An enhancement that improves the performance of test and measurement equipment such as digital oscilloscopes and arbitrary waveform generators through the use of compression and decompression is described. The present invention is particularly effective for compressing and decompressing high-speed, bandlimited analog signals that are not appropriately or cannot effectively be compressed by prior art speech, audio, image, and video compression algorithms due to various limitations of such prior art compression solutions. The present invention improves digital oscilloscopes by compressing the sampled version of an analog waveform under observation in real time, allowing a significantly longer duration of the waveform to be stored in the
oscilloscope's capture memory, when compared with the duration of the same
signal's uncompressed waveform stored in the same memory. Similarly, the present invention improves arbitrary waveform generators by storing a compressed version of a desired arbitrary waveform, instead of the uncompressed version of the arbitrary waveform, in the
signal generator's waveform memory. During
signal generation, the compressed waveform is decompressed in real time. The uncompressed waveform drives a D / A converter that generates the desired analog waveform. The present invention's simplicity, and its ability to be implemented using
parallel compression and decompression elements, allows its use at the high sampling rates of test and measurement instruments. Using the present invention, storage elements in test and measurement equipment can hold significantly longer waveforms in a fixed amount of memory. Users of the present invention can also determine the proper balance between the fidelity and the duration of the decompressed waveform by adjusting various compression and decompression
control parameters.