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Publication numberUSH481 H
Publication typeGrant
Application numberUS 06/793,811
Publication dateJun 7, 1988
Filing dateNov 1, 1985
Priority dateNov 1, 1985
Publication number06793811, 793811, US H481 H, US H481H, US-H-H481, USH481 H, USH481H
InventorsFrancis X. Filardo, Michael C. Scott
Original AssigneeThe United States Of America As Represented By The Secretary Of The Air Force
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Microprocessor controlled RF modulator apparatus
US H481 H
Abstract
The microprocessor-controlled RF modulator apparatus will provide repeatable, controlled scintillation on a test bench generated low-power RF target waveforms for the purpose of providing a target returns with realistic radar cross section characteristics during testing of the F-16 (or any other) fire control radar. The microprocessor-controlled RF modulator apparatus is utilized in line between an RF target signal generator and the target horn to provide a variety of target situations for testing radar hardware and software.
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Claims(7)
What is claimed is:
1. A microprocessor-controlled RF modulator apparatus for testing a fire control radar comprising in combination:
means for processing digital data which is operated by a four MHz clock means, said processing means utilizing said digital data to generate a digital target return signal,
memory means for storing a predetermined amount of digital data, said memory means being eraseable and programmable, said memory means being operatively connected to said processing means,
input port means for selecting a test target return signal, said input port means operatively connected to said processing means,
means for converting said digital target return signal to a analog target return modulating signal, said converting means being operatively connected to said processing means, and,
means for attenuating operatively connected to said converting means to receive said analog target return modulating signal therefrom, said attenuating means receiving an RF signal, said attenuating means in response to said analog target return modulating signal modulates said RF signal to provide a modulated test target return signal.
2. A microprocessor-controlled RF modulator apparatus as described in claim 1 wherein memory means comprises a 20K EPROM memory unit.
3. A microprocessor-controlled RF modulator apparatus as described in claim 1 wherein said converting means comprises an output latch means operatively connected to said processing means, said output latch means buffering data into and out of said processing means,
a digital to analog converter means operatively connected to said output latch means to receive data therefrom, said digital to analog converter means converting said data to an analog signal, and,
an amplitude control means operatively connected to said digital to analog converter means to receive said analog signal therefrom, said amplitude control means generating control voltage which is applied to said attenuating means to control the output signal therefrom.
4. A microprocessor-controlled RF modulator apparatus as described in claim 1 wherein said attenuating means comprises a PIN diode attenuator.
5. A microprocessor-controlled RF modulator apparatus as described in claim 1 further including an RF target generator to provide an RF signal to said microprocessor-controlled RF modulator apparatus, said test target return signal from said attenuating means being applied to an RF target horn, said RF target horn radiating said test target return signal to a fire control radar which is under test.
6. A microprocessor-controlled RF modulator apparatus as described in claim 2 wherein said 20K EPROM memory unit comprises ten 2K EPROMS with their respective input lines connected in parallel and their respective output lines connected in parallel, both of which lines are respectively connected to said processing means.
7. A microprocessor-controlled RF modulator apparatus as described in claim 6 wherein said converting means comprises an output latch means operatively connected to said processing means, said ouput latch means buffering data into and out of said processing means,
a digital to analog converter means operatively connected to said output latch means to receive data therefrom, said digital to analog converter means converting said data to an analog signal,
an amplitude control means operatively connected to said digital to analog converter means to receive said analog signal therefrom, said amplitude control means generating control voltage which is applied to said attenuating means to control the output signal therefrom, and,
said attenuating means comprises a PIN diode attenuator.
Description
STATEMENT OF GOVERNMENT INTEREST

The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon.

BACKGROUND OF THE INVENTION

The present invention relates broadly to an RF modulator apparatus, and in particular to a microprocessor-controlled RF modulator apparatus.

The state of the art of radar target signal simulators is well represented and alleviated to some degree by the prior arts apparatus and approaches which are contained in the following U.S. Patents:

U.S. Pat. No. 3,571,479 issued to Horattas et al on Mar. 16, 1971;

U.S. Pat. No. 3,783,172 issued to Bernstein on Jan. 1, 1974;

U.S. Pat. No. 3,792,475 issued to Smetana on Mar. 9, 1972;

U.S. Pat. No. 4,168,502 issued to Susie on Mar. 15, 1978;

U.S. Pat. No. 4,224,583 issued to Larken on Nov. 29, 1978; and

U.S. Pat. No. 4,327,417 issued to Zaczek on June 6, 1980.

The early prior art approach to radar target generation or simulation is shown in the prior art patents of Horattas et al and Bernstein. The Horattas et al patent is directed toward a digital electronic target generator wherein digitized radar targets are stored in a memory matrix where range is "bit" oriented and aximuth is "word" oriented. Each word in the matrix represents an azimuth line segment of a target on a radar display and the bit position within a matrix word represents the target range, each bit being the smallest range unit defined by the resolution of the display. A computer identifies the location of all targets in the display matrix and transfers the data to parallel-to-serial shift registers which output serial pulse trains representative of the target words. An output signal having analog characteristics is produced by summing the shift register output results and may be used in a simulator visual display.

The Berstein patent comprises a radar simulator apparatus which utilizes a general-purpose digital computer and a special interface which generates suitable video signals in response to the computer outputs to drive a radar set. In a radar simulator in which several different types of radar targets are simulated, the apparatus of this invention is used to generate the video signals which will display a plurality of mobile targets on the radar set. A limited number of such targets are displayed, and the characteristics of these targets are entered into the computer. Information representing the initial locations of the selected targets and their directions and speeds of movement is inserted into the computer from a remote station, and the computer performs the necessary navigational computations to continually determine the location of the radar set in the gaming area, the bearing of each of the targets from the radar set, and the bearing of the radar antenna at any time. The ranges of all of the targets on a particular bearing are entered by the computer into a register in the order of increasing range from the radar set. When the simulated radar antenna bearing agrees with the target bearing, the stored target ranges are read from the register and are converted into video signals to drive the radar set.

