Contents

• Preface
• General Theory
  • Signals in Radio Astronomy
    • Introduction
    • Properties of the Gaussian
    • The Wiener-Khinchin Theorem
    • The Sampling Theorem
    • The Central Limit and Pairing Theorems
    • Quasimonochromatic and Complex Signals
    • Cross Correlations
    • Mathematical details
  • Interferometry and Aperture Synthesis
    • Introduction
    • The Radio Sky
    • Signals in Radio Astronomy
    • Interferometry
      • The Need for Interferometry
      • The Van Cittert Zernike Theorem
      • Aperture Synthesis
    • The Fourier Transform
  • Single Dish Radio Telescopes
    • Introduction
    • EM Wave Basics
    • Signals and Noise in Radio Astronomy
      • Signals
      • Noise
      • Signal to Noise Ratio
    • Antenna Patterns
    • Computing Antenna Patterns
  • Two Element Interferometers
    • Introduction
    • A Two Element Interferometer
    • Response to Quasi-Monochromatic Radiation
    • Two Element Interferometers in Practice
  • Sensitivity and Calibration for Interferometers
    • Sensitivity
    • Calibration
    • Further Reading
  • Phased Arrays
    • Introduction
    • Array Theory
      • The 2 Element Array
      • Linear Arrays of n Elements of Equal Amplitude and Spacing :
      • The Fourier Transform Approach to Array Patterns
    • Techniques for Phasing an Array
    • Coherently vs Incoherently Phased Array
    • Comparison of Phased Array with a Multi-Element Interferometer
    • Further Reading
  • Imaging With Dipolar Arrays
    • Early History of Dipole Arrays
    • Image Formation
    • Digital Beam Forming
    • Radio Telescopes with Digital Beam Forming Networks
      • The Clark Lake TEE-PEE-TEE Telescope
      • GEETEE: The Gauribidanur Array
      • MOST: The Molonglo Observatory Synthesis Telescope
      • Summary
    • Square Kilometer Array (SKA) Concept
    • Adaptive Beam Forming
    • Further Reading
  • Correlator I. Basics
    • Introduction
    • Digitization
      • Sampling
      • Quantization
      • Dynamic Range
    • Discrete Fourier Transform
      • Filtering and Windowing
    • Digital Delay
    • Discrete Correlation and the Power Spectral Density
    • Further Reading
  • Correlator - II: Implementation
    • Delay Tracking and Fringe Stopping
    • Spectral Correlator
      • FX Correlator
      • XF Correlator
    • Further Reading
  • Mapping I
    • Coordinate Systems
      • Angular Co-ordinates
      • Astronomical Co-ordinate System
      • Physical Coordinate System
      • Coordinate Transformation
    • 2D Relation Between Sky and Aperture Planes
    • Further Reading
  • Mapping II
    • Introduction
    • Weighting, Tapering and Beam Shaping
    • Gridding and Interpolation
    • Bandwidth Smearing
    • Time Average Smearing
    • Zero-spacing Problem
    • Further Reading
  • Deconvolution in sythesis imaging-an introduction
    • Preliminaries
    • The Deconvolution Problem
      • Interferometric Measurements
      • Dirty Map and Dirty Beam
      • The Need for Deconvolution
    • CLEAN
      • The Högbom Algorithm
      • The Behaviour of CLEAN
      • Beyond CLEAN
    • Maximum Entropy
      • Bayesian Statistical Inference
      • MEM Images
      • Noise and Residuals
    • Further Reading
  • Spectral Line Observations
    • Spectral Lines
    • Rest Frequency and Observing Frequency
    • Setting the Observing Frequency and the Bandwidth
    • Calibration
      • Gain Calibration
      • Bandshape Calibration
    • Smoothing
    • Continuum Subtraction
    • Line Profiles
    • Further Reading
  • Wide Field Imaging
    • Introduction
    • Mapping with Non Co-planar Arrays
      • Image Volume
      • Interpretation of the -term
      • Inversion Of Visibilities
    • Mosaicing
      • Scanning Interferometer
    • Further Reading
  • Polarimetry
    • Introduction
    • Polarization in Radio Astronomy
    • The Measurement Equation
    • Polarization Calibration
