signal comparator and elevationally related ones of said second series of fast acting switches being connected to said elevational signal comparator;

each one of said second series of fast acting switches including means for setting the on and off condition of the respective switch;

sequencing means connected to the setting means of said first series of fast acting switches and to the setting means of said pulse discriminating means for simultaneously and sequentially turning on and off related ones of said first series of fast acting switches and said sample and hold means;

means for supplying the compared signal of said ele vation signal comparator to elevation control means.

11. A control system for guiding an object in azimuth and elevation toward a radiating target comprising;

a processing circuit for the signals from said sensors including pulse compression means.

signal threshold detecting means;

each one of said first series of switches including means for setting on and off condition of the respective switch;

an azimuth signal comparator and an elevational signal comparator;

a second series of fast acting switches one each of which is connected to one each of said sample and hold means, respectively, azimuthally related ones of said series of fast acting switches being connected to said azimuthal signal comparator and elevationally related ones of said second series of fast acting switches being connected to said elevational signal comparator;

sequencing means connected to the setting means of said first series of fast acting switches and to the setting means of said sample and hold means for simultaneously and sequentially turning on and off related ones of said first series of fast acting switches and, in response to said signal threshold detecting means, said sample and hold means;

said sequencing means further being connected to the setting means of said second series of fast acting switches for sequentially initiating comparison in said azimuth signal comparator of said azimuth signals and in said elevation signal comparator of said elevation signals,

means for supplying the compared signal of said azimuth signal comparator to azimuth control means, and

means for supplying the compared signal of said elevation signal comparator to elevation control means.

12. The control system according to claim ll wherein said series of sensors comprises two wide beam elevational information sensing antennas and two wide beam azimuthal information sensing antennas disposed in quadrature relative to each other on the front of said object;

13. A control system for guiding an object in azimuth and elevation toward a radiating target comprising;

a series of sensors adapted to be disposed on such object for simultaneous exposure to such radiation and being adapted for determining azimuthal and elevational signals;

means for sequentially sampling in continuous cycles the signals on said sensors and holding the sampled signals until all sensors have been sampled in each cycle;

utilization means, respectively.

15. The control system according to claim 14 including means for improving the signal to raise ratio of the signals on said sensors;

means for detecting a threshold value of said signals and preventing sampling and holding of such signals unless at least equal to said threshold value; and

means for discriminating against extraneous pulses.

k i I. i

Claims

1. A control system for guiding an object in azimuth and elevation toward a radiating target comprising: a series of sensors adapted to be disposed on such object for receiving such radiation and being adapted for determining azimuthal and elevational information; a processing circuit for the signals from said sensors; a first series of fast acting switches one each of which is connected between one each of said sensors and said processing circuit; each one of said first series of switches including means for setting the on and off condition of the respective switch; a series of sample and hold means one each for each of said sensors connected to receive the signals from the processing circuit; each one of said series of sample and hold means including means for setting the on and off condition of the respective sample and hold means; an azimuthal signal comparator and an elevational signal comparator; a second series of fast acting switches one each of which is connected to one each of said sample and hold means, respectively, azimuthally related ones of said second series of fast acting switches being connected to said azimuthal signal comparator and elevationally related ones of said second series of fast acting switches being connected to said elevational signal comparator; each one of said second series of fast acting switches including means for setting the on and off condition of the respective switch; sequencing means connected to the setting means of said first series of fast acting switches and to the setting means of said sample and hold means for simultaneously and sequentially turning on and off related ones of said first series of fast acting switches and said sample and hold means; said sequencing means further being connected to the setting means of said second series of fast acting switches for sequentially initiating comparison in said azimuth signal comparator of said azimuth signals and in said elevation signal comparator of said elevation signals; means for supplying the compared signal of said azimuth signal comparator to azimuth control means; and means for supplying the compared signal of said elevation signal comparator to elevation control means.

6. The control system according to claim 5 wherein the pulse compression means comprises acoustic surface wave transducing means.