The Smetana, Zaczek and Susie patents respectively illustrate the present day approach of prior art target signal simulators which have been either extremely complicated in that they were controlled by a digital computer or limited to producing signals useful in testing short range or low PRF radar systems. The computer based systems were complicated due to the extensive programming which is required to generate the delays that correspond to the range of the simulated target and to calculate the pulse repetition frequency of the simulated target signal. The limited range of the simulators which did not use digital computers, resulted primarily from the fact that they provided no convenient means for generating a simulated target signal in which the time interval between adjacent pulses of the signal was less than the transit time to and from the simulated target.

The Larkin patent presents another novel approach to the field of radar target signal simulation through the use of a linear attenuator which uses a dc control current to change the RF resistance of PIN diodes that are in series and parallel with the load. As the control current changes, the RF resistance of the series diode will vary inversely, while the RF resistance of the parallel diode will vary directly thereby providing attenuation which changes linearly as a function of the control current through the series diode. The present invention is directed to a microprocessor-controlled RF modulator apparatus which provides RF target return signals to a fire control radar with realistic radar characteristics.

SUMMARY OF THE INVENTION

The present invention utilizes a microprocessor which is controllable in both attenuation range and frequency to amplitude modulate a test bench generated radar target return signal. The radar characteristic of the target are varied with respect to aspect angle, radar cross section and other physical parameter to provide a non-stable, time/amplitude varying signal which is representative of a true radar target.

It is one object of the present invention, therefore, to provide an improved microprocessor-controlled RF modulator apparatus.

It is another object of the invention to provide an improved microprocessor-controlled RF modulator apparatus that will generate repeatable, controlled scintillation to low-power waveforms.

It is another object of the invention to provide an improved microprocessor-controlled RF modulator apparatus with a realistic target simulation since the received target signal is amplitude modulated by the microprocessor unit.

It is another object of the invention to provide an improved microprocessor-controlled RF modulator apparatus which is controllable in both attenuation range and frequency.

It is another object of the invention to provide an improved microprocessor-controlled RF modulator apparatus wherein the degree of modulation can be controlled within minimum and maximum levels.

It is another object of the invention to provide an improved microprocessor-controlled RF modulator apparatus that generates a non-stable varying target return signal which is representative of a true air-to-air target.

These and other advantages, objects and features of the invention will become more apparent after considering the following description taken in conjunction with the illustrative embodiment in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating the use of the microprocessor-controlled RF modulator apparatus in a standard test set-up,

FIG. 2 is a block diagram of the microprocessor-controlled RF modulator apparatus according to the present invention,

FIG. 3 is a graphical representation of a variety of sample modulation waveforms,

FIG. 4 is a schematic diagram of the Z-80 central processor unit,

FIG. 5 is a schematic diagram of the 20K EPROM, memory unit,

FIG. 6 is a schematic diagram of the output latch unit and the digital to analog converter (DAC) unit, and,

FIG. 7 is a schematic diagram of the PIN diode attenuator unit.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning now to FIG. 1 there is shown a block diagram of a standard test set-up utilizing the microprocessor-controlled RF modulator apparatus 10 for testing a fire control radar unit 12. The system test bench unit 14 typically comprises an RF target generator unit 14a, a target controller unit 14b and an avionics simulator panel unit 14c. The test bench generated target signal is applied to the microprocessor-controlled RF modulator apparatus 10 wherein it is amplitude modulated and is controlled in both frequency and attenuation range. The modulated RF target return signal from the microprocessor-controlled RF modulator apparatus 10 is applied to the target horn 16. The target horn 16 is arranged to transmit the modulated RF target return signal to the fire control radar unit 12 which is under test.

The microprocessor-controlled RF modulator apparatus will provide repeatable, controlled scintillation to low-power RF waveforms for the purpose of testing the F-16 or any other fire control radar. The microprocessor-controlled RF modulator apparatus 10 is shown in FIG. 1 as installed in line between an RF target generator unit 14a and a target horn unit 16 to provide many added capabilities for testing the hardware and software of a fire control radar unit. This apparatus provides the user with a most realistic target simulation since the received target signal is amplitude modulated by the Z-80 microprocessor (which is shown in FIG. 2) and is controllable in both attenuation range and frequency. The scintillation (modulation) that can be provided can be square wave, swept square wave, triangle wave, sine wave or repeatable random noise at a number of frequencies and, in the case of the square wave functions, at a number of duty factors. The type of modulation, the frequency of the modulation and the duty factor are selected by setting the mini-lever switches which are respectively labelled Mode, Port 1 and Port 2 on the front panel of the microprocessor-controlled RF modulator apparatus. An operator may also control the degree of modulation by selecting the desired attenuation level with the Attenuation knob on the front panel. The minimum and maximum attenuation levels comprise a range of 0 to 60 db in steps of 0, 3, 10, 20, or 60 db.

A most effective use of the microprocessor-controlled RF modulator apparatus here at the Westinghouse Defense Center is to provide this controlled scintillation to a target signal that is generated by the F-16 system test bench. Now, instead of having the AN/APG-66 Fire Control Radar search, acquire and track a non-varying, non-oscillating, artificial target, the F-16 radar unit which is under test, must now respond to a simulated target signal whose generated aspect angle, radar cross section and physical characteristics are changing in a most realistic way. The amplitude modulation or scintillation, that is applied to the F-16 system test bench-generated RF target signal, provides a non-stable, varying RF target signal return which is a better representation of a true air-to-air target.

