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Showing posts with the label Superimposed pilot

Understanding Hierarchical Modulations, what is interlayer interference and how to quantify it: II Effective Signal-to-Noise Ratio (ESNR)

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[Understanding Hierarchical Modulations: I Introduction] [Understanding Hierarchical Modulations: III Modulation Efficiency] S. Wang and B. K. Yi, "Optimizing Enhanced Hierarchical Modulations," IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference, New Orleans, LO, 2008, pp. 1-5 [How to Broadcast Multimedia Contents? II Lessons from The Channel] [How to Broadcast Multimedia Contents? IV Hierarchical Modulation] [How to Broadcast Multimedia Contents? V Overloaded Transmission and IC] [How to Broadcast Multimedia Contents? VI Open-Loop MIMO for BCMCS] [How to Broadcast Multimedia Contents? VII Network Layer or Steam Layer Design] Besides the throughputs achievable by hierarchical modulations, it is also interesting to understand hierarchical modulations from a practical signal-processing perspective. At this time, the performance of hierarchical modulation will be evaluated through an actual implementation, where demodulation error is one of the ...

Understanding Hierarchical Modulations, what is interlayer interference and how to quantify it: I Introduction

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[Understanding Hierarchical Modulations: II Effective SNR] [Understanding Hierarchical Modulations: III Modulation Efficiency] "Optimizing Enhanced Hierarchical Modulations," IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference, New Orleans, LO, 2008, pp. 1-5 [How to Broadcast Multimedia Contents? II Lessons from The Channel] [How to Broadcast Multimedia Contents? IV Hierarchical Modulation] [How to Broadcast Multimedia Contents? V Overloaded Transmission and IC] [How to Broadcast Multimedia Contents? VI Open-Loop MIMO for BCMCS] [How to Broadcast Multimedia Contents? VII Network Layer or Steam Layer Design] Hierarchical modulation, also called layered modulation, is one of the techniques for multiplexing multiple data streams and modulating them into one single symbol stream, where the base-layer symbols and enhancement-layer symbols are superimposed before being transmitted. When hierarchically modulated signals are transmitted, users with good...

How Much Feedback Is Enough for MIMO? II Channel Estimation

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[How Much Feedback Is Enough for MIMO? I Introduction] [How Much Feedback Is Enough for MIMO? III Codebook Design] [How Much Feedback Is Enough for MIMO? IV Channel Quantization] [How Much Feedback Is Enough for MIMO? V Feedback Reliabilities] [How Much Feedback Is Enough for MIMO? VI Rank Deficiency] MIMO beamforming with finite-rate feedback is modelled as a noisy Gaussian binary erasure feedback channel depicted. In reality, the receivers estimate channels with the pilots sent by transmitter. Accuracy of the channel estimation depends on both forwardlink design and receiver design. The pilot transmission is important for receiver to efficiently estimate CSI. antenna. An overview of pilot-assisted transmission (PAT) including pilot placement and channel estimation can be found in [Tong 04]. There are two popular pilot patterns, time multiplexed pilots (TMP)  and superimposed pilots (SIP), ...