    • Further Reading
  • Ionospheric effects in Radio Astronomy
    • Introduction
    • Propagation Through a Homogeneous Plasma
    • Propagation Through a Smooth Ionosphere
    • Propagation Through an Inhomogeneous Ionosphere
    • Angular Broadening
    • Scintillation
    • Further Reading
  • Pulsar Observations
    • Introduction
    • Requirements for Pulsar Observations
      • Phased Array Requirements
      • Spectral Resolution Requirements
      • Requirements for Time Resolution and Accurate Time Keeping
      • Requirements for Polarimetry
      • Flux Calibration Requirements
    • Basic Block Diagram of a Pulsar Receiver
    • Dispersion and Techniques for its Correction
    • Pulse Studies
    • Interstellar Scintillation Studies
    • Pulsar Timing Studies
    • Pulsar Search
    • Further Reading
  
  
• The GMRT
  • An Overview of the GMRT
    • Introduction
    • Array Configuration
    • Receiver System
    • Digital Backends
  • GMRT Antennas and Feeds
    • Introduction
    • Types of Antennas
    • Characterizing Reflector Antennas
    • Computing Reflector Antenna Radiation Patterns
      • Aperture Efficiency
    • Design Specifications for the GMRT Antennas
      • Secondary Patterns
    • GMRT Feeds
      • Feed Placement
      • 150 MHz Feed
      • 327 MHz Feed
      • Dual-Frequency Coaxial Waveguide Feed
    • 1000-1450 MHz Feed
    • GMRT Antenna Efficiencies
    • Further Reading
  • The GMRT Servo System
    • Introduction
    • Objectives of the GMRT Servo System
    • The GMRT Servo System Specifications
    • Control System Description
      • Closed Loop Control Systems
      • Principles of Position Control
      • Position Loop Amplifier
      • Rate Loop Amplifier
      • Current Loop Amplifier
    • Servo Amplifiers
    • Servo Motors
    • Gear Reducers
    • Position Sensors
    • Dual Drive
    • Digital Controller
    • Servo Operational Commands
  • GMRT Receivers
    • Introduction
    • Overview of the GMRT Receiver Chain
    • Receiver Design Considerations
    • The Multi Frequency Front Ends
    • The Antenna Base Receiver
    • The Fiber-Optic Link
  • The GMRT Optical Fiber System
    • Introduction
    • The Laser Transmitter
      • Laser Specifications
    • The Optical Fiber
    • The Optical Receiver
    • Link Performance
  • Local Oscillator and Base-band Systems
    • Requirement for a Local Oscillator System at the GMRT
    • The Frequency Translation Scheme used at the GMRT
    • Generation of Phase-Coherent Local Oscillator Signals
    • Noise Calibration and Walsh Switching
    • The Base-band System
    • A Summary of Important Specifications
      • Array Frequency Reference
      • First LO Synthesiser
      • Second and Third LO Sources and Offset Frequency Sources
      • Fourth LO Synthesiser
      • Base-band System
  • A Control and Monitor System for the GMRT
    • Introduction
    • Overview
      • ONLINE
      • PCROUTER
      • COMH
      • ANTCOM or ABC
      • Servo Control Computer
      • Monitor and Control Modules
    • Signal Flow in the GMRT Control & Monitor System
      • Error Detection
    • Signal Modulation
      • Frequency Shift Keying
    • System specifications of the Control & Monitor system
      • Overview
      • Bit rates available for various services
      • Details of the various communication links
  • The GMRT Correlator
    • Introduction
    • An overview of the GMRT Correlator
      • ADC
      • Delay-DPC
      • FFT
      • MAC
    • Modes of operation of the GMRT correlator
      • Non-Polar Mode
      • Indian-Polar Mode
      • Polar Mode
    • Further Reading
  • The Data Acquisition System for the GMRT
    • Data Acquisition
    • Correlator Control
    • Monitoring the health of the correlator
    • Online processing of the data
      • The network of acquisition and processing
      • The software layout
      • Time stamping of data and it's accuracy
    • Further desirable features