US2421017A - Communication and guiding system - Google Patents
Communication and guiding system Download PDFInfo
- Publication number
- US2421017A US2421017A US534284A US53428444A US2421017A US 2421017 A US2421017 A US 2421017A US 534284 A US534284 A US 534284A US 53428444 A US53428444 A US 53428444A US 2421017 A US2421017 A US 2421017A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/14—Relay systems
- H04B7/15—Active relay systems
- H04B7/155—Ground-based stations
- H04B7/17—Ground-based stations employing pulse modulation, e.g. pulse code modulation
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S1/00—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith
- G01S1/02—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith using radio waves
Definitions
- This invention relates to communication and guiding systems and more particularly to a system for communicating with a moving craft or other mobile communication unit and for guiding a craft or unit along a particular route.
- the systems of beacons for guiding crafts along a given course may comprise a series of radio beacons overlapping in space at points along the course with provisions, such as marker beacons, intermediate the radiation patterns of the separate beacons in the region of the overlapping patterns warning when to change over for reception from a new beacon system.
- the receiver on the craft is tuned in response to a change of frequency from one beacon to another so that the indicator will switch over without special attention of the pilot.
- this type of beacon system no provision is made to cause the craft indicatorto change its reception condition from one beacon to another at substantially the same point regardless of the direction of travel. Because of the inherent bias or sensitivity level needed to effect the control for changing the receiver tuning, this type of proposed beacon arrangement will cause the craft receiver to shift its reception condition at difierent points along the course depending on the direction of travel of the craft.
- a multiplex communication system in which a plurality of channels are transmitted from a single terminal station over a plurality of successive towers.
- radio beacons At each of the towers, or at selected ones of the towers, are arranged radio beacons so aligned that energy from said beacons will slightly overlap the energy radiated from each succeeding beacon.
- the energy from successive towers is radiated at slightly different frequencies to avoid danger of du licate reception. In the simplest form only two difierent frequencies alternate along the course. However, more frequencies may b used if desired, the frequency distributions to the different towers preferably being repeated successively along the course.
- each of the towers or at selected ones of the towers are branched off one or more communicating channels for broadcasting to the craft travelling along the course.
- the craft travelling along the course are each provided with receiving equipment for simultaneously receiving the branched off channel signals as well as the guiding beacon signal and fo segregating these signals to provide separate indications.
- receiving equipment for simultaneously receiving the branched off channel signals as well as the guiding beacon signal and fo segregating these signals to provide separate indications.
- on the craft is provided some means responsive to the received energy for rendering the receiving circuit responsive only to one of the successive frequencies.
- a separate marker beacon is provided adjacent the beginning of one of the beacon courses in the region of overlap of the two adjacent beacons.
- This marker beacon preferably transmits a relatively narrow fan shaped beam of energy upwardly, the energy being characterized by the same frequency as the beacon whose radiation pattern overlaps the pattern of the next necessary beacon.
- the craft is preferably provided with other communication equipment permitting transmission of signals from the craft to the towers along the course for communication with the base station or for communication between separate craft travelling along the course.
- the multiplex communication channels will each consist of a series of pulses separated properly in time so that they will interleave one with another. These pulses may be modulated in any suitable manner to provide pulse amplitude modulation or time displacement modulation Or any other desired type of modulation.
- the particular type of modulation circuit used is not a feature of the present invention.
- the communication between the tower and the plane and the signals sent over the communication system may be of any desired form.
- the beacon signals are of a relatively low frequency, for example, the normal 90-150 cycle tone frequencies or the known form of A-N keyed signals.
- the communication channels are preferably modulated pulse channels which may be readily separated from the guiding signals in the aircraft receiver by means of a clipper device so that segregation of the two channels may be accomplished without heavy and complicated equipment.
- the successive towers and beacons are normally inoperative to broadcast to the craft or to transmit beacon guiding signals and at each tower or station is provided means responsive to signal from a craft in the vicinity thereof to transmit beacon signals, and/or to broadcast communication signals.
- special signals from the base station may be transmitted to the towers for the purpose of rendering the beacon and/or broadcast communication operative. Both these selective systems may be incorporated in a common system, if desired.
- the beacon may be used for guiding and/or establishing communication with any type of mobile unit in the vicinity of the system.
- Fig. 1 is a diagrammatic view in perspective i1- lustrating two terminals of a multi-channel communication and guiding system together with a chain of relay stations therebetween;
- Fig. 2 is a block diagram of the west terminal station of a system such as shown in Fig. 1;
- Fig. 3 is a diagram partly in block of circuits illustrating the repeater tower equipment shown in Fig. 1;
- Figs. 3A and 3B are block circuit diagrams of portions of the equipment shown in Fig. 3;
- Fig. 4 is a block circuit diagram of a craft receiver circuit for use with the system shown in Figs. 2 and 3;
- Fig. 4A is a curved used in explaining the operation of the selector feature of Fig. 4;
- Fig. 5 is an elevational diagram of a beacon system in accordance with our invention illustrating the distribution of the various radiation field patterns
- Fig. 6 is a diagrammatic sectional plan view along line 6--6 of the radio beacon field patterns illustrated in Fig. 5;
- Fig. 7 is a set of curve diagrams illustrating operation of equipment shown in Figs. 2, 3 and 4;
- Fig. 8 is a wiring diagram of a time modulator of the type which may be used with our system
- Fig. 9 is a wiring diagram of selector and demodulator circuits usable with a system in accordance with our invention.
