EE5900-2: course topics

List of Topics Covered

Week 1: Introduction to Spread Spectrum Communications
Section 2-1, 2-2
1/17/01
Non-spread communications: typical non-spread systems; when is bandwidth efficiency most important? Other communication circumstances
Spread spectrum communications: loose definition, history
1/19/01
Basic spread spectrum signal types: direct-sequence SS, frequency-hop SS, chirped SS, hybrid SS
Examples using spread spectrum signals: channels with interference, channels with multiple users, covert communications, and high-resolution radar
1/22/01
Applications - pulsed/partial-band noise jamming: performance analysis in non-spread BPSK; mitigating the jamming effects using spread spectrum
Applications - multiple users of the same channel: narrowband signaling solution; spread spectrum multi-access solution
Applications - convert communications: hypothesis testing in energy detection; how does a wideband signal defeat radiometer detector?
Week 2: BPSK Direct Sequence Spread Spectrum
Section 2-3.1
1/24/01
Direct sequence spread spectrum transmitter: generic structure, DS-BPSK transmitter structure
DS-BPSK modulation: formulation, spectrum, bandwidth efficiency
1/26/01
Review of random process and power spectrum density: Concepts of WSS process, cyclostationary process, autocorrelation, PSD, and power
PSD analysis of digital signals: spreading sequence, random binary pulse train, and non-spread BPSK modulated signal
Handout: Random Processes and Power spectrum Density
1/29/01
PSD analysis of DS-BPSK modulated signal
DS-BPSK receiver: receiver structure, spectral characteristics of the received signal components (DS-BPSK signal, interference, noise), effective jamming power
Week 3: Review of Digital Communications Concepts
Section 1-2, 1-3
1/31/01
Probability of error for DS-BPSK communications: PDF of signal components at the output of matched filter (desired binary signal, spread interference, noise), error probability
Overview of digital communication systems: typical system structure and functional blocks
2/2/01:
Functional pairs in digital communications: spreading & dispreading, modulation & demodulation, pulse shaping and matched filtering
Signal space concepts: signal space and its dimension, basic signal set, orthonormal basic set, vector representations of signals and signal operations
2/5/01:
Signal detection for M-ary baseband communications: matched filter concepts and implementations, decision region, and probability of error
Handout: Signal Detection in M-ary Communications
Week 4: Winter Carnival
2/7/01:
Digital communications: deciding the decision regions and evaluating the probability of error in terms of Eb/No for a given signal constellation
Example constellations: 4-ary multi-amplitude signaling, PSK
Week 5, 6: Frequency-Hop Spread Spectrum, Summary of Chapter 2
2/12/01: Section 2.3-2
QPSK and DS-QPSK: implementations, BW efficiency, jamming power reduction
2/14/01, 2/16/01: Section 2-4.1
Slow-hop signals: transmitter structure, PSD of FHSS, processing gain, generating hopping sequence
Handout: PSD of Slow-Frequency-Hopped Signals
2/19/01: Section 2.4-2, 2-4,3
Coherent slow-hop SS: receiver structure, interference reduction by FH
Non-coherent fast-hop SS: definition of fast-hop, transmitter and receiver, PSD of transmitted signal, frequency down-converter, frequency diversity gain
2/21/01: Handout: Summary of Spread Spectrum Signals
2/23/01: Homework problems in chapter 2
Week 7: Linear Recursive Sequences
2/26/01: Section 3-1, 3-2.1
Overview of chapters 2, 3, 4, 5
Desired properties of the spreading waveform: wideband, deterministic, random-like, good auto-/cross-correlation properties
Approach to spreading sequence generation: finite field algebra, shift register circuits, M-sequence and Gold codes
Basic correlation functions: auto-correlation, cross-correlation, discrete cross-correlation functions (CCF)
2/28/01: Section 3-2.2
Finite Field Basics: definitions of finite fields (Galois field), prime fields, and extended prime fields, properties of finite field, multiplicative and additive inverses, finite field by polynomial operations, primitive polynomial, multiplication and multiplicative inverse in GF(2^{m})
