Suprema of Chaos Processes and the Restricted Isometry Property
نویسندگان
چکیده
We present a new bound for suprema of a special type of chaos processes indexed by a set of matrices, which is based on a chaining method. As applications we show significantly improved estimates for the restricted isometry constants of partial random circulant matrices and time-frequency structured random matrices. In both cases the required condition on the number m of rows in terms of the sparsity s and the vector length n is m & s log s log n.
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ورودعنوان ژورنال:
- CoRR
دوره abs/1207.0235 شماره
صفحات -
تاریخ انتشار 2012