LTPDA Toolbox™

contents

Version 2.0 LTPDA Toolbox Software

This table summarizes what's new in Version 2.0:

• Introduction
• New toolbox features and changes

Introduction

There has been a significant amount of work done since V1.9.3.

New toolbox features and changes

The highlights are:

• A new Graphical Programming interface for the construction of signal processing pipelines (LTPDAworkbench)
• New data whitening methods are included, ao/whiten1D and ao/whiten2D.
• Most methods of the AO class should now support multiple outputs, in addition to the vector output. For example, the following are supported:
  • a = lpsd(b1,b2,b3)
  • [a1,a2,a3] = lpsd(b1,b2,b3)
• Model fitting tools:
  • curvefit for doing non-linear least-squares, now including weights
  • lscov for doing linear least-squares fitting
  • straightLineFit is a wrapper of lscov for fitting data with a straight-line
• Operators, +-.*./*/, all conform to more standard MATLAB type behaviour. For example, adding a single AO to a vector of AOs results in a vector of AOs where the single AO is added to each element of the vector.
• Digital filtering with IIR filters now has two possible ways of applying a bank of filters. By specifying the ‘bank’ parameter, the filters will be applied as a ‘serial’ bank or a ‘parallel’ bank.
• Two new noise-generators are included, noisegen1D and noisegen2D (which can produce correlated data streams).
• AOs can now be built from a set of built-in models. Users can also write their own models and point LTPDA to a directory (or more than one) containing those model files.
• The user preferences of LTPDA are now controlled via a graphical user interface. To adjust the user preferences, run LTPDAprefs.
• Two new transfer function representations are present as user classes of this version of the toolbox. The class parfrac allows the user to build transfer function models that are a series of partial fractions; the class rational allows the user to build a transfer function as a rational polynomial in s. Some converters also exist to go between these and the existing transfer function models, pzmodel (pole/zero models), miir (IIR filters) and ssm (state-space models).
• A new method, ao/heterodyne, to heterodyne data at a given frequency.
• All transfer function representations and digital filters now can be assigned input and output units. This means that units are now propagated through fully through any analysis.
• A new rebuild method to rebuild objects from their self-contained history trees.
• New graphical user interfaces
  • modelViewer - a viewer for the built-in ao and ssm models
  • constructor - a helper for writing object constructors (rewritten)
• New convenient AO methods to apply gain and to add an offset to data (scale, offset).
• Transfer function estimators now return error terms in the procinfo field of the result ao.
• Units are not automatically simplified. Instead the user can now do that on demand with the simplifyYunits method. There are also methods to convert between Hz and s: HzToS and sToHz.
• Digital IIR filters are now initialised to a state based on the input data. This should reduce start-up transients.
• Data in AOs can be converted from one type to another using the new ao/convert method.
• Pole/zero models (pzmodel) now support a delay parameter.

Version 2.0.1 LTPDA Toolbox Software

Getting Started with the LTPDA Toolbox

©LTP Team