- Fig. 10 is a circuit diagram of a pulse width selector which may be used in Figs. 2 and 3;
- Fig. 11 is a graphical illustration used for illustrating the operation of the circuit of Fig. 10;
- Fig. 12 is a block diagram of a modified form of equipment which may be used at a terminal station
- Fig. 13 is a block diagram of a tower equipment circuit arranged for use with a terminal station, such as shown in Fig. 12;
- Fig. 14 is a block diagram of an aircraft communication equipment arranged for cooperation with the system of Fig. 13;
- Fig. 15 is an elevational diagram of a modified beacon arrangement similar to that shown in Fig. 5;
- Fig. 16 is a block circuit diagram illustrating the modified transmitter equipment used to produce the beacon arrangement of Fig. 15;
- Fig. 1'7 is a block circuit diagram of a receiver arrangement for response to signals such as transmitted from the circuit of Fig. 16.
- FIG. 1 there are provided two terminals l and I2 (west and east) interconnected by a chain of relay tower stations l3, l4 and I5.
- Each of the towers is provided with a plurality of antennas 2
- Energy is transmitted from west to east with different characteristics between alternate towers, for example, at Slightly different radio frequencies Fl, F2, as shown in the drawing.
- each of the towers are a plurality of guiding beacon transmitting antennas 26 preferably provided with a directive reflector arrangement 26A.
- These beacons transmitters may operate at the alternate frequencies corresponding to the alternate frequencies Fl and F2, transmitted from the towers in the west-east direction. It should be clear that, if desired, the beacons may be arranged to cooperate with the east-West channels instead.
- At each of the intermediate towers in the zone of overlap of the directive radio beacon signals are provided separate marker beacon transmitting antennas 25 operating at a particular signal characteristic, for example, at the frequency corresponding to the next preceding radio beacon pattern.
- the arrangement of the guiding beacon and marker beacon system is provided for assuring that craft travellin along a line defined by the beacons will be enabled to switch from the reception of one of the frequencies to the next adjacent one in substantially the same area, regardless of the direction of travel of the craft. This function will be explained more fully in detail later.
- FIG. 1 A better understanding of the system shown in Fig. 1 may be had from the particular description of one embodiment of our invention as illustrated in Figs. 2, 3 and 4.
- the west terminal is shown to include a switchboard 50 containing jack connections for outgoing and incoming channels l-N and la-Na, respectively.
- the switchboard is of known character provided for connectin telephone circuits or trunk lines to the proper channel jacks and also for connecting together incoming and outgoing channels under certain circumstances described hereinafter.
- Channel includes a modulator 5
- and also all others from modulator 52 to the modulator for channel N may be of any desired type but are preferably of the character for producing push-pull time displacement modulation of pulses. In order to effect this time modulation, energy from a base wave source 60 is applied over individual phase shifters 62-41, etc., for channels 2 through N, respectively.
- Channel I need not have an individual phase shifter since the phase of the wave from source 60 may be applied directly without phase shift to the modulator 5
- the phase shifters for the other channels are adjusted so that the individual trains of pulses for the separate channels will be displaced in time to provide a single resultant train in the common output 10.
- Channel I has been chosen as the synchronizing and monitoring channel and, as such, is given a particular width Wl by shaper 58.
- the pulses of the other channels may be given a difierent width W2 in shaper 58a.
- All the trains of pulses produced by the different channel modulators are combined, as indicated by the output connections at 10, and applied to an R.--F. translator l4 and radiated by transmitting antenna 2
- the R.-F. translator in this instance will provide a carrier wave of frequency Fl, as indicated in Fig. 1.
- This train of multiplex channel pulses is east bound, channel operating as a synchronizing and monitoring channel for controlling the separation of channel pulses at the receivers whether in a plane or at the east terminal l2.
- modulator I6 In order that selected ones of the channels may be broadcast at terminal l0, another modulator I6 is provided. This modulator is coupled to the selected channels to be broadcast transmitted at a wider angle for communication with craft. Separate couplers 7-8 are provided to prevent the other channels coupled in parallel to line 10 from also feeding to modulator 16. These branched signals are then transmitted from antenna 23 for a purpose of communication with craft as will be more readily understood when the particular description of Fig. 4 is given.
- Energy from the pulse width selector is also applied to the deblocking selectors of the other receiving channels, the energy being applied through suitable delay devices for proper timing.
- the deblocking pulse is applied to a delay device and thence to deblocking selector 92 where it controls the selection of the pulses of channel 2a, as received over line 9
- the channel pulses passed by the selector 92 are applied to demodulator 94 whereby the time displacement of the video pulses is translated into an audio signal wave which, in turn, is applied over line 95 to the proper jack on the switchboard 50.
- This selector control is the same for the additional channels 311 to Na and therefore need not be illustrated or described in detail.
- the return communication signals from the craft in the vicinity from the west base terminal are received on antenna '24 and detected to audio frequencies in a suitable detector arrangement l5.
- Detector 15 is provided with a channel selector system for separating the received signals in accordance with the selected channel and applying these signals to individual lines 11.
- a suitable selector for this purpose may be made in accordance with the teachings hereinafter more fully explained in connection with Fig. 3B.
- the separate output lines are connected over a cable 19 to the individual terminals Ia, 3a, 5a, Ia, etc., of switchboard 50.
- Fig. 3 is disclosed in more detail a typical block circuit diagram of the equipment provided with the repeater tower.