The versatility of the microprocessor-controlled modulator apparatus is especially evident in jamming scenarios since the radar no longer has a steady and solid target to detect and track, but instead, has to detect a target signal that is oscillating or modulating in the presence of a threat environment. This type of testing is valuable since, with the use of the microprocessor-controlled RF modulator apparatus, realistic target returns can be processed in the radar in both ECM and non-ECM environments.

Turning now to FIG. 2 there is shown a block diagram of the microprocessor-controlled RF modulator apparatus. Input ports unit 20 is operatively connected to the data select means which is not shown in FIG. 2 but is shown in FIG. 1 as the minilever switches that are labelled, Mode, Port 1 and Port 2. The input ports unit 20 which is connected to the Z-80 microprocessor unit 22 communicates the switch settings that control the output waveform parameters to the Z-80 central processor unit (CPU) 22. The Z-80 CPU unit 22 receives a 4 MHz clock signal from clock unit 26. An EPROM memory unit 24 which is a 20K memory unit is operatively connected to the Z-80 CPU unit 22. The EPROM memory unit 24 stores the waveform data and parameters which are utilized by the Z-80 CPU unit 22 to generate the simulated radar target test signal. The digital data which represents the radar target test signal is applied through output latch unit 28 to the digital to analog (DAC) unit 30 for conversion to an analog signal. The analog signal from the DAC unit 30 is applied to the amplitude control unit 32 which in response thereto generates a control voltage signal. The pin diode attenuator unit 34 utilizes the control voltage signal to modulate and structure the RF in signal into the selected waveform shape which becomes the RF out signal.

The microprocessor-controlled RF modulator apparatus utilizes the Z-80 CPU and its associated hardware and software to control the RF input signal that is received by the PIN diode unit. The PIN diode unit comprises a General Microwave D1958 PIN diode attenuator unit that provides a linear correspondence between a control voltage (0-6 VDC) and attenuation (0-60 dB). This control voltage which is converted to an analog signal by the digital analog converter unit and the amplitude control unit is the product of the microprocessor outputs and/or stored PROM memory data. Typical control voltage waveforms which may be generated by the microprocessor-controlled modulator apparatus are shown in FIG. 3 and are labelled (a) through (h). In Table I below there is shown the switch positions which provide the logic code to the Z-80 CPU to generate the digital signal that represents a particular output waveform.

              TABLE I______________________________________The switch logic positions for the microprocessor-controlled RF modulator apparatus is shown as follows:Mode  Port 1  Port 2  Result______________________________________0     X       X       Not used1     X       X       0 dB Attenuation2     0       X       RANDOM DATA - 125 Hz Switching                 Freq. 1       X       RANDOM DATA - 80 Hz 2       X       RANDOM DATA - 45 Hz 3       X       RANDOM DATA - 20 Hz 4       X       RANDOM DATA - 15 Hz 5       X       RANDOM DATA - 2 Hz 6       X       RANDOM DATA - 1 Hz 7       X       RANDOM DATA - .5 Hz3     0       X       6 Hz SQUARE 1       X       35 Hz SQUARE 2       X       80 Hz SQUARE 3       X       150 Hz SQUARE 4       X       180 Hz SQUARE 5       X       250 Hz SQUARE 6       X       350 Hz SQUARE 7       X       650 Hz SQUARE X       0       97.5% Duty SQUARE X       1       88.0% Duty SQUARE X       2       73.0% Duty SQUARE X       3       50.0% Duty SQUARE X       4       27.0% Duty SQUARE X       5       12.0% Duty SQUARE X       6       2.5% Duty SQUARE4     X       X       28.6-80 Hz SWEPT SQUARE                 in 2 seconds5     0       X       .5 Hz SINE 1       X       2 Hz SINE 2       X       12 Hz SINE 3       X       24 Hz SINE 4       X       28 Hz SINE 5       X       55 Hz SINE 6       X       110 Hz SINE 7       X       220 Hz SINE6     0       X       2 Hz TRIANGLE 1       X       10 Hz TRIANGLE 2       X       20 Hz TRIANGLE 3       X       40 Hz TRIANGLE 4       X       50 Hz TRIANGLE 5       X       83 Hz TRIANGLE 6       X       125 Hz TRIANGLE 7       X       167 Hz TRIANGLE7     X       X       Not used______________________________________ (Note: X indicates that the switch position doesn't matter.)

The microprocessor is an eight-bit, 40-pin device, which is operated by a 4 MHz clock and uses 20K of programmed data that is stored on ten (10) 2K EPROM memory chips. The remainder of the circuitry of the microprocessor-controlled RF modulator apparatus controls the buffering of the address and data lines, the I/O circuitry, and provides the gain and impedence matching which is required to drive the PIN diode attenuator.

