Characterization of an empirically-derived database of time-varying microwave channel responses

Abstract

This paper reports on the gathering, processing, and categorization of empirically derived time-varying channel responses. The passband data and datu collection information is provided courtesy of Applied Signal Technology (Sunnyvale, CA). It is the intent of this paper to provide the signal processing community with a database of timevarying fractionally-spaced channel responses and received sequences based on empirical measurements which can be used to test and refine existing time-varying channel models and also propose new ones.

Performance analysis of Godard-based blind channel identification

“…2 Recall that and were defined in Section II-A. The operator is a generalization of an -shifted version of from (5) and is employed so that our bound applies to both finite and infinite-dimensional channels and equalizers. When are FIR, reduces to a block Toeplitz matrix, and specifies its largest singular value.…”

“…Zeroing the partial derivative of (16) with respect to , it is straightforward to show that The quantity above vanishes unless the indices and are suitably aligned. After a bit of algebra, 5 we have the equation at the bottom of the page, where the last term only appears in the real-valued case. Generalizing the previous expression to the case and combining the result with (31)-(33), we arrive at (30).…”

“…The identification algorithm could be used "off-line" during such a design phase to yield channel estimates with guaranteed performance. In addition, the tracking capabilities of the algorithm would allow a study of channel time-variations (e.g., [5]). Perhaps more interesting are "on-line" applications, where the proposed identification algorithm would be used in an operating receiver.…”