- the repeater circuit there are provided four directive antenna arrangements 2
- From the antenna 22 are applied pulses to the outbranching circuit I which serves to select the channels it is desired to transmit from antenna 23 for reception on the separate craft.
- These output signals are applied to antenna 23 over line IOI.
- Carrier source 36 supplies energy at frequency F2 to energize beacon modulator 31 and the outbranching circuit I00.
- the energy received from the craft is applied from antenna 24 over line I03 to inbranching circuit I05 from whence it is supplied to antenna 22A together with signals from west bound transmitter 41.
- Energy from oscillator 48A is applied at frequency F3 to transmitter 41 and inbranching circuit I05.
- the inbranching circuit is timed by energy from receiver 43 as indicated by line I05a.
- the marker beacon antennas 25 are energized by transmitter I02 operating at the frequency FI, the same as that received on receiving antenna 22.
- 24 and 25 are preferably mounted above a shielding sheet I04 mounted on the associated tower. This sheet serves as an artificial ground for these antennas.
- the guiding beacon antennas 26 are provided within an angular reflector 26A which may be mounted on the tower in the manner illustrated in Fig. 1.
- the reflector arrangement is adjusted to cause the beacon antenna system to operate substantially unidirectionally.
- the horizontal portion of reflector 26A serves as an artificial ground to prevent much of the beacon energy from being radiated earthward to cause troublesome reflections and the consequent false course indications. It should be understood that, if the spacing above ground causes an unduly large number of lobes in the vertical plane, or too much trouble from ground reflection, the beacon antenna may be mounted directly adjacent the ground and the area therearound suitably cleared to prevent undesired refleeting action.
- the beacon antenna is illustrated only diagrammatically since the specific form of beacon used is not material to the principles of our invention. It is preferable to make this beacon as simple as possible and of such construction that little service is needed. Likewise, it is clear that the modulation may be produced either by keying the antennas alternately to shift the pattern or by modulating with different tone frequencies, such as 150 and 90 cycle tones commonly used in radio course beacons at the present. Moreover, each beacon may be caused to transmit identifying signals if desired as well as the directive indications.
- a detector I06 which detects the incoming waves to a video frequency. Since detection will generally take place in receiver 3I if the pulses are to be transmitted at a different R. F. detector I06 may be omitted and the signal taken from the output of this receiver.
- the detected pulse envelope is applied to pulse width selector I08 which serves to select out the shaped pulses of channel I. These pulses are then reshaped, if necessary, in shaper I I0 after which they are applied over line I33 to modulator I34.
- the selected pulses from the output of I08 are also branched over delay circuits I I3, H5, H1, I I9 and I2I and shapers H4, H6, H8, I20 and I22, respectively, and applied to channel selectors I24, I26, I28, I30 and I32, respectively with the channel Signals from detector I06 to select the pulses corresponding to channels 3, 5, 1, 9 and I I, for example.
- These selected channels properly timed with respect to channel I are then applied from the output of the respective selectors to line I33 from whence they are all applied to modulator I34.
- the output of modulator I34 is connected by means of line IOI to antenna 23, as shown in Fig. 3.
- the selected channels are broadcast for selection and reception by craft within the field of the communication system.
- the in-branching circuit I05 may best be understood by reference to Fig. 3B.
- the input line I03 is shown as connected to a detector I40 which serves to detect the received radio frequency to video frequency producing in the output a plurality of pulses corresponding to the channels received by antenna 24.
- each of these channels is represented by pulses of different widths.
- separate width selectors and demodulators are provided, as shown at I4I, I43, I45, I41, I49 and I5I.
- selector MI is provided a base Wave generator I60 which is controlled by selector synchronzer I60a to produce a suitable base wave for timing these received channels for insertion into gaps in the east-west multiplexing channel of the system.
- Fig. 4 is illustrated a typical receiver circuit for use on a craft, such as an aircraft, for receiving the communication and guiding signals from the tower of the system in accordance with our invention.
- aircraft receiving antenna I which receives the beacon signals and the communication signals transmitted from the tower by means of antennas 23 and 26.
- Antenna I80 is preferably coupled to a broad band receiver I8
- amplifying filter arrangements I82, I84 tuned to pass frequencies FI and F2, respectively.
- the output from I84 may be applied to an automatic volume control circuit I86 which serves to bias I82 so that substantially no energy at FI passes.
- an automatic volume control circuit I86 which serves to bias I82 so that substantially no energy at FI passes.
- the craft passes to a region where Fl predominates A. V. C. circuit I88 in the output of I82 biases circuit I84 so that substantially no energy at frequency F2 is passed.
- the receiver on the craft is made to respond to one of these signals to the exclusion of the other. It should be understood that other signal characteristics different from frequency discriminations may be used to operate the receiver switching if desired.
- the receiver energy is then detected in detector I81 to provide an envelope of the form shown in Fig.
- This envelope has a low frequency wave component 2I5 corresponding to the beacon signals and a pulse component 2I8 corresponding to the pulse communication signals.
- This composite wave from the output of detector I81 is applied to a limiter I90 which serves to clip or limit the envelope at a level 2I1 preferably substantially at twice the average incoming carrier frequency so that the low frequency envelope 2I5 will be passed but the high energy pulses will be limited in amplitude.
- the output of limiter I90 is then applied to a selective filter I9I which serves to remove the higher frequency pulse components still remaining and this output signal is then applied to a guide indicator I92 or to other visual or audible indicators, if desired.
- the envelope wave is also passed to a clipper I93 which serves to remove the portion of the envelope below clipper level 2" to separate the incoming pulses from the lower frequency envelope and apply them to the selective circuit.
