Randle C. Sink Apps
ECM J/S ratio (SSJ) 1.0
For Electronic Counter Measures (ECM), this app is used todetermine the jammer-to-signal (J/S) ratio. For a tracking radar,enter the power in kW, antenna gain in dB, and IF bandwidth in MHz.Then enter the aircraft cross sectional area in m^2 and the rangein km, for a self-screening jammer on board with transmitter powerin kW over a bandwidth in MHz and given antenna gain in dB at adistance from the radar in km For example, Enter Pt = 100, Gr = 35,Br = 1, A = 4, R = 3, Pj = 1, Bj = 20 and Gj = 10. Your values forJ/S (SSJ) should be 16.5.
Microwave Skin Depth 1.0
At microwave frequencies, use the app todetermine the skin depths of aluminum (Al), copper (Cu), gold (Au)or silver (Ag) and others. Use the checkboxes next to the metal toselect it, then enter the frequency (in GHz, that is 10E9), thenpush the "Calculate" button.For f = 10 your results should be 8.15E-7 for Al, 6.6E-7 for Cu,7.86E-7 for Au and 6.41E-7 for Ag.
NTSC S/N Ratio 1.0
For a standard NTSC satellite signal enterbaseband video bandwidth (BBV BW) in MHz, the the RF bandwidth (RFBW) of the signal transmitted over the satellite link in MHz, thereceiving earth station C/N ratio in dB, the de-emphasis value Pand the subjective improvement factor. Carson's rule is used tofind the peak frequency and the baseband S/N ratio appears afterthe "Calculate" button is pushed.As an example, input BBV BW, = 4.2, RF BW = 30, C/N = 15, P= 9& Q= 8 and your output S/N should equal 50.54
Radar Range Equation 1.0
This app is for finding maximum range fordetecting a target using the Radar Range Equation for a pulsedradar when the user enters the operating frequency of the radar inGHz, the antenna gain in dB, the transmitter power in kW (pulsepower), the target cross section area in m^2 and the minimumdetectable signal Pmin in dBm.As an example, enter 10, 28, 2, 12 and -90. The "Calculate"should yield 8113.5 as the maximum range.
ECM J/S ratio (SOJ) 1.0
For ECM, this app is to calculate the J/S ratio for the stand-offjammer (SOJ) situation. In this case, the jammer is at a differentlocation than the target. While the target is in the main beam ofthe radar antenna, the jammer radiates power into the sidelobes. Asan example, for a tracking radar, enter the power in kW antennagain in dB, and IF bandwidth in MHz. Then enter the aircraft crosssectional area in m^2 and the range in km. Next, for a jammer onboard with transmitter power in kW over a bandwidth in MHz andgiven antenna gain in dB at a distance from the radar in km and asidelobe in dB level for the radar antenna. For example, Enter Pt =100, Gr = 35, Br = 1, A = 4, R = 3, Pj = 1, Bj = 20, Gj = 10, Rj =10, & SL = 20. Your value for J/S (SOJ) should be -14.0 dB.
Inverse Chebyshev LP Filter 1.0
This app is used to determine the ripplefactor(e) and the order (n) of the inverse Chebyshev response whentheuser enters the maximum passband attenuation (Wp) in rad/s,thecutoff frequency (Wc), the maximum passband attenuation indB(Amax) and for frequencies greater than or equal thecutofffrequency the minimum response attenuation in db (Amin). Thisapprelieves the user of having to take square roots, divide andraisepowers and take acosh values. As an example, enter Amax = 0.1,Amin= 60, Wp = 250 & Wc = 2000, press the Calculate button andtheoutput should be e = 0.001 and n = 3.424. Otherwise you wouldneedto take Amin, divide by 10, raise that quantity to the 10thpower,then subtract 1 and take the inverse square root just to gete. Toget n you would need to determine acosh values...what adrag!
Basic Plane Wave Parameters 1.0
User enters frequency in GHz, Er &Ur,pushes the "Calculate" button and this app calculatesphasevelocity, wavelength and impedance. As an example, enter 3 forGHz,7 for Er and 3 for Ur, then push calculate. This should resultin6.547E7 m/sec for the phase velocity, 0.0218 m for thewavelengthand 246.9 Ohms for the impedance.
Equivalent Noise Temperature 1.0
To determine the noise figure (NF) of adeviceuse the relationship NF= (S/N)in/(S/N)out. Then in order tofindthe noise temperature use Td = To*(NF - 1) where To isthereference temperature (usually 290 K). The noise figure NF isgivenin dB but this app converts it to a linear ratio.As an example, enter To = 290, NF = 2.5, push "Calculate"andyour result should be Td = 225.7.
Chebyshev Filter app 1.0
This app prompts the user the user forAmax(p-p maximum variation in the pass band) in dB, Amin(minimumresponse attenuation), Wc (upper edge of the pass band) inrad/secand Ws (upper edge of stop band). After hitting theCalculatebutton, the values for Epsilon, e, and the Order of thefilter, n,are returned. For example, enter 0.1 for Amax, 60 forAmin, 250 forWc and 2000 for Ws, hit "Calculate" and your resultsshould beEpsilon e = 0.15262 and Order n = 3.42.Compare this with the Butterworth filter...
Flux Density & Received Power 1.0
This app prompts the user to enter thedistancefrom the satellite to earth in km, the radiated power fromthesatellite in Watts and the gain in dB in the direction oftheobserver and the effective area of the receiving antenna.Onceentered, push the "Calculate" button and the output is F, thefluxdensity in W/m^2, the power received Pr in Watts as well astheflux density in dB and the received power in dBW.For example, enter 40,000 for the distance, 10 for the powerofthe sending antenna and 17 for the gain, then 10 for theeffectivearea of the receiving antenna, push "Calculate" and yourresultsshould be 2.49E-14 W/m^2, 2.49E-13 Watts, -136.03 dB(W/m^2)and-126.03 dBW.
Earth Antenna Received Power 1.0
Knowing the gain (Gr in dB) of thereceivingantenna, the distance from the satellite to the receivingantennaon earth (Km), the frequency that the satellite operates at(GHz),the radiated power of the satellite (in Watts) and the gainof thesatellite antenna (dB) this app will return the EIRP (dBW),pathloss (dB) and the received power of the earth station antenna.To test this, use d = 40000, Pt = 10, Gt = 17, Gr = 52.3 and f=11, "Calculate" should yield EIRP = 27.0, Path loss = -205.3andthe received power Pr = -126.0.
System Noise Temperature 1.0
This is the noise model of a receiving antenna, where all of thenoisy units have been replaced by one noiseless amplifier with asingle noise source Ts as its input. Calculate the system noisetemperature Ts after entering Tin (noise temperature of theantenna), Trf (noise temp. of RF amplifier), Tif (noise temp. of IFamp), Tm (noise temp. of mixer...all in deg. K), then Grf & Gm(gains of RF amp and mixer, both in dB). As the first example, useTin = 25, Trf = 50, Tif = 1000, Tm = 500, Grf = 23 & Gm = 0.Press the "Calculate" button and your result should be 82.5 K. Forexample 2 change Gm to -10 and the result should be 127.5.
Astable 555 Timer 1.0
Adding a second resistor Rb to the 555timerand connecting the trigger input to the threshold input causesthetimer to self-trigger and run as a multivibrator. The capacitorCwill charge through Ra & Rb and discharge through Rb only.Theduty cycle can be controlled by changing the values of Ra andRb.Input Ra, Rb (in kOhms) & C (in uFarads) then pushtheCalculate button to get the values for the outputhigh-levelduration tH and low-level duration tL and frequency.Output driverand output waveform duty cycles are alsodetermined.