3/2/01: Section 3.2-3
Linear shift register sequences and sequence generator fundamentals: binary sequence in polynomial representation, multiplier and divider circuits by linear shift registers, period length of the output sequence (while the period of a particular sequence depends on the initial register states, the maximum possible period of a s. r. is decided by the connections)
M-sequences: definitions and applications in DS-SS
Week 8: Spring Break
Week 9: M-Sequences
3/12/01: Section 3-3.1,3-3.2
Properties of M-sequences: Review of linear recursive sequences
PSD of spreading waveforms generated from M-sequences: discrete Fourier Series representations, comparison to i.i.d. random binary sequences
3/14/01: Section 3-3.4, 3.3-6
Partial auto-correlation functions: definition, applications, and simulations
Generation of specific delays of an M-sequence: objective, determining the initial condition yielding a specific delay
3/16/01:
Homework problems in chapter 3
Week 10: Midterm
3/19/01:
Review of Chapter 3: linear recursive sequences -- why use l.r.s., state, phase, and length; M-sequence -- basic elements, generation parameters, configurations, properties, PSD, generation of specific delays
An example in chapter 2: design of DS/FH-SS for jamming suppression
Week 11: Other Code Generators
3/26/01: Section 3.4
Gold codes: problem description of code design in CDMA cellular systems, solution by phase shifts of a long M-sequence, solution by Gold codes, construction of Gold code family, example applications
3/28/01:
Walsh Codes and its applications in IS-95 CDMA system
3/30/01: Midterm problem solving
Week 12: Basics of Delay Lock Loop
4/2/01: Section 4.1, 4.2
Code tacking: problem statement, basic model of code tracking loops, wideband loop filter vs. narrowband, idealized wideband signal tracking, code tracking outline
4/4/01: Section 4.3
Baseband DLL: assumptions, mixed analog-digital DLL circuit, parameter design with noiseless signals
4/6/01: Section 4.3
Baseband DLL with noise: discriminator noise output PSD
Week 13: Tracking Loops
4/9/01: Section 4.3
Equivalent linear model of baseband DLL: equivalent circuit, inputs, linear transfer function
Loop performance: dynamic performance analysis, steady-state noise analysis, jitter power, equivalent noise bandwidth, loop SNR
Baseband DLL summary
4/11/01: Section 4.4-4.9
Non-coherent delay-lock tracking loop: drawbacks of baseband DLL, non-coherent DLL circuit, discriminator DC term analysis
Briefing of other tracking loops: Tau-Dither tracking loop, other data/spreading modulations
Summary
4/13/01:
Homework problem solving for chapter 4
Introduction to digital receivers: Assumptions in "digital", analog receiver structure for digital modulations, effect of imperfect timing recovery in matched filter output
Week 14: Digital Receiver
4/16/01:
Basic digital receiver structure: rotating data, pre-filter, sampling rate, DSP block, functions implemented in DSP, key constraint - sampling rate and data rate
Digital timing recovery: equivalent representation of desired timing, Interpolation theory, two approaches for interpolation - digital and partial digital
4/18/01:
Digital matched filter: briefing on digital MF using transversal filter, problem description of demodulation with digital MF, digital solution MF using interpolation, decimation and timing control, block diagram
4/20/01:
Digital phase recovery: problem statement for post-MF phase recovery, two problems - phase estimation and phase de-rotation
Digital phase locked loop: comparison to analog PLL, a tracking circuit without data modulation, first-order analysis, NCO, decision feedback tracking system with BPSK modulation
Help on course project - DLL: handout
Week 15: Code acquisition
4/23/01: Section 5.1, 5.2
Introduction to initial synchronization: problem description - input and desired output, possible solutions, time-frequency uncertainty plane, serial code acquisition search strategy, high-level circuit diagram
4/25/01: Section 5.3
Analysis on acquisition effectiveness

Last updated: 23-Apr-01