Transceiver and System Design for Digital Communications

1 Transceiver Design
1.1 Frequency of Operation
1.2 Transmitter
1.2.1 Power from the Transmitter
1.2.2 Transmitter Component Losses
1.2.3 Transmitter Line Losses from the Power Amplifier to the Antenna
1.2.4 Transmitter Antenna Gain
1.2.5 Transmitter Antenna Losses
1.2.6 Transmitted Effective Isotropic Radiated Power
1.3 Channel
1.3.1 Free-Space Attenuation
1.3.2 Propagation Losses
1.3.3 Multipath Losses
1.4 Receiver
1.4.1 Receiver Antenna Losses
1.4.2 Receiver Antenna Gain
1.4.3 Receiver Line Losses from the Antenna to the LNA
1.4.4 Receiver Component Losses
1.4.5 Received Signal Power at the Output to the LNA
1.4.6 Receiver Implementation Loss
1.4.7 Received Power for Establishing the Signal-to-Noise Ratio of a System
1.4.8 Received Noise Power
1.4.9 Noise Figure
1.4.10 Received Noise Power at the Detector
1.4.11 Receiver Bandwidth
1.4.12 Received Eb/No at the Detector
1.4.13 Receiver Coding Gain
1.4.14 Required Eb/No
1.5 The Link Budget
1.5.1 Spread Spectrum Systems
1.5.2 Process Gain 26
1.5.3 Received Power for Establishing the Signal-to-Noise Ratio for a Spread Spectrum System
1.5.4 Link Budget Example
1.6 Summary
References
Problems

2 The Transmitter
2.1 Basic Functions of the Transmitter
2.1.1 Transmit Antenna
2.1.2 Transmit/Receive Device
2.1.3 RF Power Amplifier
2.1.4 Upconverter
2.1.5 Sum and Difference Frequencies Generated in the Upconversion Process
2.1.6 Modulator
2.2 Voltage Standing Wave Ratio
2.2.1 Maximum Power Transfer Principle
2.3 Digital Communications
2.3.1 Digital versus Analog Communications
2.3.2 Software Programmable Radios and Cognitive Radios
2.4 Digital Modulation
2.4.1 Binary Phase-Shift Keying
2.4.2 Differential Phase-Shift Keying
2.4.3 Quadrature Phase-Shift Keying
2.4.4 Offset QPSK
2.4.5 Higher Order PSK
2.4.6 p/4 Differential QPSK
2.4.7 Differential 8-Level PSK
2.4.8 16-Offset Quadrature Amplitude Modulation
2.4.9 Phasor Constellations and Noise Immunity
2.4.10 BPSK versus QPSK Constellation Comparison
2.4.11 Variations in PSK Schemes
2.4.12 Continuous Phase PSK
2.4.13 Spectral Regrowth
2.4.14 Minimum Shift Keying
2.4.15 Frequency-Shift Keying
2.4.16 Sidelobe Reduction Methods
2.4.17 Ideal Shaping Filter
2.5 Direct Sequence Spread Spectrum
2.5.1 Frequency-Hopping Spread Spectrum
2.5.2 Spread Spectrum
2.5.3 Jammer Resistance
2.5.4 Despreading to Realize Process Gain in the Spread Spectrum System
2.5.5 Maximal Length Sequence Codes
2.5.6 Maximal Length PN Code Generator
2.5.7 Maximal Length PN Code Taps
2.5.8 Gold Codes
2.5.9 Other Codes
2.5.10 Spectral Lines in the Frequency Domain
2.6 Other Forms of Spread Spectrum Transmissions
2.6.1 Time Hopping
2.6.2 Chirped-FM
2.7 Multiple Users
2.7.1 Other Methods for Multiuser Techniques
2.7.2 Orthogonal Signals
2.7.3 Quadrature Phase Detection of Two Signals
2.7.4 Orthogonal Frequency Division Multiplexing
2.7.5 Other OFDM Techniques
2.8 Power Control
2.9 Summary
References
Problems

3 The Receiver
3.1 Superheterodyne Receiver
3.2 Basic Functions of the Receiver
3.3 Receiver Antenna
3.4 Transmit/Receive Device
3.5 Image Reject Filter
3.6 Low-Noise Amplifier
3.7 RF Downconverter
3.8 Mixers
3.8.1 High-Level or Low-Level Mixers
3.8.2 High-Side or Low-Side Injection
3.8.3 Mixer Spur Analysis—Level of Spurious Responses and Intermods
3.8.4 Sixth-Order Analysis
3.9 Automatic Gain Control
3.10 IF Downconverter
3.11 Splitting Signals into Multiple Bands for Processing
3.12 Phase Noise
3.13 Bandwidth Considerations
3.14 Filter Constraints
3.15 Group Delay
3.16 Analog-to-Digital Converter
3.17 Sampling Theorem and Aliasing
3.18 Anti-Aliasing Filter
3.19 Dynamic Range/Minimum Detectable Signal
3.20 Types of DR
3.20.1 Amplitude DR
3.20.2 Frequency DR
3.20.3 Single-Tone Frequency DR
3.20.4 Two-Tone Frequency DR
3.21 Second- and Third-Order Intermodulation Products
3.22 Calculating Two-Tone Frequency DR
3.23 System DR
3.24 Tangential Sensitivity
3.25 Digital Signal Processor
3.26 Summary
Reference
Problems

4 AGC Design and PLL Comparison
4.1 AGC Design
4.2 AGC Amplifier Curve
4.3 Linearizers
4.4 Detector
4.5 Loop Filter
4.6 Threshold Level
4.7 Integrator
4.8 Control Theory Analysis
4.8.1 AGC Design Example
4.9 Modulation Frequency Distortion
4.10 Comparison of the PLL and AGC Using Feedback Analysis Techniques
4.11 Basic PLL
4.12 Control System Analysis
4.13 Detector
4.14 Loop Filter
4.15 Loop Gain Constant
4.16 Integrator
4.17 Conversion Gain Constant
4.18 Control Theory Analysis
4.19 Similarities between the AGC and the PLL
4.20 Feedback Systems, Oscillations, and Stability
4.21 Summary
References
Problems

5 Demodulation
5.1 Carrier Recovery for Suppressed Carrier Removal
5.1.1 Squaring Loop
5.1.2 Costas Loop
5.1.3 Modified Costas Loop and Automatic Frequency Control Addition
5.2 Demodulation Process to Remove Spread Spectrum Code
5.2.1 Sliding Correlator
5.2.2 Pulsed Matched Filter
5.3 Pulse Position Modulation
5.4 Code Division Encoding and Decoding
5.5 Coherent versus Differential Digital Modulation and Demodulation
5.5.1 Coherent Demodulation
5.6 Symbol Synchronizer
5.7 The Eye Pattern
5.8 Digital Processor
5.9 Intersymbol Interference
5.10 Scrambler/Descrambler
5.11 Phase-Shift Detection
5.12 Shannon’s Limit
5.13 Summary
References
Problems

6 Basic Probability and Pulse Theory
6.1 Basic Probability Concepts
6.2 The Gaussian Process
6.3 Quantization and Sampling Errors
6.4 Probability of Error
6.5 Probability of Detection and False Alarms
6.6 Pulsed System Probabilities Using the BDF
6.7 Error Detection and Correction
6.7.1 Error Detection
6.7.2 Error Detection Using Parity
6.7.3 Error Detection Using Checksum
6.7.4 Error Detection Using CRC
6.7.5 Error Correction
6.7.6 Error Correction Using Redundancy
6.7.7 Forward Error Correction
6.7.8 Interleaving
6.7.9 Types of FEC
6.7.10 Viterbi Decoder
6.7.11 Turbo and Low-Density Parity Check Codes
6.8 Theory of Pulse Systems
6.9 PN Code
6.10 Summary
References
Problems

7 Multipath
7.1 Basic Types of Multipath
7.2 Specular Reflection on a Smooth Surface
7.3 Specular Reflection on a Rough Surface
7.4 Diffuse Reflection
7.5 Curvature of the Earth
7.6 Pulse Systems (Radar)
7.7 Vector Analysis Approach
7.8 Power Summation Approach
7.9 Multipath Mitigation Techniques
7.9.1 Antenna Diversity
7.10 Summary
References
Problems

8 Improving the System against Jammers
8.1 Burst Jammer
8.2 Adaptive Filter
8.3 Digital Filter Intuitive Analysis
8.4 Basic Adaptive Filter
8.5 Least Mean Square Algorithm
8.6 Digital/Analog ALE
8.7 Wideband ALE Jammer Suppressor Filter
8.8 Digital Circuitry
8.9 Simulation
8.10 Results
8.11 Amplitude and Phase Suppression Results
8.12 Gram-Schmidt Orthogonalizer
8.13 Basic GSO
8.14 Adaptive GSO Implementation
8.15 Intercept Receiver Comparison
8.16 Summary
References
Problems

9 Cognitive Systems
9.1 The Environment
9.1.1 Jammers
9.1.2 Channel Degradation
9.2 Basic Cognitive Techniques
9.2.1 Dynamic Spectrum Access
9.2.2 Adaptive Power/Gain Control
9.2.3 Cognitive Techniques Using Modulation Waveforms
9.2.4 Spread Spectrum for Increased Process Gain against Jammers
9.2.5 Adaptive Error Correction
9.2.6 Adaptive Filter for Jammer Mitigation
9.2.7 Dynamic Antenna Techniques Using AESAs
9.2.8 Multipath Communications
9.2.9 Multiple Antennas
9.2.10 Network Configurations
9.2.11 Cognitive MANETs
9.3 Cognitive System Solution
9.4 Summary
References
Problems

10 Broadband Communications and Networking
10.1 Mobile Users
10.1.1 Personal Communications Services
10.1.2 Cellular Telephone
10.1.3 Industrial, Scientific, and Medical Bands
10.2 Types of Distribution Methods for the Home
10.2.1 Power Line Communications
10.2.2 Home Phoneline Networking Alliance
10.2.3 Radio Frequency Communications
10.2.4 IEEE 802.11
10.2.5 Bluetooth
10.2.6 WiMAX
10.2.7 LTE
10.3 LMDS
10.4 MMDS
10.5 Universal Mobile Telecommunications System
10.6 4G
10.7 Mobile Broadband Wireless Access IEEE 802.20
10.8 MISO Communications
10.9 MIMO Communications
10.10 QoS
10.11 Military Radios and Data Links
10.11.1 The Joint Tactical Radio System
10.11.2 SDRs
10.11.3 Software Communications Architecture
10.11.4 JTRS Radios (Clusters)
10.11.5 Waveforms
10.11.6 JTRS Network Challenge
10.11.7 Gateway and Network Configurations
10.11.8 Link 16
10.11.9 Link 16 Modulation
10.11.10 TDMA
10.11.11 ‘‘Stacked’’ Nets
10.11.12 Time Slot Reallocation
10.11.13 Bit/Message Structure
10.12 Summary
References
Problems

11 Satellite Communications
11.1 Communications Satellites
11.2 General Satellite Operation
11.2.1 Operational Frequencies
11.2.2 Modulation
11.2.3 Adaptive Differential Pulse Code Modulation
11.3 Fixed Satellite Service
11.4 Geosynchronous and Geostationary Orbits
11.5 Ground Station Antennas
11.6 Noise and the Low-Noise Amplifier
11.7 The Link Budget
11.7.1 EIRP
11.7.2 Propagation Losses
11.7.3 Received Power at the Receiver
11.7.4 Carrier Power/Equivalent Temperature
11.8 Multiple Channels in the Same Frequency Band
11.9 Multiple Access Schemes
11.10 Propagation Delay
11.11 Cost for Use of the Satellites
11.12 Regulations
11.13 Types of Satellites Used for Communications
11.14 System Design for Satellite Communications
11.15 Summary
References
Problems

12 Global Navigation Satellite Systems
12.1 Satellite Transmissions
12.2 Data Signal Structure
12.3 GPS Receiver
12.3.1 GPS Process Gain
12.3.2 Positioning Calculations
12.4 Atmospheric Errors
12.5 Multipath Errors
12.6 Narrow Correlator
12.7 Selective Availability
12.8 Carrier Smoothed Code
12.9 Differential GPS
12.10 DGPS Time Synchronization
12.11 Relative GPS
12.12 Doppler
12.13 Kinematic Carrier Phase Tracking
12.14 Double Difference
12.15 Wide Lane/Narrow Lane
12.16 Other Satellite Positioning Systems
12.17 Summary
References
Problems

13 Direction Finding and Interferometer Analysis
13.1 Interferometer Analysis
13.2 Direction Cosines
13.3 Basic Interferometer Equation
13.4 Three-Dimensional Approach
13.5 Antenna Position Matrix
13.6 Coordinate Conversion Due to Pitch and Roll
13.7 Using Direction Cosines
13.8 Alternate Method
13.9 Quaternions
13.10 Summary
References
Problems