Modeling & Simulation > Munnin-Huggin Pulse TOA Analysis and Generator

Muninn-Huginn - Trajectory Based Pulse TOA Generator

Perhaps Muninn-Huginn Can Be of Some Use to Those Experimenting or Developing Pulse Based Analysis Systems

The Muninn - Huginn simulation generates the time of arrival (TOA), time difference of arrival (TDOA), KeySight UXG like pulse definition words (PDWs) and other states associated with a dynamic platform ( the receiver/antenna(s)) and multiple transmitting radars sources. The system consists of two execuables, Muninn.exe a graphical user interface (GUI) and Huginn.exe the TOA computation engine which is a multithreaded / multicore application utlizing multicore architectures.

Muninn-Huginn generates detailed, pulse-to-pulse TOA data for transmitter and receiver platform supporting multiple RF receiving antennae. TOA data is calculated between a WGS84 receiver trajectory with platform antennae configuration/characteristics, one or more transmitter stationary trajectory, transmitter characteristics, and a description of the transmitter pulse sequence. Muninn-Huginn supports multiple transmitters and multiple transmitter modes throughout the scenario. Atmospheric effects and LOS obscurations are not modeled. Munnin-Huginn is not a radar model.

Muninn-Huginn allows the definition of 2...N receiver antennae, each with its own mounting and orientation data. One antenna is defined as the reference antenna which all TDOA data is relative to. The model assumes that each antenna is rigidly attached to the receiver's platform. Each antenna that comprise the receiver's antenna system can be positioned at a different location. Each antenna can also be pointed in a different direction relative to the receiver platform body centerline. The model independent trajectories and data sets for each transmitter to receiver antenna given the base trajectory and antennae positions. Huginn derives the TOA by solving the following nonlinear equation : Δρ=|Ri(T,ΔTi)-c ΔTi | ≤ ε where T = known time the pulse is transmitted, ΔTi = unknown time it takes the pulse to travel from the transmitter(n) to antenna i, Ri) (T,ΔTi)= distance between antenna i (when the pulse is received) and the transmitter (when the pulse is transmitted), c = speed of light, and ε = range error tolerance which is set to 1-nanometer

A Newton-Raphson numerical technique (successive approximation, function, function derivatives, an initial estimate, cubic spline) is used to iteratively estimate ΔT_i until the delta TOA is less than range error tolerance ( Δρ≤ ε). Experimentation has shown that Δρ is less than 1-nanometer after a single iteration. The TOA for antenna i is TOAi=T+ ΔTi. One can easily show that errors in TOAi and ΔTi are less than 10-8 nanoseconds.

The system requires time history trajectory file inputs in NST's .TRAJ0 format which may be created using our Pilot 3-DOF Model, , Waypoint Based 6-DOF Model, or Coarse Trajectory to High Resolution tool or your model with the correct output.

Huginn.exe accepts a XML formatted Huginn Configuration files (.XHC). A XHC configuration describes the scenario parameters, trajectories, options and specifies the resulting output file names for the CSV formatted coarse data and detailed pulse files as well as the archive SQLite database name and PDW filenames per antenna. The coarse data file describes the antenna states and detailed pulse file contains TOA, TDOA, and other data for each antenna. Huginn.exe can be executed as a standalone application from a Windows command window (single or batch file processing) or it may be launched from within the Muninn.exe GUI.

The Input XML Configuration File (.xhc) Contains:

Transmitter Mode Library
  • Defines transmitter modes (transmit power, carrier frequency, polarity) and optional parameters that are needed to generate KeySight compatible PDW files. It also defines pulse trains. One or more transmitter models. A transmitter model consists of a stationary trajectory and a mode schedule. The transmitter mode scheduler change transmitter odes based upon time or slant range.
    • Receiver Platform's trajectory
  • Path and file name
    • Receiver Reference Antenna
  • XYZ position, azimuth & elevation orientation, and antenna polarization for multiple antennae

    • The Model Generates 4 Output Files:

  • CSV Coarse Data File Used for Independent Analysis / Plotting Contains:
  • Position and Velocity Vectors for Each Antenna
  • Range and Range-rate of the Transmitter(s) Relative to Each Antenna
  • Received Power at Each Antenna
  • Sensed Frequency (Doppler) and Doppler-Rate at Each Antenna, and
  • Azimuth and elevation angles-of-arrival at each antenna.
  • Output Pulse File Data, for Each Pulse:
  • The Pulse Transmit Time
  • For Each Antenna
  • TOA
  • Position and Velocity Vector at the TOA
  • Received Power at the TOA
  • Doppler and Doppler-Rate at the TO
  • Azimuth and Elevation Angles at the TOA
  • TOA Error
  • TDOA File Data, For Each Pulse
  • Transmit Time
  • A Pulse ID
  • TOA at the reference antenna
  • TDOA of Each Antenna Relative to a Referenced Antenna Defined in the Configuration File
  • Keysight PDW Files in UXG Format 1 Format. Refer to Keysight Manuals

    • Request the User's Manual for Detailed Information


    Note: Things Change Rapidly! Specifications, Capabilities, Features and Availability Subject to Change Without Notice and May Be Restricted to Certain Users.