Angle-preserving Quantized Phase Embeddings
نویسنده
چکیده
We demonstrate that the phase of randomized complex-valued projections of real-valued signals preserves information about the angle, i.e., the correlation, between those signals. This information can be exploited to design quantized angle-preserving embeddings, which represent such correlations using a finite bit-rate. The proposed embeddings generalize known results on binary embeddings and 1-bit compressive sensing and allow us to explore the trade-off between number of measurements and number of bits per measurement, given the bit rate. The freedom provided by this trade-off, which has also been observed in quantized Johnson-Lindenstrauss embeddings, can improve performance at reduced rate in a number of applications.
منابع مشابه
On Embedding the Angles Between Signals
The phase of randomized complex-valued projections of real signals preserves information about the angle, i.e., the correlation, between signals. This information can be exploited to design angle preserving embeddings, which represent such correlations. These embeddings generalize known results on binary embeddings and 1-bit compressive sensing and reduce the embedding uncertainty. 2013 Signal ...
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