Module Aims

This module aims to bring together the system, circuit and technology issues to be faced when realising a complete wireless transceiver function in silicon for mass market use.
The course will start with a review of the system level issues, discussing applications, modulation schemes and specifications. Particular emphasis will be given to systems using digital modulation where data recovery schemes are important.

Popular architectures will be compared, eg superhet vs direct conversion in terms of the IC implementation issues and the specifications of the building blocks required. The question of which technology (principally BICMOS vs CMOS) is most suited will be discussed. The course will then consider the transistor level design of typical cells in an integrated rather than matched environment. This will include LNA, mixer, IF and filtering, A/D interface, and VCO


Learning Objectives

On successful completion of the module, the delegates will have obtained an appreciation of:

• Appreciation of specifications, RF and baseband signals in common telephony and data radio systems
  
• Understanding of radio architectures suitable for high levels of integration
  
• Appreciation of active and passive components on IC technology and their limitations
  
• Understanding of common circuit level functions essential to integrated radio architectures

Background to the Module

Cellular telephone and local wireless data communications applications have fuelled an explosive demand for highly integrated radio transceiver functions. The architectures used and the design techniques used depart significantly from the classical matched impedance building block approach, and the whole radio system as well as the target technology must be considered in the design choices. This course aims to bring together the radio system and transistor level designers' views in the problem of low cost high performance radio design.

Prerequisite Knowledge

• Bipolar and MOS transistor construction and physics
  
• DC and AC network analysis skills
  
• Basic analogue IC design
  
• Basic knowledge of matching and S-parameter methods
  
• Basic knowledge of filter theory
  
• Basic knowledge of classical radio systems
  
• Elementary appreciation of modulation schemes
  
• Basic circuit simulation CAD skills (SPICE)
  
  

Assessment Weighting

Delivery and Assignments

Pre-Residential

• Study pack covering the course material and reading list
  
• Assignment carrying 10% of marks

Residential Week (34 hours contact time)

• Lectures
  
• Tutorial classes/design exercises

Post Residential Study

• Design assignment with report (2000-4000 words or equivalent)
  
• Supervised Examination (3 questions from 5 in 2 hours)

Syllabus

Review of radio signals, modulation and demodulation schemes
AM, FM, PM, FSK, QPSK, QAMSignal Spectra; I/Q modulation and demodulation schemes; Spread Spectrum systems, S/N vs BER :Partition between analogue and digital signal processsing

Overview of common Radio System Specifications
Key RF spec points for AMPS, DECT, GSM, CDMA, Bluetooth, Hiperlan

RF IC technology and components
Passive components in RF technology and their models
Capacitors and resistors
Planar Inductors
Packages and bondwires
HF Bipolar transistors and models
SiGe bipolar
CMOS - HF circuit and noise models

Review of classical radio technique definitions
Transmission lines, Matching networks, S-parameters, smith charts, noise figure, Noise in A/D conversion process

Receiver Specs & Measurements
IP2/IP3, 1dB compression, etc
Origins of these
Matched system signal definitions vs On-chip signals

Review of filter Technologies
Passive RLC, SAW, on-chip analogue, digital

Receiver Architectures
Basic SuperhetImage frequencies
Single and double conversion
Choice of IF : low vs high vs DC
Other spurious responses
Frequency planning
Realisable B/W vs IF values
Double Superhet
I/Q Architectures
Gain & Phase
Matching Needs
Noise Figures and Gain distribution
LO Noise
A/D converter specs

LNA Design
Specifications
Bipolar designs.
Single transistor
Cascode
Differential
Input matching
Feedback techniques
Inductive degeneration
CMOS LNAs

RF and IF VGA Design
Specs and requirements
Variable vs switched gain
Gm variation
Signal path steering
Attenuator blocks
Bipolar and MOS implementations
Matching, linearity and noise variation

Mixer Design
Mixer requirements and specs
Input and output conditions
Bipolar mixers
"Gilbert" type
Other bipolar mixers
CMOS mixers
"Gilbert" equivalent
"Passive"
Sub-sampling
Image Suppression

Baseband Filtering
Filter requirements
Gm-C integrators
Gyrators
Op-Amp RC
Tuning schemes
Polyphase filters
Matching
Image Suppression

A/D Circuits
Where to partition chips
Anti-aliasing requirements with analogue
BB filter
Direct IF conversion
SD, SA and Folding

TX Architecture
Demands of Constant vs non-constant envelope modulation
Direct output
Upconversion
LO Feedthrough
Pulse formation by DAC
DAC Specs
Tx VGA Circuits
Driver linearity.

LO and synthesiser specifications
Tuning range, phase noise

LO and synthesiser circuits
Integrated Oscillators
Tuning circuits
High speed prescalers
Dual modulus division
Fractional N concepts
Phase detector circuits
Dead zone behaviour

Recommended Texts

Conference and Journal Papers

W Redman-White
University. of Southampton
Version 2 17/2/2002