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Full-Text Articles in Computer Engineering
Truncated Hyperbolic Mapping For Non-Binary Turbo Coding In Uwb, K. Popovski, Tadeusz Wysocki, B. J. Wysocki
Truncated Hyperbolic Mapping For Non-Binary Turbo Coding In Uwb, K. Popovski, Tadeusz Wysocki, B. J. Wysocki
Department of Electrical and Computer Engineering: Faculty Publications (to 2015)
The combination of user multiplexing and data encoding within Ultra Wideband systems has been proposed to improve bit error performance. Relative to conventional binary coding, this technique has shown to reduce error rates in scarcely populated systems. Where non-binary turbo coding modulates data to form an integer sequence, a random mapping is generally applied to develop a time hopping sequence. This paper explores the possibility of mapping through the application of truncated hyperbolic congruence codes. Comparative results against a random mapping indicate an improvement in system performance for higher turbo iteration levels in the receiver. Transceiver architecture is based upon …
Combined User Multiplexing And Data Modulation Through Non-Binary Turbo Codes For Uwb, K. Popovski, Tadeusz Wysocki, B. J. Wysocki
Combined User Multiplexing And Data Modulation Through Non-Binary Turbo Codes For Uwb, K. Popovski, Tadeusz Wysocki, B. J. Wysocki
Department of Electrical and Computer Engineering: Faculty Publications (to 2015)
With significant research being conducted in Ultra Wideband communications to increase error performance, this paper proposes a combination of user multiplexing and data encoding to achieve a BER improvement. Through the use of non-binary turbo coding, data is modulated to form a time hopping code which is applied to a time-reversed UWB system. Comparative results with conventional binary coding are given, showing the possibility for BER improvements in systems with a low number of users. Slight performance degradations for a large number of users exist. The effects of a user applying turbo coding on other users not applying forward error …
Closed-Form Derivations Of Isi And Mui For Time-Reversed Ultra Wideband, K. Popovski, Beata J. Wysocki, Tadeusz Wysocki
Closed-Form Derivations Of Isi And Mui For Time-Reversed Ultra Wideband, K. Popovski, Beata J. Wysocki, Tadeusz Wysocki
Department of Electrical and Computer Engineering: Faculty Publications (to 2015)
Through transmitter pre-filtering, a time reversed UWB system is capable if harnessing a multipath channel to achieve temporal and spatial focusing. Unfortunately, large RMS channel delay spread leads to significant intersymbol and multiuser interference. This paper presents closed-form expressions for self and multi-user interference for a UWB system utilizing a time-reversed approach. The influence of user multiplexing codes is taken to account through incorporation of a ‘separation probability’, which characterizes a family of hopping sequences. The standardized IEEE 802.15.3a channel model is applied, and the derived performances are compared with that of a simulated time hopped time-reversed UWB system.