Software design for CSP.LMC in SKA

Abstract

The Square Kilometer Array (SKA) is devoted to the construction of a two body giant Radio-telescope. The design and implementation of the SKA Monitor and Control software involves about 100 people referring to eight Agile Teams developing different software elements of the telescope. Each of these elements is implemented as a 'device' within the TANGO Control System framework, written in Python code. This paper analyzes the implemented design of the Local Monitoring and Control (LMC) of the Central Signal Processor (CSP), from now on called CSP.LMC. CSP is the SKA element that will make the data that comes from the antennas available for scientific analysis. It is composed of different data processing components, i.e. the Correlator and Beam Former, the Pulsar Search and the Pulsar Timing. In this larger system, CSP.LMC has the role to communicate with the Telescope Manager (TM), i. e. the software front-end for operations, as if the CSP was an unique entity. The paper shows the detailed structure of the software, implemented with an Object Oriented approach, with a design largely inspired by some standard design patterns, such as the Observer, the Command and the Aggregator. Another essential feature is the separation of the business logic from the TANGO communication layer, improving the testability and the maintainability of the code.