Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Q. Illustrate Differential phase-shift keying?
In order to eliminate the need of a local carrier, DPSK has been developed in which the receiver uses the received signal to act as its own carrier. Figure shows the functions of a DPSK system in which the leftmost product operation along with 1-bit delay is the differential encoder. The digital signal d(t) is a polar waveform of levels ±1, corresponding to binary digits 1 and 0, respectively. The output signal a(t) from the differential encoder PSK-modulates a carrier to produce the DPSK signal sDPSK(t). The product device followed by the wide-band low-pass filter acts as the coherent detector. The two inputs to the product device are obtained from the output of a filter matched to the input pulse in a single bit interval. Note that the 1-bit delayed input to the product device serves the purpose of the local oscillator for the coherent detector; that is to say, the DPSK waveform in a given bit interval serves as its own local-oscillator signal in the following bit interval.
In Figure, si(t) is the signal component of the matched filter output, and sd(t)isthe signal component of the detector output. If the phases of both si(t) and si(t - Tb) are the same, sd(t) is then a positive voltage; if their phases differ by π radians, sd(t) will then be a negative voltage. These voltages will have maximum amplitudes at the sample time at the end of the bit interval. Because the sign of the voltage at the sampler depends upon the phase relationship between si(t) and its delayed replica, and the sign of sd(t) is of the same form as d(t), the original digital bit sequence can be determined by sampling to decide the sign of the detector output. Figure illustrates an example sequence of message binary digits, modulator wave- forms in DPSK, and phase and polarity relationships as applied to DPSK message recovery.
Speed Control of DC Shunt Motor V dc the output of rectifying circuit which is applied to the motor field as shown in figure for armature voltage V dc is controlled by
Explain SEGMENT assembler directive with example. SEGMENT: This directive described to the assembler the start of a segment along with name segment-name. The seg
XTHL Exchange top of the stack with HL Instruction The contents of top two location of the stack are exchanged with the contents of HL register pair. The contents of reg
Using the LM741operational amplifier build a current amplifier with the voltage gain of |A V | = 300 v/v ± = 20% . Measure all necessary parameters of the amplifier (as per delive
Assume you are working for an SME operating in the microelectronics sector. You are required to plan a new product development project. This is an internal project, so it does not
High-pass T filters: Three-element filters can comprise a 'T' or 'π' topology and in either geometries, a low-pass, band-pass, high-pass, or band-stop characteristic is feasib
Q. Explain stages of attending to Rail fracture? Various stages of attending to Rail fracture / weld failure in a L.W.R. track in field - Equipment required - i) Special
Design and draw a circuit using the cascade system to operate two cylinders (A and B) which, on the operation of a start valve, produces the sequence A – B + B – A+. The cylinders
A Zener diode has the specifications VZ=6.8V and PDmax.=500mW. Assume RZ=0. (a) Find the maximum allowable current iZ when the Zener diode is acting as a regulator. (b) If a sing
how can I simulate air variable capacitors in cst simulator?
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd