17-Phys-B4 Signals and Communications
Worked solutions to 5 past sittings (2013–2016), 35 questions. Pick a sitting, or start from a topic below.
Topics across the sittings
Topics that come up in more than one sitting, taken from the headings of our worked solutions. A topic counts once per sitting.
- Stability (3 sittings): December 2016 Q2 · December 2015 Q1 · December 2014 Q6
- Bandwidth (2 sittings): December 2016 Q3 · December 2015 Q5
- Bit Rate (2 sittings): December 2016 Q4 · December 2015 Q4
- Demodulation (2 sittings): December 2016 Q6 · December 2014 Q7
- Efficiency (2 sittings): December 2016 Q3 · December 2015 Q3
- Envelope (2 sittings): December 2015 Q3 · December 2014 Q7
- Impulse Response (2 sittings): December 2016 Q2 · December 2015 Q1
- Power (2 sittings): December 2016 Q3 · December 2015 Q5
- Sampling Rate (2 sittings): December 2016 Q4 · December 2015 Q4
- Spectrum (2 sittings): December 2015 Q3 · December 2014 Q7
- Transfer Function (2 sittings): December 2015 Q1 · December 2014 Q6
Questions by sitting
December 2016
- Question 1: Periodic Pulse Train Through Ideal Low-Pass and High-Pass Filters
- Question 2: Discrete-Time IIR System — Realization, Impulse Response, Stability
- Question 3: DSB and AM Modulation of a Staircase Message — Power, Efficiency, Bandwidth
- Question 4: PCM System Design — Sampling Rate, Bit Rate, SNR
- Question 5: Spectral Analysis of a Composite Message — Bandwidth Under DSB and SSB
- Question 6: VCO-Based FM Modulator — Output Expression, Demodulation, Carson Bandwidth
December 2015
- Question 1: Discrete-Time Feedback System — Transfer Function, Stability, Impulse Response
- Question 2: Fourier Series, Power Spectral Density and Bandpass Filtering of a Periodic Pulse Train
- Question 3: Amplitude Modulation — Waveform, Efficiency, Spectrum, Envelope, Detector
- Question 4: PCM — Sampling Rate, Quantization Bits, Bit Rate, TDM Bandwidth
- Question 5: Multitone FM — Message, Power, Peak Deviation, Bandwidth, Demodulator
- Question 6: Bandpass Spectral Mirroring and Frequency Conversion with a Limited Local Oscillator
December 2014
- Question 1: Fourier Transform, Spectra and Filtering of a Delayed Exponential
- Question 2: Half-Wave Rectifier, AC Coupling and Integration of a Cosine
- Question 3: PCM Sampling, Quantization and Multiplexed Bit Rate
- Question 4: Modulator Waveforms and Demodulators for a Square-Wave Message
- Question 5: Superheterodyne Receiver — LO Tuning, Image Frequency and Front-End Filter
- Question 6: Discrete-Time Causal System — Difference Equation, Transfer Function and Stability
- Question 7: AM Signal — Time Domain, Spectrum, Envelope and Demodulation
May 2014
- Question 1: Sampling and Reconstruction of a sinc² Signal
- Question 2: Sampling a Two-Tone Message and the Effect of Aliasing
- Question 3: FT Properties — Time-Scaling, Shift and Modulation of a sinc Pulse
- Question 4: FM Spectrum — Reading Modulation Index from a Bessel-Line Plot
- Question 5: PCM Design for a Television Signal
- Question 6: Standard AM — Recovering the Message, Modulation Index and Power Efficiency
- Question 7: A Nonlinear/Filter Cascade — Linearity, Distortionless Transmission, and Black-Box Testing
- Question 8: Regions of Convergence, Causality/Stability, and Inversion of a Rational z-Transform
- Question 9: 4-ary PCM Design for an Audio Signal
- Question 10: Matched Filtering and Optimum Sampling for Split-Phase (Manchester) Signalling
December 2013
- Question 1: Trigonometric and Exponential Fourier Series of a Multitone Signal
- Question 2: Recovering the Modulating Signal from an Angle-Modulated Phase Function
- Question 3: Sampling $x(t)=\mathrm{sinc}^2(10\pi t)$ at Three Rates
- Question 4: Fourier Transform Properties from a Piecewise-Linear Signal, Without Computing $X(j\omega)$ Explicitly
- Question 5: Partial-Fraction Inversion of a Right-Sided z-Transform, Two Ways
- Question 6: Transmitter Power Budget for DSB, and Square-Wave AM/DSB Envelopes