- a pulse width selector I94 which serves to select the pulses of channel I and apply them to a demodulator circuit I95 from which they are applied to headphones or other audible signal source I96.
- These pulses of channel I are preferably order channel impulses used for communicating to all of the planes or other craft in the region and also may serve for selecting another channel.
- the pulses from the output of pulse width selector I94 are applied to an adjustable delay circuit I91 which serves to adjust the delay of the pulses in the output of this selector to a proper position for selection of other communication channels from among those received at I8I.
- These output pulses are applied to a deblocking selector I98 together with the clipped pulses from the output of clipper I93.
- selector I98 the desired channel is selected by adjustment of delay circuit I91 and these selected pulses are applied to demodulator circuit I99 and from there to headphones 289.
- a microphone 20I is associated with the other channel receiver I96 and applies pulses to a pulse modulator 282.
- a control wave source 293 is provided for properly timing modulator 292. If desired, the control wave source may be synchronized with the output pulses from adjustable delay network I91 or directly from the output of selector I94. This control wave, together with the audio signals from 281, produce in the output of modulator 222 pulses time displaced in accordance with the signalling energy applied. These output pulses are then shaped to a desired Width in pulse shaper circuit 284 and applied to radio fre-.
- a wave of carrier frequency F5 is also applied to modulator '2 from a source 2I8- so that the combined signals may be radiated from antenna 2 I2 for reception on antennas 24 of the link channel.
- a communication channel transmitter including a microphone 206 and a pulse generator and modulator 201.
- Output energy from control wave generator 283 is applied over a phase shifter 205 to pulse generator 201 for the purpose of properly timing these pulses to prevent overlapping of the pulses from modulator 282.
- the output pulses from modulator 281 are applied to a pulse shaper 208 which serves to adjust the pulses in width to correspond with any one of the channels Ia, 3a, 5a, 1a, 9a and Ila, which are used for communication between the plane or other craft and base station. These pulses are then also applied to modulator 2I I for transmission over antenna 2I2.
- each of the communication mediums for the two directions comprises a series of repeaters having field patterns shown diagrammatically in Fig. 5 at 220, 22I, 222, 223 and 224 for the eastbound traffic and 240, 24I, 242, 243 and 244 for the westbound traffic.
- the beacon signals transmitted from the succession towers are shown at 225, 226, 221 and 228 of Fig. 5.
- This unidirectional pattern is preferably made to have considerable energy component in the vertical plane so that aircraft may follow the course at many different altitude levels.
- each of these guiding beacon patterns is produced by two relatively narrow overlapping patterns 225, 225a, 226, 226a, 221, 221a, 228 and 228a, as can be more clearly seen in Fig. 6.
- an aircraft such as shown at 222A proceeding from the west to east would have to cross the boundary of the overlapping zone of radiation patterns 228 and 221 to some point such as indicated by the dot 225A before the automatic switching could take control.
- an ai fq fafil such as 2223 travelling in the 0pposite direction, would have to pass out of the influence of radiation pattern 227, for example, and considerably into the field of the next succeeding radiation pattern 226 to some point, such as shown at 225B before the switching over of the receiver would be effective. This would result in aircraft travelling in opposite directions switching over their control at different points along the path.
- Such variation in switching points is generally not desirable particularly in view of the communication with the base station mounted on similar type receivers.
- the additional marker beacons 230, 23!, 232 and 233 may be provided. These beacons, as shown, are made to have patterns slanting forward in the direction of the repeater stations because of the particular characteristic shape of the guiding beacon radiation patterns. Thus, craft 222A travelling west to east from one beacon to another will still be switched at substantially the same point 225A.
- craft 222B travelling in the opposite direction will have its receiver switched by means of the energy in the marker beams 230 to 233, respectively, so that the switching over will take place in substantially the same area as that of planes travelling west to east. In the case of plane 222B, for example, it will be switched over at about point 225C.
- These marker beams are preferably made relatively narrow in the line of travel of the craft and relatively wide transversely thereto as shown in Figs. and 6.
- Fig. 6 may be considered as a plan view in cross section along lines 6-6 of Fig. 5. This type of illustration is preferable since the marker beams 230-233 are arranged at an an e d a accurate plan view would therefore be less clear.
- beacons While we have shown preferably the use of unidirectional radio beacons, it is clear that bidirectional beacons may be used, if desired. Likewise, it is clear that the beacons need not be provided at each repeater station but may be provided at discretely placed intervals so that adequate overlapping patterns are produced.
- curve a represents several trains of pulses corresponding to the respective channels. It will be seen that the succeeding channels I to l2 for example, are spaced in time so that they do not overlap. Likewise, channel I is shown to be composed of pulses of a different width from the other channels for the purpose of selectively timing the remote receiving equipment. The timing of the channels at the transmitting end, for example, at the west base, may be accomplished by means of apparatus described more fully in connection with Fig. 8.
- a rectified wave 250 may be provided to produce channel I and by phase shift a different rectified wave I used for production of the next succeeding channel. The progressive phase shift of the control wave may be used successively to time the other channels of the system in a similar manner.
- the selected channels I, 3, 5, 1, 9 and H are illustrated in extended form with respect to the showing of curve (1.