In FIGS. 4 through 7, there is shown a complete schematic diagram of the microprocessor-controlled RF modulator apparatus wherein similarly designated points are commonly connected. The parts list for the schematic diagram of FIGS. 4 through 7 is given in Table 2 as follows:

              TABLE 2______________________________________1 -    Z-80 Microprocessor (Zilog)1 -    7406 MED1 -    74145 MED6 -    74244 MED2 -    74243 MED1 -    4 MHz oscillator10 -   2716 EPROMs Intel Corp.,1 -    74100 MED1 -    DAC1 -    PIN Diode Attenuator (Gen. Microwave D1958)3 -    Minilever Switches1 -    7400 MED1 -    3P2T switch1 -    2PlT momentary switch2 -    741 Op-amp MED1 -    5P wafer switch2 -    0-20K trim pots2 -    10K, 1/8 W resistor1 -    400 ohm, 1/8 W resistor1 -    22 ohm, 1/8 W resistor1 -    82 ohm, 1/8 W resistor1 -    220 ohm, 1/8 W resistor23 -   330 ohm, 1/8 W resistor______________________________________

In FIG. 4 there is shown a schematic diagram of the Z-80 microprocessor (CPU) and its associated circuitry. The elements of FIG. 4 can be related to the block diagram of FIG. 2 as follows. The Z-80 CPU of FIG. 2 comprises Z-80 microprocessor unit, the data line buffer units (74243); the address line buffer units (74244); the demultiplexer unit (74145) and its associated resistor array. In FIG. 5 there is shown the 20K EPROM memory unit which comprises ten 2K EPROM units (2716). In FIG. 6 there is shown the input ports unit of FIG. 2 which comprises the three minilever switches (Mode Sel, Port 1 and Port 2), the address line buffer units (74244) and the NAND gates (7400) which are associated with the buffer units. In FIG. 6 there is also shown the output latch unit of FIG. 2 which comprises the output latch unit (74100), the digital to analog converter unit (DAC) and the PIN diode attenuator. In FIG. 7 there is shown the amplitude control unit of FIG. 2 which comprises a pair of operational amplifier units (741) and its associated circuitry that includes a five position wafer switch as shown.

A desirable feature of the present apparatus is its programmability. The entire operation of the microprocessor-controlled RF modulator apparatus can be modified by changing the program of the EPROMs. The hardware does not need to be modified at all. The microprocessor-controlled RF modulator apparatus is rack-mountable and uses +5 V, +15 V and -15 V DC power.

The program memory is mapped as follows:

______________________________________0000H-07FFH  (2K)      Program Executive0800H-08FFH  (1K)      Sine Wave Simulation0C00H-OFFFH  (1K)      Unused1000H-4FFFH  (16K)     Random Noise Simulation______________________________________

