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Summary: we perform consultancy and contract work in areas such as telecommunications and audio that can be implemented by DSP in microprocessors. Such work can involve:

• software implementations involving specific DSP systems
• DSP algorithm development from more general specifications
• command interface DSP software
• outline DSP hardware design and advice
• general consultancy in areas of DSP

• educational eg presentations, seminars

Our abilities can be categorised as follows:

Skills: we are capable of realising complex DSP algorithms from scratch. The DSP code suites for the modem data pumps described in the data sheets on this website have all been developed from a "blank sheet of paper", given the transmitter-only descriptions in the ITU Standards. In particular, the V.34 implementation contains signal processing and DSP software elements far more complex than most DSP systems require. There are a number of innovative features in the code modules generally.

Software: we are equally adept at programming in assembler and C. Assembler tends to maximise DSP capabilities by achieving minimum resource usage and thus unit processor cost. With C, code portability across different processor makes and ranges is ensured whilst resource usage is still good because of the improved efficiency of modern C compilers. Code readability is always a paramount aim, together with the design of simple but highly flexible code interfaces.

Technology: as well as the code suites and utilities detailed elsewhere on this website, we have an in-house library of DSP software algorithms including:

• FFT kernels; PCM A- and µ-law transcoders; phase-to-cos/sin, dBs-to-linear, linear-to-dBs converters; maths functions such as square-root and magnitude conversion; digital filtering; tone generation and detection; telephone call progress generation & monitoring; command-line-interpreter for ASCII character sets eg AT commands

Experience: we have used DSP microprocessors since 1982. Our background includes: realising modem and general data transmission systems; audio systems for telecoms eg speech coders, acoustic echo cancellers; general signal generation and detection. We have been extensively involved in telecoms systems of which the DSP side is but one component part, so we can bring much "overview" input to bear in a design. We have working experience of mobile and wireless systems, and the time-division-multiplexed aspects of digital telephone exchanges.

Academic and professional contacts: we have excellent contacts with the electrical engineering research departments of Imperial College (London University) and Bristol University, so we are capable of acting as intermediaries to initiate and monitor university research work for clients. We regularly attend ITU and other standards forums.