- These pulses may, for example, represent the substantially evenly spaced pulses branched out at the control towers for communication with the craft. Separation or selection of the channels may be obtained by delaying pulses l different amounts so that they coincide in position with the pulses of successive channels, 3, 5, l, 9 and l I, as shown in curve d. If these pulses are then combined and clipped at level 252, the channels may be separated out from the entire group of channels. For example, if a single channel is to be selected as shown in curve e pulse I will be delayed to position it in time to coincide with channel 5 for the selection of this particular channel.
- pulses of different width which may be used on the craft to indicate separate reply channels lb, 3b, 5b, 1b, 9b and llb which may correspond to the channels I, 3, 5, 1, 9 and II transmitted to the craft.
- These separate channels are selected at the tower in accordance with pulse width, as was explained more particularly in connection with Fig. 3B.
- a more complete description of the pulse width selector apparatus is made hereinafter in connection with Figs. 10 and 11.
- Coils 301 and 308 are coupled to a pair of triode amplifiers 309 and 3l0 asymmetrically biased by batteries 3! I, 3l2 for operation in the manner of an offset full-wave rectifier.
- the base wave of generator 60 preferably has a frequency corresponding to the desired cadence frequency T of the pulses to be produced.
- tubes 309 and 3l0 operate in efiect as an offset full-wave rectifier, an output wave of the form shown at 3
- This wave is applied to a pulse shaper 314 which clips and shapes the cusps of wave 3! to produce a plurality of unevenly spaced pulses (see dotted line pulses of pulse train 3
- 0 is changed producing pulses having different displacement in pushpull as indicated by curve 3
- This displacement represents applied energy of one sign, for example, positive.
- Fig. 8 discloses a modulator circuit for block 5
- FIG. 9 A typical demodulator circuit for time modulated pulses is shown in Fig. 9. This circuit corresponds to the combination of deblocking selector BI and demodulator arrangement 84 hereinbefore referred to in Fig. 2. It should be distinctly understood, however, that the demodulator 84 of this circuit may be used for demodulation in the other parts of the system.
- the train of pulses 32I is fed over line 83a to mixer tube 320 of the deblocking selector 92.
- deblocking pulses 323 from delay circuit 90 (Fig. 2) are fed to another separate grid of tube 320 over line 322.
- These deblocking pulses serve to produce, in conjunction with the selected incoming pulses timed to add hereto, an output series of pulses from tube 320.
- the delay line will operate to provide a series of rectangular pulses, 323 timed in spaced relation according to the pulses of channel 3.
- These combined pulses may have the form shown in curve 6, Fig. 7.
- Tube 320 is also biased to serve as a clipper so that only the boosted pulses of the selected channel appear in the output thereof.
- a D. C. restorer rectifier tube 330 may be provided across the input of the deblocking pulses 323 to assure that the incoming deblocking pulses are of a proper level to work with the clipper circuit of tube 320 to leave only the desired output pulses above clipping level.
- the output pulses from tube 320 have the same cadence frequency T as the original modulated pulses 3l5 from modulator 303, Fig. 8.
- the pulses are applied to the control grid of a demodulator tube 349 and cause tuned circuit 3M connected to another grid of this tube to oscillate at the tuned frequency producing in the tube 349 a combined grid potential in the form of a combination of the wave generated in 3H and the incoming pulses.
- Circuit 34l is preferably tuned to some harmonic of the cadence frequency of the input pulses so that as the repetition rate is varied, due to the modulation signals, the output pulses will be raised to different levels depending upon their time displacement. Accordingly, in the output of tube 340 will appear a modulation envelope of pulses carrying signal modulations thereon.
- a low-pass filter 345 is provided to remove from this demodulated signal envelope the pulses of higher frequencies that define the signal envelope.
- pulse width selectors of Figs. 2 and 3 may comprise any circuit arrangement capable of segregating a pulse of a given width from pulses of greater and/or lesser widths.
- Fig. 10 for purposes of illustration, a suitable circuit which, depending upon selection of circuit constants, is capable of distinguishing between two pulse widths difiering by as little as one hundredth of a microsecond. Such fine distinction, however, is not necessary except where selection among a very large number of difierent pulse widths are required between close limits.
- the circuit of Fig. 10 preferably includes a limit clipping stage 353 as an input coupler which limits all input pulses to substantially the same amplitude. Should the input pulses be of a positive polarity as indicated by the pulses of curve Ila in Fig. 11, the coupled stage 350 also serves to reverse the polarity as indicated by the pulses of curve I lb.
- This output pulse energy from stage 359 is applied through a resistor R to a shock excitable L-C circuit 355.
- a vacuum tube 360 Connected across the tunable circuit 355 is a vacuum tube 360, the cathode 36l of which is connected to the input side of the circuit 355, while the anode 362 is connected to the opposite side 363 of the tunable circuit.
- the side 363 is also connected to a source of anode potential 364.
- the pulse energy, curve I lb, from the anode connection 354 is applied to the grid 365 of the tube 380 so as to block the conduction between the cathode 36l and the anode 382 while pulse energy is applied to the circuit 355.
- the undulations produced in the circuit 355 in response to pulse energy over anode connection 354 are taken oil through a connection 3'10 for application to a threshold clippin amplifier stage 315.
- the bias on the grid 376 is controlled by adjustment of resistor 311.
- In the output 318 of stage 215 is a pulse width shaper 389, the operation of which is hereinafter described.
- the widths of the pulses of curves Ho and llb correspond, respectively, to channels I, 3, 5, l and 9. as indicated by the width reference characters Wl, W3, W5, W1, and W9.
- the circuit 355 is tuned for selection of pulse width W5.
