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... power,reliable, low power supply, lowcostBARITT Local oscillators in communicationand radar receiversLow power supply, low cost, lownoise, reliableFigure 1.3 Microwave devices.Figure 1.4 ... devices are employed mainly in the RF region and in low-power microwave circuits, such as low-power transmitters for LAN, and receivercircuits. Some of the applications of solid-state devices ... 2 provides an overview of wireless communication systems andtheir characteristics.8INTRODUCTIONTABLE 1.4 Selected Applications of Microwave Solid-State DevicesDevices Applications AdvantagesTransistors...
... These low- and medium-altitude satellites arevisible from a ground station only for short periods. On the other hand, a satelliteplaced at an altitude of about 36,000 km over the equator is visible ... 2:5:26This constitutes the noise ¯oor of the receiver. A signal weaker than this will be lostin noise. Nocan be expressed in dBW as follows:NodBW10 log10kToFdB10 log10BGdB2:5:27Figure ... antennas and the aperture-typeantennas. Electric dipole, monopole, and loop antennas belong to the former groupwhereas horn, re¯ector, and lens belong to the latter category. The aperture antennascan...
... the input terminals of the load, the location of the ®rst minimumis determined as follows. An arbitrary minimum is located on the slotted line withunknown load. The load is then replaced by a ... from theload, (e) the location of Vmaxand Vminwith respect to load if the line is 0.6 llong, and (f) Zinat the input end.21. A lossless 50-O line is terminated by 25 À j60 O load. Find ... order to understand the behavior of the propagating signal. This isfollowed by the concepts of sending end impedance, re¯ection coef®cient, returnloss, and insertion loss. A quarter-wave impedance...
... frequencies from a wide signal spectrum. Resonant circuits provide such®ltering. There are well-developed,sophisticated methodologies to meet virtuallyany speci®cation. However,a simple circuit suf®ces ... frequency,unloaded Q,and loaded Q of the following parallelresonant circuit.8. The parallel R-L-C circuit shown below is resonant at 20,000 radian=s. If itsadmittance has a magnitude of 1 mS ... practice. In the case of cavitywalls having a ®nite conductivity (instead of in®nite for the perfect conductor) but®lled with a perfect dielectric (no dielectric loss) then its quality factor...
... design frequency.Plot (a) in Figure 5.6 corresponds to design A (that requires a shorter stub closerto the load) while plot (b) represents design B (a longer stub and away from theload). At the ... 150 j15-O loadusing a shunt-connected double-stub tuner. Separation between the two stubs isl=8 and its characteristic impedance is 75 ohm. The stub closest to the load (®rststub) is l=2 ... ®rst stub (load sidestub) must be less than 2 otherwise it cannot be matched.The graphical procedure requires the following steps to ®nd stub settings.1.ZL100 j5050 2 j1.2. Locate...
... impedance transformer is convenientlydeveloped via the power loss ratio, PLR, de®ned as follows:PLR Power loss ratio Incident powerPower delivered to the load1G.L. Matthaei, L. Young, and ... Figure 6.5 shows ®ve minor lobes between twomain peaks of rb`. One of these minor lobes has its maximum value (peak) atb` p=2. Six zeros of this plot are symmetrically located, b` np=7,n ... characteristichas identical lobes.Thus, the heights of intervening lobes decrease at the cost of the main lobe whenzeros are moved closer together. On the other hand, moving the zeros farther apartraises...
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... the following two-port network:3. Determine the Z-parameters of the following two-port network operating at800 MHz.4. Determine the Z-matrix for the following two-port network.5. The following ... to Zo1, as follows.a112V1 Zo1I12Zo1p23VS122Zo1p7:6:31S21is obtained by substituting (7.6.30) and (7.6.31) into (7.6.6), as follows.S21b2a1a20ÀZo2pI22p23VS122Zo1p232V2VS1Zo1Zo2s7:6:32Following ... scattering matrix of any lossless two-port network is unitary.Example 7.17: An ideal transformer is designed to operate at 500 MHz. It has 1000turns on its primary and 100 turns on its secondary...
... insertion loss of a Chebyshev ®lter is found as follows:L À20 log1011 BT2moocs266664377775 10 log101 BT2moocor,L 10 log101 ... 10Lc10À 1 100:3À 1 1And from (8.2.9) we haven 12Âlog1010L10À 1log10ooc log10B 0:5 Âlog10101:5À 1log101:3 6:52Therefore, 7 elements will be needed ... as the insertion loss of that two-port. It isgenerally expressed in dB. The fraction of the input power that is lost due tore¯ection at its input port is called the return loss. The ratio of...
... delivered to the load.(b) Using the value of Zsfrom part (a),®nd the Thevenin equivalent circuit atthe load end and evaluate the power delivered to the load.384SIGNAL-FLOW GRAPHS AND APPLICATIONSand,L1 ... 9.3.356SIGNAL-FLOW GRAPHS AND APPLICATIONS14. (a) Find the value of the source impedance that results in maximum powerdelivered to the load in the circuit shown below. Evaluate the maximumpower ... expressed in dB as follows:GTdB10 log5:4872%7:4dBGPdB10 log5:9374%7:7dBand,GAdB10 log5:8552%7:7dBPOWER GAIN EQUATIONS379and,L8 S13S31ÀDÀSTherefore,various terms...
... 0:8, jGin4 GHzj 0:75, andjGin5 GHzj 0:71.Return loss at 3 GHz 20 log100:8À1:94 dB.Return loss at 4 GHz 20 log100:75À2:5dB.Figure 10.11 RF circuit designed for ... For the source side, we can follow the path O±E±B, and therefore, an open-circuited shunt stub of 0:161 l followed by a 0.076 l-long transmission line canprovide the desired admittance. The ... among the basic building blocks of an electronic system. Whilevacuum tube devices are still used in high-power microwave circuits, transistorsÐsilicon bipolar junction devices, GaAs MESFET, heterojunction...
... OSCILLATORS493Phase-Locked Loop TerminologyHold-in Range: This is also called the lock range, the tracking range, or thesynchronization range. If reference frequency fris slowly changed from ... Therefore, these varactors provide a much more linear tuningcharacteristic than the abrupt type. These diodes are preferred for tuning over a widefrequency band. An octave tuning range can ... fB 50 À 0:5 MHzor,0:5 MHz fB 49:5 MHzHence, the frequency divider setting, NB, in loop B ranges as follows:5 NB 495Loops A and B use same reference frequency, and therefore, they have...