                                  TABLE 3__________________________________________________________________________ER LINE ADDR     B1 B2 B3 B4                Z80 ASSEMBLER I.L.S.O.__________________________________________________________________________1                     ;*2                     ; MICROPROCESSOR CONTROLLED RF ATTENUATOR3     0000     00                  NOP4     0001     00                  NOP5     0002     00                  NOP6     0003     00                  NOP7     0004     00                  NOP8     0005     00                  NOP9     0006     00                  NOP10    0007     00                  NOP11    0008     00                  NOP12    0009     00                  NOP13    000A     DB 01       START   IN     A,(1)14    000C     3D                  DEC    A15    000D     CA 34 00            JP     Z,0DB16    0010     3D                  DEC    A17    0011     CA F7 01            JP     Z,SAMPLE18    0014     3D                  DEC    A19    0015     CA 1C 01            JP     A,SQW20    0018     3D                  DEC    A21    0019     CA 83 00            JP     Z,SWP22    001C     3D                  DEC    A23    001D     CA 3B 00            JP     Z,SINE24    0020     3D                  DEC    A25    0021     CA EE 00            JP     Z,TRW26    0024     D3 02       RNDM    IN     A,(2)27    0026     DD 21 67 01         LD     IX,TBL228    002A     21 FF 3F            LD     HL,3FFFH29    002D     FD 21 00 10         LD     IY,1000H30    0031     C3 48 00            JP     S031    0034     3E 00       ODB     LD     A,O32    0036     D3 10               OUT    (10H),A33    0038     C3 0A 00            JP     START34    003B     DB 02       SINE    IN     A,(2)35    003D     DD 21 5F 01         LD     IX,TBL136    0041     21 FF 03            LD     HL,03FFH37    0044     FD 21 00 0B         LD     IY,0900H38    0048     16 00       GO      LD     D,O39    004A     5F                  LD     E,A40    004B     DD 19               ADD    IX,DE41    004D     01 01 00            LD     BC,142    0050     D6 04               SUB    443    0052     FA 50 00    SKIP    JP     M,CEXT44    0055     DD 7E 00            LD     A, IX)45    0058     4F                  LD     C,A146    0059     C3 66 00            JP     OUT47    0050     DD 7E 00    NEXT    LD     A,(IX)48    005F     3D          LOOP    DEC    A49    0060     CA 66 00            JP     Z,OUT50    0063     C3 5F 00            JP     LOOP51    0066     FD 7E 00    OUT     LD     A,(IY + 0)52    0069     D3 10               OUT    (10H),A53    0068     FD 09               ADD    IY,BO54    0060     ED 42               SHC    HL,BC55    006F     FA 79 00            JP     M,CHJZ56    0072     DB 02               IN     A,(2)57    0074     D6 04               SUB    458    0076     C3 52 00            JP     SKIP59    0079     DB 01       CHUZ    IN     A,(1)60    0078     D6 05               SUB    561    0070     CA 3B 00            JP     Z,SINE62    0080     C3 24 00            JP     RNDM63    0083     01 00 00    SWP     LD     BC,O64    0086     3E FF       SWL2    LD     A,OFFH65    0088     D3 10               OUT    (10H),A66    008A     11 FF FF            LD     DE,-167    008D     21 20 04            LD     HL,105BD68    0090     09                  ADD    HL,BC69    0091     19          SWL     ADD    HL,DE70    0092     38 FD               JP     C,SWL71    0094     00                  NOP72    0095     00                  NOP73    0096     00                  NOP74    0097     00                  NOP75    0098     00                  NOP76    0099     00                  NOP77    009A     00                  NOP78    009B     00                  NOP79    009C     00                  NOP80    009D     00                  NOP81    009E     00                  NOP82    009F     00                  NOP83    00A0     00                  NOP84    00A1     00                  NOP85    00A2     00                  NOP86    00A3     00                  NOP87    00A4     00                  NOP88    00A5     00                  NOP89    00A6     00                  NOP90    00A7     00                  NOP91    00A8     00                  NOP92    00A9     00                  NOP93    00AA     00                  NOP94    00AB     00                  NOP95    00AC     00                  NOP96    00AD     00                  NOP97    00AE     00                  NOP98    00AF     00                  NOP99    00B0     00                  NOP100   00B1     00                  NOP101   00B2     00                  NOP102   00B3     00                  NOP103   00B4     00                  NOP104   00B5     00                  NOP105   00B6     00                  NOP106   00B7     00                  NOP107   00B8     00                  NOP108   00B9     00                  NOP109   00BA     00                  NOP110   00BB     00                  NOP111   00BC     00                  NOP112   00BD     00                  NOP113   00BE     00                  NOP114   00BF     00                  NOP115   00C0     3E 00               LD     A,116   00C2     D3 10               OUT    (10H),A117   00C4     11 FF FF            LD     DE,-1118   00C7     21 20 04            LD     HL,1056D119   00CA     09                  ADD    HL,BC120   00CB     19          SWL1    ADD    HL,DE121   00CC     38 FD               JR     C,SWL1122   00CE     0B                  DEC    BC123   00CF     0B                  DEC    BC124   00D0     0B                  DEC    BC125   00D1     0B                  DEC    BC126   00D2     0B                  DEC    BC127   00D3     0B                  DEC    BC128   00D4     0B                  DEC    BC129   00D5     0B                  DEC    BC130   00D6     0B                  DEC    BC131   00D7     0B                  DEC    BC132   00D8     0B                  DEC    BC133   00D9     0B                  DEC    BC134   00DA     0B                  DEC    BC135   00DB     0B                  DEC    BC136   00DC     0B                  DEC    BC137   00DD     0B                  DEC    BC138   00DE     0B                  DEC    BC139   00DF     0B                  DEC    BC140   00E0     0B                  DEC    BC141   00E1     0B                  DEC    BC142   00E2     0B                  DEC    BC143   00E3     0B                  DEC    BC144   00E4     0B                  DEC    BC145   00E5     0B                  DEC    BC146   00E6     0B                  DEC    BC147   00E7     0B                  DEC    BC148   00E8     78                  LD     A,3149   00E9     E6 07               AND    07150   00EB     47                  LD     B,A151   00EC     18 98               JP     SWL2152   00EE     DB 02       TRW     IN     A,(2)153   00F0     57                  LD     D,A154   00F1     06 00               LD     B,O155   00F3     4F                  LD     C,A156   00F4     DD 21 6F 01         LD     IX,TBL3157   00F8     DD 09               ADD    IX,BC158   00FA     DD 46 00            LD     B,(IX + 0)159   00FD     DB 02       TL4     IN     A,(2)160   00FF     BA                  CP     D161   0100     20 EC               JR     NZ,TRW162   0102     3E 00               LD     A,0163   0104     D3 10       TL3     OUT    (10H),A164   0106     3C                  INC    A165   0107     28 06               JR     Z,TL1166   0109     48                  LD     C,B167   010A     0D          TL2     DEC    C168   010B     20 FD               JR     NZ,TL2169   010D     18 F5               JR     TL3170   010F     3E FF       TL1     LD     A,OFFH171   0111     D3 10       TL6     OUT    (10H),A172   0113     3D                  DEC    A173   0114     28 E7               JR     Z,TL4174   0116     48                  LD     C,B175   0117     OD          TLS     DEC    C176   0118     20 FD               JR     NZ,TL5177   011A     18 F5               JR     TL6178   011C     DB 04       SQW     IN     A,(4)179   011E     E6 07               AND    007H180   0120     4F                  LD     C,A181   0121     DB 02               IN     A,(2)182   0123     E6 07               AND    007H183   0125     CB 27               SLA    A184   0127     CB 27               SLA    A185   0129     CB 27               SLA    A186   012B     81                  ADD    A,C187   0120     CB 27               SLA    A188   012E     06 00               LD     B,O189   0130     4F                  LD     C,A190   0131     DD 21 77 01         LD     IX,TBL4191   0135     DD 09               ADD    IX,BC192   0137     DD 56 00            LD     D,(IX + 0)193   013A     DD 5E 01            LD     E,(IX + 1)194   013D     DB 02               IN     A,(2)195   013F     47                  LD     B,A196   0140     3E 00       SL5     LD     A,O197   0142     D3 10               OUT    (10H),A198   0144     7A                  LD     A,D199   0145     4A          SL2     LD     C,D200   0146     