- Curve I I0 represents the output of the circuit 355 when the circuit 355 is tuned for selection of pulse width W5, illustrating the different output undulations for the difierent pulse widths of curve Ila.
- the trailing edge 386 occurs where the initiated oscillatory energy crosses the zero axis from undulation 382 to undulation 383. Since the trailing edge 386 shock excites the circuit in the same direction at this point, an undulation 381 coinciding substantially with 383 produced thereby in the circuit 355 adds algebraically to the undulation 383 to produce undulation 399. The next succeeding pairs of undulations produced by the leadin and trailing edges of pulse width W5 would normally tend to produce a negative undulation which would continue as a damned wave.
- the damping tube 360 eliminates the trailing oscillations so that they do not interere wit the undulations produced by subsequent nulses a plied to the circuit 355.
- a pulse width less than nulse width W5. such. for example. as pulse widths WI and W3, will -ot pro ce maximum undu ations as great as the undulation 398 for the tuning adjustment corres onding to pulse width W5.
- the reason for this is readily a parent because the shock excitations nroduced bv the leading and trailing edges of the pulses of lesser width than W5 are, in part. opposed to each other. as indicated y the broken lines associated with t e undulations 393 and 394.
- the undulations 395 and 396 produced in re ponse to the greater pulse widths W! and W9 are likewise smaller than the undulation 39! since here again the oscillations produced in response to the leading and trailing edges of the greater
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Priority Applications (11)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
BE477481D BE477481A (US07655688-20100202-C00086.png) | 1944-05-05 | ||
BE482468D BE482468A (US07655688-20100202-C00086.png) | 1944-05-05 | ||
BE474663D BE474663A (US07655688-20100202-C00086.png) | 1944-05-05 | ||
US531851A US2509218A (en) | 1944-04-20 | 1944-04-20 | Repeater link system |
US534284A US2421017A (en) | 1944-05-05 | 1944-05-05 | Communication and guiding system |
GB10724/45A GB604445A (en) | 1944-05-05 | 1945-04-27 | Radio communication and guiding system for mobile units |
US657710A US2471416A (en) | 1944-05-05 | 1946-03-28 | Radio communicating system |
GB7814/47A GB625478A (en) | 1944-05-05 | 1947-03-21 | Improvements in or relating to multichannel radio systems for communication with moving vehicles |
ES0178737A ES178737A1 (es) | 1944-05-05 | 1947-07-02 | Mejoras en sistemas de telecomunicacion y guia |
CH283937D CH283937A (fr) | 1944-05-05 | 1947-08-02 | Installation de communication radioélectrique pour des véhicules. |
CH281168D CH281168A (fr) | 1944-05-05 | 1947-08-27 | Installation de balise radioélectrique pour le guidage de mobiles. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US534284A US2421017A (en) | 1944-05-05 | 1944-05-05 | Communication and guiding system |
Publications (1)
Publication Number | Publication Date |
---|---|
US2421017A true US2421017A (en) | 1947-05-27 |
Family
ID=24129435
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US534284A Expired - Lifetime US2421017A (en) | 1944-04-20 | 1944-05-05 | Communication and guiding system |
Country Status (5)
Cited By (45)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2471416A (en) * | 1944-05-05 | 1949-05-31 | Standard Telephones Cables Ltd | Radio communicating system |
US2477625A (en) * | 1944-08-25 | 1949-08-02 | Standard Telephones Cables Ltd | Multiplex television and pulse modulated sound system |
US2481516A (en) * | 1946-03-22 | 1949-09-13 | Lance R Jacobsen | Mobile telephone system |
US2490061A (en) * | 1947-07-31 | 1949-12-06 | United Air Lines Inc | Radio-wire communication system |
US2502317A (en) * | 1947-09-30 | 1950-03-28 | Rca Corp | Radio navigation |
US2508613A (en) * | 1947-03-19 | 1950-05-23 | Autophon Ag | Arrangement for radio-telephone traffic through exchange between mobile stations andbetween such stations and a telephone network |
US2514436A (en) * | 1948-06-18 | 1950-07-11 | Luis W Alvarez | Airway monitoring and control system |
US2521697A (en) * | 1944-04-29 | 1950-09-12 | Standard Telephones Cables Ltd | Traffic control system |
US2523748A (en) * | 1946-01-29 | 1950-09-26 | Bell Telephone Labor Inc | Carrier telegraph system |
US2523295A (en) * | 1945-06-07 | 1950-09-26 | Farnsworth Res Corp | Airways navigational system |
US2524776A (en) * | 1947-07-02 | 1950-10-10 | Standard Telephones Cables Ltd | Pulse time modulation repeater system |
US2525815A (en) * | 1947-03-20 | 1950-10-17 | Raymond G Lloyd | System of radio aids for aerial navigation |
US2531393A (en) * | 1945-06-08 | 1950-11-28 | Burnight T Robert | Electronic coordinating system |
