A distributed acquisition apparatus, comprising: a sampler component configured to receive a signal under test; a plurality of analog-to-digital converters ADCs operationally coupled to the sampler component and configured to produce digitized samples of the signal under test; a time-interleaved acquisition processing network including a plurality of interconnected distributed acquisition components, each distributed acquisition component including: an acquisition memory configured to store a portion of the digitized samples; and one or more summers configured to de-interleave the digitized samples between the distributed acquisition components; and a last distributed acquisition component associated with the interleaved processing network of distributed acquisition components, the last distributed acquisition component including an acquisition memory to store a portion of the digitized samples and one or more summers configured to de-interleave the digitized samples, wherein the last distributed acquisition component is configured to receive the de-interleaved digitized samples from the plurality of distributed acquisition components and output a recombined coherent waveform; characterised in that each of the distributed acquisition components includes: a mixer component coupled to an input of the corresponding acquisition memory, and configured to receive and multiply the corresponding portion of the digitized samples with a complex sinusoidal waveform, and to produce a mixed signal having mathematical real and imaginary parts; a polyphase interpolation filter coupled to an output of the acquisition memory and configured to receive and filter the mixed signal; and one or more down-samplers coupled to the corresponding polyphase interpolation filter and configured to down-sample the filtered signal. a sampler component configured to receive a signal under test; a plurality of analog-to-digital converters ADCs operationally coupled to the sampler component and configured to produce digitized samples of the signal under test; a time-interleaved acquisition processing network including a plurality of interconnected distributed acquisition components, each distributed acquisition component including: an acquisition memory configured to store a portion of the digitized samples; and one or more summers configured to de-interleave the digitized samples between the distributed acquisition components; and an acquisition memory configured to store a portion of the digitized samples; and one or more summers configured to de-interleave the digitized samples between the distributed acquisition components; and a last distributed acquisition component associated with the interleaved processing network of distributed acquisition components, the last distributed acquisition component including an acquisition memory to store a portion of the digitized samples and one or more summers configured to de-interleave the digitized samples, wherein the last distributed acquisition component is configured to receive the de-interleaved digitized samples from the plurality of distributed acquisition components and output a recombined coherent waveform; characterised in that each of the distributed acquisition components includes: a mixer component coupled to an input of the corresponding acquisition memory, and configured to receive and multiply the corresponding portion of the digitized samples with a complex sinusoidal waveform, and to produce a mixed signal having mathematical real and imaginary parts; a polyphase interpolation filter coupled to an output of the acquisition memory and configured to receive and filter the mixed signal; and one or more down-samplers coupled to the corresponding polyphase interpolation filter and configured to down-sample the filtered signal. a mixer component coupled to an input of the corresponding acquisition memory, and configured to receive and multiply the corresponding portion of the digitized samples with a complex sinusoidal waveform, and to produce a mixed signal having mathematical real and imaginary parts; a polyphase interpolation filter coupled to an output of the acquisition memory and configured to receive and filter the mixed signal; and one or more down-samplers coupled to the corresponding polyphase interpolation filter and configured to down-sample the filtered signal.