OD          SL1     DEC    C201   0147     20 FD               JR     NZ,SL1202   0149     3D                  DEC    A203   014A     20 F9               JR     NZ,SL2204   014C     DB 02               IN     A,(2)205   014E     B8                  CP     B206   014F     20 CB               JR     NZ,SQW207   0151     3E FF               LD     A,OFFH208   0153     D3 10               OUT    (10H),A209   0155     7B                  LD     A,E210   0156     4B          SL4     LD     C,E211   0157     0D          SL3     DEC    C212   0158     20 FD               JR     NZ,SL3213   015A     3D                  DEC    A214   015B     20 F9               JR     NZ,SL4215   015D     18 E1               JR     SL5216   015F     FF          TRL1    DEFB   OFFH217   0160     4C                  DEFB   04CH218   0161     09                  DEFB   9H219   0162     02                  DEFB   2H220   0163     01                  DEFB   1221   0164     02                  DEFB   2222   0165     04                  DEFB   4223   0166     08                  DEFB   8224   0167     08          TBL2    DEFB   8225   0168     04                  DEFB   4226   0169     02                  DEFB   2227   016A     01                  DEFB   1228   016B     01                  DEFB   1229   016C     02                  DEFB   2230   016D     04                  DEFB   4231   016E     08                  DEFB   3232   016F     00          TBL3    DEFB   0233   0170     2E                  DEFB   46D234   0171     16                  DEFB   22D235   0172     0E                  DEFB   14D236   0173     08                  DEFB   3D237   0174     04                  DEFB   4D238   0175     02                  DEFB   2D239   0176     01                  DEFB   1D240   0177     21          TBL4    DEFB   33D241   0178     E1                  DEFB   225D242   0179     41                  DEFB   65D243   017A     C1                  DEFB   193D244   017B     61                  DEFB   97D245   017C     A1                  DEFB   1610246   017D     B1                  DEFB   129D247   017E     B1                  DEFB   129D248   017F     A1                  DEFB   161D249   0180     61                  DEFB   97D250   0181     C1                  DEFB   193D251   0182     41                  DEFB   65D252   0183     E0                  DEFB   224D253   0184     20                  DEFB   32D254   0185     00                  DEFB   0D255   0186     01                  DEFB   1D256   0187     0E                  DEFB   14D257   0188     62                  DEFB   98D258   0189     1C                  DEFB   28D259   018A     54                  DEFB   84D260   018B     2A                  DEFB   42D261   018C     46                  DEFB   70D262   018D     38                  DEFB   56D263   018E     38                  DEFB   56D264   018F     46                  DEFB   70D265   0190     2A                  DEFB   42D266   0191     54                  DEFB   84D267   0192     1C                  DEFB   28D268   0193     62                  DEFB   98D269   0194     0E                  DEFB   14D270   0195     70                  DEFB   112D271   0196     01                  DEFB   1D272   0197     09                  DEFB   9D273   0198     3E                  DEFB   62D274   0199     12                  DEFB   18D275   019A     35                  DEFB   53D276   019B     1B                  DEFB   27D277   019C     2C                  DEFB   44D278   019D     24                  DEFB   36D279   019E     24                  DEFB   36D280   019F     2C                  DEFB   44D281   01A0     1B                  DEFB   27D282   01A1     35                  DEFB   53D283   01A2     12                  DEFB   18D284   01A3     3E                  DEFB   62D285   01A4     09                  DEFB   9D286   01A5     47                  DEFB   71D287   01A6     01                  DEFB   1D288   01A7     07                  DEFB   7D289   01A8     2E                  DEFB   46D290   01A9     0E                  DEFB   14D291   01AA     28                  DEFB   40D292   01AB     14                  DEFB   20D293   01AC     21                  DEFB   33D294   01AD     18                  DEFB   27D295   01AE     18                  DEFB   27D296   01AF     20                  DEFB   32D297   01B0     14                  DEFB   20D298   01B1     28                  DEFB   40D299   01B2     0E                  DEFB   14D300   01B3     2E                  DEFB   46D301   01B4     07                  DEFB   7D302   01B5     35                  DEFB   53D303   01B6     01                  DEFB   1D304   01B7     07                  DEFB   7D305   01B8     2C                  DEFB   44D306   01B9     0D                  DEFB   13307   01BA     25                  DEFB   37308   01BB     13                  DEFB   19D309   01BC     1F                  DEFB   31D310   01BD     19                  DEFB   25D311   01BE     19                  DEFB   25D312   01BF     1F                  DEFB   31D313   01C0     13                  DEFB   19D314   01C1     35                  DEFB   37D315   01C2     0D                  DEFB   13D316   01C3     2B                  DEFB   43D317   01C4     07                  DEFB   7D318   01C5     32                  DEFB   50D319   01C6     01                  DEFB   1D320   01C7     06                  DEFB   6D321   01C8     24                  DEFB   36D322   01C9     0B                  DEFB   11D323   01CA     1F                  DEFB   31D324   01CB     10                  DEFB   16D325   01CC     1A                  DEFB   26D326   01CD     15                  DEFB   21D327   01CE     15                  DEFB   21D328   01CF     1A                  DEFB   26D329   01D0     10                  DEFB   16D330   01D1     1F                  DEFB   31D331   01D2     DB                  DEFB   11D332   01D3     24                  DEFB   36D333   01D4     06                  DEFB   6D334   01D5     29                  DEFB   41D335   01D6     01                  DEFB   1D336   01D7     05                  DEFB   5D337   01D8     1F                  DEFB   31D338   01D9     09                  DEFB   9D339   01DA     1A                  DEFB   26D340   01DB     0D                  DEFB   13D341   01DC     16                  DEFB   22D342   01DD     12                  DEFB   18D343   01DE     12                  DEFB   18D344   01DF     16                  DEFB   22D345   01EO     0D                  DEFB   13D346   01E1     1A                  DEFB   26D347   01E2     09                  DEFB   9D348   01E3     1E                  DEFB   30D349   01E4     05                  DEFB   5D350   01E5     23                  DEFB   35D351   01E6     01                  DEFB   1D352   01E7     04                  DEFB   4D353   01E3     16                  DEFB   22D354   01E9     07                  DEFB   7D355   01EA     13                  DEFB   19D356   01EB     0A                  DEFB   10D357   01EC     10                  DEFB   16D358   01ED     0D                  DEFB   13D359   01EE     0D                  DEFB   13D360   01EF     10                  DEFB   160361   01F0     0A                  DEFB   10D362   01F1     13                  DEFB   19D363   01F2     07                  DEFB   7D364   01F3     16                  DEFB   22D365   01F4     04                  DEFB   4D366   01F5     19                  DEFB   25D367   01F6     01                  DEFB   1D368   01F7     FD 21 00 10 SAMPLE  LD     IY,1000H369   01F8     21 FF 3F            LD     HL,3FFFH370   01FE     FD 46 00            LD     B,(IY)371   0201     DD 21 00 FF SCF     LD     IX,OFF00H372   0205     FD 23               INC    IY373   0207     2B                  DEC    HL374   0208     31 00 00            LD     SP,0375   020B     ED 7A               ADC    HL,SP376   020D     CA F7 01            JP     Z,SAMPLE377   0210     31 01 00            LD     SP,1378   0213     FD 7E 00            LD     A,(IY)433   0275     3D          JJ      DEC    A434   0276     C2 75 02            JP     NZ,JJ435   0279     DB 02               IN     A,(2)436   027B     3D                  DEC    A437   027C     3D                  DEC    A438   027D     3D                  DEC    A439   027E     3D                  DEC    A440   027F     3D                  DEC    A441   0280     CA BE 02            JP     Z,NOUT442   0283     3E FF               LD     A,FFH443   0285     3D          FF      DEC    A444   0286     C2 85 02            JP     NZ,FF445   0289     3E FF               LD     A,OFFH446   028B     3D          KK      DEC    A447   028C     C2 8B 02            JP     NZ,KK448   028F     3E 2C               LD     A,2CH449   0291     3D          LL      DEC    A450   0292     C2 91 02            JP     NZ,LL451   0295     DB 02               IN     A,(2)452   0297     3D                  DEC    A453   0298     3D                  DEC    A454   0299     