US2532719A (en) * | 1944-10-16 | 1950-12-05 | John H Homrighous | Dimensional radio communication system |
US2534844A (en) * | 1947-11-26 | 1950-12-19 | Panoramic Radio Corp | Gated triple synchrometric system |
US2535107A (en) * | 1946-04-19 | 1950-12-26 | Panoramic Radio Corp | Navigational system |
US2571386A (en) * | 1949-09-16 | 1951-10-16 | Rca Corp | Early warning relay system |
US2572235A (en) * | 1948-03-30 | 1951-10-23 | Bell Telephone Labor Inc | Multichannel intermodulation interference reduction radio communication system |
US2572725A (en) * | 1946-02-15 | 1951-10-23 | Hazeltine Research Inc | Path-indicating system for mobile craft |
US2579591A (en) * | 1947-04-19 | 1951-12-25 | Westinghouse Electric Corp | Relay system |
US2588930A (en) * | 1947-04-22 | 1952-03-11 | Gen Railway Signal Co | Airway traffic control system |
US2588916A (en) * | 1948-02-02 | 1952-03-11 | Gen Railway Signal Co | Navigational system for airways traffic control |
US2607913A (en) * | 1943-09-15 | 1952-08-19 | Williams Frederic Calland | Radio navigation system |
US2608684A (en) * | 1947-03-29 | 1952-08-26 | Standard Telephones Cables Ltd | Radio navigation system |
US2623208A (en) * | 1947-06-16 | 1952-12-23 | Wallace | Traffic control system |
US2626348A (en) * | 1945-08-08 | 1953-01-20 | Westinghouse Electric Corp | Airborne radio relay and broadcast system |
US2631194A (en) * | 1947-07-22 | 1953-03-10 | Int Standard Electric Corp | Telecommunication system |
US2636166A (en) * | 1947-09-10 | 1953-04-21 | Rca Corp | Bearing deviation indication system |
US2637022A (en) * | 1947-01-16 | 1953-04-28 | Radio Industrie Sa | Communication system between two stations linked by television |
US2642524A (en) * | 1948-11-04 | 1953-06-16 | Gen Electric Co Ltd | Radio communication system |
US2649540A (en) * | 1946-07-08 | 1953-08-18 | John H Homrighous | Multiplex radiophone communication system |
US2665375A (en) * | 1948-09-09 | 1954-01-05 | Gen Electric Co Ltd | Radio telephone system |
US2666198A (en) * | 1948-03-15 | 1954-01-12 | Wallace | Synchrometric radar system |
US2672607A (en) * | 1946-06-10 | 1954-03-16 | Jr James H Mulligan | System for suppressing unwanted recognition signals |
US2678437A (en) * | 1949-04-27 | 1954-05-11 | Gen Railway Signal Co | Air traffic control system |
US2732548A (en) * | 1956-01-24 | Electronic system for correlating | ||
US2781509A (en) * | 1948-11-30 | 1957-02-12 | Rca Corp | Side-lobe rejection circuit for pulse radar system |
US2800651A (en) * | 1948-11-30 | 1957-07-23 | Rca Corp | Radio beacon |
US2831105A (en) * | 1952-04-07 | 1958-04-15 | Louis W Parker | Television distribution system |
US2904674A (en) * | 1956-11-29 | 1959-09-15 | Bell Telephone Labor Inc | Radiant energy highway communication system with controlled directive antenna |
US2918532A (en) * | 1955-02-25 | 1959-12-22 | Itt | Multiplex transmission system |
US2980903A (en) * | 1948-03-19 | 1961-04-18 | Goodyear Aircraft Corp | Radar-command system of time coded pulses |
US3539924A (en) * | 1967-10-12 | 1970-11-10 | Bell Telephone Labor Inc | Zoned mobile radio telephone system |
US5408679A (en) * | 1991-07-18 | 1995-04-18 | Fujitsu Limited | Mobile telecommunications system having an expanded operational zone |
US20130063324A1 (en) * | 2006-12-29 | 2013-03-14 | Broadcom Corporation | Adjustable integrated circuit antenna structure |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2887659A (en) * | 1955-07-26 | 1959-05-19 | Bendix Aviat Corp | Signal network |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2322225A (en) * | 1939-07-29 | 1943-06-22 | Carl J Crane | Aircraft automatic take-off, flight, and landing |
-
0
- BE BE474663D patent/BE474663A/xx unknown
- BE BE477481D patent/BE477481A/xx unknown
- BE BE482468D patent/BE482468A/xx unknown
-
1944
- 1944-05-05 US US534284A patent/US2421017A/en not_active Expired - Lifetime
-
1945
- 1945-04-27 GB GB10724/45A patent/GB604445A/en not_active Expired
-
1947
- 1947-03-21 GB GB7814/47A patent/GB625478A/en not_active Expired
- 1947-07-02 ES ES0178737A patent/ES178737A1/es not_active Expired
- 1947-08-02 CH CH283937D patent/CH283937A/fr unknown
- 1947-08-27 CH CH281168D patent/CH281168A/fr unknown
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2322225A (en) * | 1939-07-29 | 1943-06-22 | Carl J Crane | Aircraft automatic take-off, flight, and landing |
Cited By (46)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2732548A (en) * | 1956-01-24 | Electronic system for correlating | ||
US2607913A (en) * | 1943-09-15 | 1952-08-19 | Williams Frederic Calland | Radio navigation system |
US2521697A (en) * | 1944-04-29 | 1950-09-12 | Standard Telephones Cables Ltd | Traffic control system |
US2471416A (en) * | 1944-05-05 | 1949-05-31 | Standard Telephones Cables Ltd | Radio communicating system |
US2477625A (en) * | 1944-08-25 | 1949-08-02 | Standard Telephones Cables Ltd | Multiplex television and pulse modulated sound system |
