Raptor code, a member of the rateless fountain codes family, has been a preferred technology for the forward error correction (FEC) at the application layer. It is used by the 3(rd) generationpartnershipprogram (3GP...
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ISBN:
(纸本)9781612848570
Raptor code, a member of the rateless fountain codes family, has been a preferred technology for the forward error correction (FEC) at the application layer. It is used by the 3(rd) generationpartnershipprogram (3GPP) Multimedia Broadcast/Multicast Service (MBMS) and Digital Video Broadcasting (DVB-H) standards for multimedia broadcast and content delivery. Currently, a next generation fountain code, called RaptorQ, is being proposed. It aims at reducing to a minimum the redundant FEC information, outperforming significantly Raptor code. The improved coding performance comes at the expense of increased encoding and decoding complexity. This paper compares the coding properties, the decoding performance and the energy efficiency of the two codes on embedded system. Furthermore, simulations are performed for a practical MBMS scenario. Finally, conclusions are drawn with respect to the applicability of the new code for realtime multimedia broadcasting and content delivery.
In this work an optimized approach of power control during soft handoff in downlink direction of WCDMA systems is proposed which is based on unbalanced power control scheme in which in the downlink direction all base ...
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ISBN:
(纸本)9781479976836
In this work an optimized approach of power control during soft handoff in downlink direction of WCDMA systems is proposed which is based on unbalanced power control scheme in which in the downlink direction all base stations in the active set transmit with different power to the MS based on the level of attenuation to the MS. Compared to balanced and unbalanced power control schemes adopted by 3rd generation partnership program (3GPP) in downlink direction proposed power control scheme during soft handoff reduces the additional interference caused by multiple site transmission and minimizes the overall transmitted power, thus increases the downlink capacity but compromises in the macro-diversity gain due to soft handoff. The proposed scheme is particularly suitable in the environments which face poor propagation attenuation.
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