3D                  DEC    A455   029A     3D                  DEC    A456   029B     3D                  DEC    A457   029C     3D                  DEC    A458   029D     CA BE 02            JP     Z,NOUT459   02A0     3E FF               LD     A, FFH460   02A2     3D          GG      DEC    A461   02A3     C2 A2 02            JP     NZ IGG462   02A6     3E FF               LD     A, FFH463   02A8     3D          HH      DEC    A464   02A9     C2 AB 02            JP     NZ HH465   02AC     3E FF       LD      A,OFFH466   02AE     3D          NN      DEC    A467   02AF     C2 AE 02            JP     NZ,NN468   02B2     3E FF               LD     A,OFFH469   02B4     3D          PP      DEC    A470   02B5     C2 B4 02            JP     NZ PP471   02B8     3E 5E               LD     A, EH472   02BA     3D          QQ      DEC    A473   02BB     C2 BA 02            JP     NZ, QQ474   02BE     78          NOUT    LD     A,B475   02BF     D3 10               OUT    (10H),A476   02C1     DD 39               ADD    IX,SP477   02C3     DA 01 02            JP     C,GOZ478   02C6     C3 23 02            JP     ADD479   02C9     ED 44       NEG     NEG480   02CB     CB 20               SLA    B481   02CD     0E 00               LD     C,O482   02CF     5F                  LD     E,A483   02D0     78          ADDNEG  LD     A,E484   02D1     81                  ADD    A,C485   02D2     D2 D6 02            JP     NC,NBYNEG486   02D5     05                  DEC    B487   02D6     4F          NBYNEG  LD     C,A488   02D7     00                  NOP489   02D8     D2 DC 02            JP     NC,NCYNEG490   02DB     05                  DEC    B491   02DC     4F          NCYNEG  LD     C,A492   02DD     DB 02       LOOPNG  IN     A,(2)493   02DF     3C                  INC    A494   02E0     3D                  DEC    A495   02E1     CA 6B 03            JP     Z,NEGOUT496   02E4     3E 03               LD     A,3H497   02E6     3D          AAA     DEC    A498   02E7     C2 E6 02            JP     NZ,AAA499   02EA     DB 02               IN     A,(2)500   02EC     3D                  DEC    A501   02ED     CA 68 03            JP     A,NEGOUT502   02F0     3E 08               LD     A,BH503   02F2     3D          BBB     DEC    A504   02F3     C2 F2 02            JP     NZ,BBB505   02F6     DB 02               IN     A,(2)506   02F8     3D                  DEC    A507   02F9     3D                  DEC    A508   02FA     CA 68 03            JP     Z,NEGOUT509   02FD     3E 14               LD     A,14H510   02FF     3D          CCC     DEC    A511   0300     C2 FF 02            JP     NZ,CCC512   0303     DB 02               IN     A,(2)513   0305     3D                  DEC    A514   0306     3D                  DEC    A515   0307     3D                  DEC    A516   0308     CA 6B 03            JP     A,NEGOUT517   030B     3E 2D               LD     A,2DH518   030D     3D          DDD     DEC    A519   030E     C2 0D 0D            JP     NZ,DDD520   0311     DB 02               IN     A,(2)521   0313     3D                  DEC    A522   0314     3D                  DEC    A523   0315     3D                  DEC    A524   0316     3D                  DEC    A525   0317     CA 6B 03            JP     Z,NEGOUT526   031A     3E FF               LD     A,OFFH527   031C     3D          EEE     DEC    A528   031D     C2 1C 03            JP     NZ,EEE529   0320     3E CE               LD     A,OCEH530   0322     3D          JJJ     DEC    A531   0323     C2 22 03            JP     NZ,JJJ532   0326     DB 02               IN     A,(2)533   0328     3D                  DEC    A534   0329     3D                  DEC    A535   032A     3D                  DEC    A536   032B     3D                  DEC    A537   032C     3D                  DEC    A538   032D     CA 6B 03            JP     Z,NEGOUT539   0330     3E FF               LD     A,OFFH540   0332     3D          FFF     DEC    A541   0333     C2 32 03            JP     NZ,FFF542   0336     3E FF               LD     A,OFFH543   0338     3D          KKK     DEC    A544   0339     C2 38 03            JP     NZ,KKK545   033C     3E 2C               LD     A,2CH546   033E     3D          LLL     DEC    A547   033F     C2 3E 03            JP     NZ,LLL548   0342     DB 02               IN     A,(2)549   0344     3D                  DEC    A550   0345     3D                  DEC    A551   0346     3D                  DEC    A552   0347     3D                  DEC    A553   0348     3D                  DEC    A554   0349     3D                  DEC    A555   034A     CA 6B 03            JP     A,NEGOUT556   034D     3E FF               LD     A,OFFH557   034F     3D          GGG     DEC    A558   0350     C2 4F 03            JP     NZ,GGG559   0353     3E FF               LD     A,OFFH560   0355     3D          HHH     DEC    A561   0356     C2 55 03            JP     NZ,HHH562   0359     3E FF               LD     A,OFFH563   035B     3D          NNN     DEC    A564   0350     C2 5B 03            JP     NZ,NNN565   035F     3E FF               LD     A,OFFH566   0361     3D          PPP     DEC    A567   0362     C2 61 03            JP     NZ,PPP568   0365     3E 5E               LD     A,5EH569   0367     3D          QQQ     DEC    A570   0368     C2 67 03            JP     NZ,QQQ571   036B     78          NEGOUT  LD     A,B572   036C     D3 10               OUT    (10H),A573   036E     DD 39               ADD    IX,SP574   0370     DA 01 02            JP     C,GOZ575   0373     C3 D0 02            JP     ADDNEG576   0376                    END__________________________________________________________________________ASSEMBLER ERRORS = 0K/WESTINGHOUSE Z80 ASSEMBLER EC-02 VER. DATE 10/5/83 TIME OFF 15CROSS REFERENCELABEL                   VALUE        REFERENCE__________________________________________________________________________AA                      0239         -400AAA                     02E6         -497ADD                     0223         -386ADDNEG                  0200         -483BB                      0245         -406BBB                     02F2         -503CC                      0252         -413CCC                     02FF         -510CHUZ                    0079         -59DD                      0260         -421DDD                     030D         -513EE                      026F         -430EEE                     031C         -527FF                      0285         -443FFF                     0332         -540GG                      02A2         -460GGG                     034F         -557GO                      0048         -33GOZ                     0201         -371H                       02A8         -463HHH                     0355         -560JJ                      0275         -433JJJ                     0322         -530KK                      0288         -446KKK                     0338         -543LL                      0291         -449LLL                     033E         -546LOOP                    005F         -43LOOPNG                  02DD         -492LOOPZ                   0230         -395MEMORY        M         0000         0NBARRY                  0229         -390NBYNEG                  02D6         -487NCARRY                  022F         -394NCYNEG                  02DC         -491NEG                     0209         -479NEGOUT                  036B         -571NEXT                    005C         -47NN                      02AE         -466NNN                     035B         -563NOUT                    02BE         -474ODB                     0034         -31OUT                     0066         -51POS                     021E         -383PP                      0284         -469PPP                     0361         -566QQ                      02BA         -472QQQ                     0367         -569RNDM                    0024         -26SAMPLE                  01F7         -363SINE                    0038         -34SKIP                    0052         -43SL1                     0146         -200SL2                     0145         -199SL3                     0157         -211SL4                     0156         -210SL5                     0140         -196SOW                     011C         - 178STACK         S         0000         0START                   000A         -13SWL                     0091         -69SWL1                    00CB         -120SWL2                    0086         -64SWP                     0083         -63TBL1                    015F         -216TBL2                    0167         -224TBL3                    016F         -232TBL4                    0177         -240TL1                     010F         -170TL2                     010A         -167TL3                     0104         -163TL4                     00FD         -159TL5                     0117         -175TL6                     0111         -171TRW                     00EE         -152__________________________________________________________________________