US2532719A (en) * | 1944-10-16 | 1950-12-05 | John H Homrighous | Dimensional radio communication system |
US2523295A (en) * | 1945-06-07 | 1950-09-26 | Farnsworth Res Corp | Airways navigational system |
US2531393A (en) * | 1945-06-08 | 1950-11-28 | Burnight T Robert | Electronic coordinating system |
US2626348A (en) * | 1945-08-08 | 1953-01-20 | Westinghouse Electric Corp | Airborne radio relay and broadcast system |
US2523748A (en) * | 1946-01-29 | 1950-09-26 | Bell Telephone Labor Inc | Carrier telegraph system |
US2572725A (en) * | 1946-02-15 | 1951-10-23 | Hazeltine Research Inc | Path-indicating system for mobile craft |
US2481516A (en) * | 1946-03-22 | 1949-09-13 | Lance R Jacobsen | Mobile telephone system |
US2535107A (en) * | 1946-04-19 | 1950-12-26 | Panoramic Radio Corp | Navigational system |
US2672607A (en) * | 1946-06-10 | 1954-03-16 | Jr James H Mulligan | System for suppressing unwanted recognition signals |
US2649540A (en) * | 1946-07-08 | 1953-08-18 | John H Homrighous | Multiplex radiophone communication system |
US2637022A (en) * | 1947-01-16 | 1953-04-28 | Radio Industrie Sa | Communication system between two stations linked by television |
US2508613A (en) * | 1947-03-19 | 1950-05-23 | Autophon Ag | Arrangement for radio-telephone traffic through exchange between mobile stations andbetween such stations and a telephone network |
US2525815A (en) * | 1947-03-20 | 1950-10-17 | Raymond G Lloyd | System of radio aids for aerial navigation |
US2608684A (en) * | 1947-03-29 | 1952-08-26 | Standard Telephones Cables Ltd | Radio navigation system |
US2579591A (en) * | 1947-04-19 | 1951-12-25 | Westinghouse Electric Corp | Relay system |
US2588930A (en) * | 1947-04-22 | 1952-03-11 | Gen Railway Signal Co | Airway traffic control system |
US2623208A (en) * | 1947-06-16 | 1952-12-23 | Wallace | Traffic control system |
US2524776A (en) * | 1947-07-02 | 1950-10-10 | Standard Telephones Cables Ltd | Pulse time modulation repeater system |
US2631194A (en) * | 1947-07-22 | 1953-03-10 | Int Standard Electric Corp | Telecommunication system |
US2490061A (en) * | 1947-07-31 | 1949-12-06 | United Air Lines Inc | Radio-wire communication system |
US2636166A (en) * | 1947-09-10 | 1953-04-21 | Rca Corp | Bearing deviation indication system |
US2502317A (en) * | 1947-09-30 | 1950-03-28 | Rca Corp | Radio navigation |
US2534844A (en) * | 1947-11-26 | 1950-12-19 | Panoramic Radio Corp | Gated triple synchrometric system |
US2588916A (en) * | 1948-02-02 | 1952-03-11 | Gen Railway Signal Co | Navigational system for airways traffic control |
US2666198A (en) * | 1948-03-15 | 1954-01-12 | Wallace | Synchrometric radar system |
US2980903A (en) * | 1948-03-19 | 1961-04-18 | Goodyear Aircraft Corp | Radar-command system of time coded pulses |
US2572235A (en) * | 1948-03-30 | 1951-10-23 | Bell Telephone Labor Inc | Multichannel intermodulation interference reduction radio communication system |
US2514436A (en) * | 1948-06-18 | 1950-07-11 | Luis W Alvarez | Airway monitoring and control system |
US2665375A (en) * | 1948-09-09 | 1954-01-05 | Gen Electric Co Ltd | Radio telephone system |
US2642524A (en) * | 1948-11-04 | 1953-06-16 | Gen Electric Co Ltd | Radio communication system |
US2781509A (en) * | 1948-11-30 | 1957-02-12 | Rca Corp | Side-lobe rejection circuit for pulse radar system |
US2800651A (en) * | 1948-11-30 | 1957-07-23 | Rca Corp | Radio beacon |
US2678437A (en) * | 1949-04-27 | 1954-05-11 | Gen Railway Signal Co | Air traffic control system |
US2571386A (en) * | 1949-09-16 | 1951-10-16 | Rca Corp | Early warning relay system |
US2831105A (en) * | 1952-04-07 | 1958-04-15 | Louis W Parker | Television distribution system |
US2918532A (en) * | 1955-02-25 | 1959-12-22 | Itt | Multiplex transmission system |
US2904674A (en) * | 1956-11-29 | 1959-09-15 | Bell Telephone Labor Inc | Radiant energy highway communication system with controlled directive antenna |
US3539924A (en) * | 1967-10-12 | 1970-11-10 | Bell Telephone Labor Inc | Zoned mobile radio telephone system |
US5408679A (en) * | 1991-07-18 | 1995-04-18 | Fujitsu Limited | Mobile telecommunications system having an expanded operational zone |
US20130063324A1 (en) * | 2006-12-29 | 2013-03-14 | Broadcom Corporation | Adjustable integrated circuit antenna structure |
US8659491B2 (en) * | 2006-12-29 | 2014-02-25 | Broadcom Corporation | Adjustable integrated circuit antenna structure |
Also Published As
Publication number | Publication date |
---|---|
BE477481A (US07655688-20100202-C00086.png) | |
BE482468A (US07655688-20100202-C00086.png) | |
CH283937A (fr) | 1952-06-30 |
CH281168A (fr) | 1952-02-29 |
GB625478A (en) | 1949-06-28 |
ES178737A1 (es) | 1947-09-01 |
BE474663A (US07655688-20100202-C00086.png) | |
GB604445A (en) | 1948-07-05 |
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