Packet-level network simulators such as ns-3 require accurate physical (PHY) layer models for packet error rate (PER) for wideband transmission over fading wireless channels. To manage complexity and achieve practical runtimes, suitable link-to-system mappings can convert high fidelity PHY layer models for use by packet-level simulators. This work reports on two new contributions to the ns-3 Wi-Fi module, which presently only contains error models for Single Input Single Output (SISO), additive white Gaussian noise (AWGN) channels. To improve this, a complete implementation of a link-to-system mapping technique for IEEE 802.11 TGn fading channels is presented that involves a method for efficient generation of channel realizations within ns-3. The runtimes for the prior method suffers from scalability issues with increasing dimensionality of Multiple Input Multiple Output (MIMO) systems. We next propose a novel method to directly characterize the probability distribution of the"effective SNR" in link-to-system mapping. This approach is shown to require modest storage and not only reduces ns-3 runtime, it is also insensitive to growth of MIMO dimensionality. We describe the principles of this new method and provide details about its implementation, performance, and validation in ns-3.
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Efficient Link-to-System Mappings for MU-MIMO Channel D Scenarios in 802.11ac WLANs
Results are presented from an extensive campaign of link simulations for multi-user multi-input multi-output (MU-MIMO) scenarios of 802.11ac wireless local area networks (WLAN) for use within a link-to-system mapping framework for ns-3 network simulation. As in [2], Exponential Effective SNR Mapping (EESM) is used inclusive of the impact of channel estimation, but this works extends beyond SISO to MU-MIMO. MATLAB® link simulation results using the WLAN Toolbox™ are used to generate an error rate table lookup for EESM to produce a corresponding packet error rate (PER) for use by ns-3. The simulation programs are made available to allow reproduction and extending of the baseline results.
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- Award ID(s):
- 1836725
- PAR ID:
- 10120304
- Date Published:
- Journal Name:
- WNGW 2019 Proc. Workshop on Next-Gen Wireless for ns-3
- Page Range / eLocation ID:
- 18 to 21
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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