10. A control system for guiding an object in azimuth and elevation toward a radiating target comprising: a series of sensors adapted to be disposed on such object for receiving such radiation and being adapted for determining azimuthal and elevational information; a processing circuit for the signals from said sensors; a first series of fast acting switches one each of which is connected between one each of said sensors and said processing circuit; each one of said first series of switches including means for setting the on and off condition of the respective switch; a series of pulse discriminating means one each for each of said sensors connected to receive the signals from the processing circuit; each one of said series of pulse discriminating means including means for setting the on and off condition of the respective pulse discriminating means; an azimuthal signal comparator and an elevational signal comparator; a second series of fast acting switches one each of which is connected to one each of said pulse discriminating means, respectively, azimuthally related ones of said second series of fast acting switches being connected to said azimuthal signal comparator and elevationally related ones of said second series of fast acting switches being connected to said elevational signal comparator; each one of said second series of fast acting switches including means for setting the on and off condition of the respective switch; sequencing means connected to the setting means of said first series of fast acting switches and to the setting means of said pulse discriminating means for simultaneously and sequentially turning on and off related ones of said first series of fast acting switches and said sample and hold means; said sequencing means further being connected to the setting means of said second series of fast acting switches for sequentially initiating comparison in said azimuth signal comparator of said azimuth signals and in said elevation signal comparator of said elevation signals; means for supplying the compared signal of said azimuth signal comparator to azimuth control means; and means for supplying the compared signal of said elevation signal comparator to elevation control means.

11. A control system for guiding an object in azimuth and elevation toward a radiating target comprising; a series of sensors adapted to be disposed on such object for receiving such radiation and being adapted for determining azimuthal and elevational information; a processing circuit for the signals from said sensors including pulse compression means; signal threshold detecting means; a first series of fast acting switches one each of which is connected between one each of said sensors and said processing circuit; each one of said first series of switches including means for setting on and off condition of the respective switch; a series of sample and hold means one each for each of said sensors connected to receive the signals from the processing circuit; each one of said series of sample and hold means including means for setting the on and off condition of the respective sample and hold means; an azimuth signal comparator and an elevational signal comparator; a second series of fast acting switches one each of which is connected to one each of said sample and hold means, respectively, azimuthally related ones of said series of fast acting switches being connected to said azimuthal signal comparator and elevationally related ones of said second series of fast acting switches being connected to said elevational signal comparator; each one of said second series of fast acting switches including means for setting the on and off condition of the respective switch; sequencing means connected to the setting means of said first series of fast acting switchEs and to the setting means of said sample and hold means for simultaneously and sequentially turning on and off related ones of said first series of fast acting switches and, in response to said signal threshold detecting means, said sample and hold means; said sequencing means further being connected to the setting means of said second series of fast acting switches for sequentially initiating comparison in said azimuth signal comparator of said azimuth signals and in said elevation signal comparator of said elevation signals, means for supplying the compared signal of said azimuth signal comparator to azimuth control means, and means for supplying the compared signal of said elevation signal comparator to elevation control means.

12. The control system according to claim 11 wherein said series of sensors comprises two wide beam elevational information sensing antennas and two wide beam azimuthal information sensing antennas disposed in quadrature relative to each other on the front of said object.

13. A control system for guiding an object in azimuth and elevation toward a radiating target comprising; a series of sensors adapted to be disposed on such object for simultaneous exposure to such radiation and being adapted for determining azimuthal and elevational signals; means for sequentially sampling in continuous cycles the signals on said sensors and holding the sampled signals until all sensors have been sampled in each cycle; means effective after said sampling sequence in each cycle for comparing the held azimuthal signals and the hold elevational signals; and means for transmitting said compared azimuthal data to azimuth utilization means and said elevational signals to elevation utilization means.

14. The control system according to claim 13 including means for separately accumulating the compared azimuthal signals and the compared elevational signals prior to transmitting same to azimuthal and elevational utilization means, respectively.

15. The control system according to claim 14 including means for improving the signal to raise ratio of the signals on said sensors; means for detecting a threshold value of said signals and preventing sampling and holding of such signals unless at least equal to said threshold value; and means for discriminating against extraneous pulses.