Other important areas in which the microprocessor-controlled RF modulator apparatus may be used are in developing NCTR algorithms and sideband/sidelobe track processing. Any periodic waveform that can be represented by a series of points (typically 1K or 2K of discrete quanta levels) can be accessed, read and used to modulate a testbench-generated target return. Engine sideband data, NCTR (Non-conforming target recognition) data and any irregular X-band returns of any type can be simulated easily, using existing hardware, with all modifications reserved to the executive algorithm and/or tables of programmed software.

Although the invention has been described with reference to a particular embodiment, it will be understood to those skilled in the art that the invention is capable of a variety of alternative embodiments within the spirit and scope of the appended claims.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US6075480 *Oct 23, 1998Jun 13, 2000Deliberis, Jr.; Romeo A.Down range returns simulator
US8744366 *Sep 26, 2008Jun 3, 2014Richard K. SteenDigitally programmable circuit for controlling an attenuator
Classifications
U.S. Classification342/170, 434/2
International ClassificationG01S7/40
Cooperative ClassificationG01S2007/4082, G01S7/4052
European ClassificationG01S7/40R
Legal Events
DateCodeEventDescription
Nov 13, 1986ASAssignment
Owner name: UNITED STATES OF AMERICA, AS REPRESENTED BY THE SE
Free format text: ASSIGNS THE ENTIRE INTEREST SUBJECT TO LICENSE RECITED;ASSIGNORS:FILARDO, FRANCIS X.;SCOTT, MICHAELC.;REEL/FRAME:004631/0579
Effective date: 19850924