Local Oscillator Calibration, Receiver Tuning and Cryostat Control Software

Todd Hunter, Bob Wilson & Robert Kimberk

Executive Summary

This document describes the software interface to the local oscillator, receiver, and cryostat systems of the SAO SubMillimeter Array. Software is being developed to perform laboratory calibration and real-time antenna-based tuning of the local oscillator (LO) chain (Gunn oscillators, multipliers, attenuators, harmonic mixers) and the SIS receiver system as a function of the LO frequency. The software will implement flexible algorithms designed to automatically achieve optimal ``push-button'' tuning.

• Overview
• Hardware Components
  • Required Interfaces
  • Supported GPIB Devices
  • Supported VXI Devices
  • Supported VME Devices (future)
• Software Components
  • LynxOS Directory Structure (antenna computer)
  • Windows NT Directory Structure
  • Summary of Source Code Files
  • Header Files (i.e. C #include files)
  • Linker Files for the 80C196 compiler
  • Makefile targets for tune6
  • Hardware Lookup Tables
• Gunn oscillator frequency tuning
• Cookbook for calibrating a new LO chain
  • Gunn oscillator calibration
  • Multiplier calibration
  • Receiver calibration
• Summary of tune6 interactive commands
• Configuration Switches and Algorithm Constants
  • True/False Compiler Directives
  • Gunn temperature correction constants
  • Receiver insert configuration constants
  • GPIB addresses
  • RS485 addresses and packet design constants
  • IPC-related constants
  • Spectrum analyzer specific constants
  • Power meter specific constants
  • PLL-specific constants
  • DAC-specific constants
  • ADC-specific constants
  • Motor-specific constants
    • Motor numbers (in motor.h)
    • Motor limits (in motor.h)
    • Motor stepsizes
  • IF reference specific constants
  • Lookup table specific constants
  • Gunn oscillator specific constants
  • Calibration routine constants
  • Real-time optimization constants
  • Constants used by the ScanTuner() routine
  • Simple constants
  • Tuning result codes
• Real-time tuning algorithm
• About this document ...