We investigate the multi-faceted access point (AP) placement problems in uplink small-cell and cell-free networks in the context of throughput-optimality and to what extent the popular Lloyd algorithm from vector quantization (VQ) is suited to solve them. We develop single user throughput optimization formulations and solutions related to VQ considering the small cell scenario, after which we expand the formulations to multiple users. For the cell-free scenario, we consider the mean throughput of all users and a max-min technique. We compare the rate performances of the AP placement solutions from both scenarios with the Lloyd algorithm. While the Lloyd algorithm is found not to strictly solve for small cell AP locations and its approach is divergent from the cell-free perspective, we conclude from numerical experiments that it is good enough for both scenarios.
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Modified Vector Quantization for Small-Cell Access Point Placement with Inter-Cell Interference
In this paper, we explore the small-cell uplink access point (AP) placement problem in the context of throughput optimality and provide solutions while taking into consideration inter-cell interference (ICI). First, we briefly review the vector quantization (VQ) approach and related single user throughput optimal formulations for AP placement. Then, we investigate the small-cell case with multiple users and expose the limitations of mean squared error based VQ for solving this problem. While the Lloyd algorithm from the VQ approach is found not to strictly solve the small-cell case, based on the tractability and quality of the resulting AP placement, we deem it suitable as a simple and appropriate framework to solve more complicated problems. Accordingly, to minimize ICI and consequently enhance achievable throughput, we design two Lloyd-type algorithms, namely the Interference Lloyd algorithm and the Inter-AP Lloyd algorithm, both of which incorporate ICI in their distortion functions. Simulation results show that both of the proposed algorithms provide superior 95%-likely rate over the traditional Lloyd algorithm and the Inter-AP Lloyd algorithm yields a significant increase of up to 36.34% in achievable rate over the Lloyd algorithm.
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- Award ID(s):
- 2124929
- NSF-PAR ID:
- 10332328
- Date Published:
- Journal Name:
- IEEE Transactions on Wireless Communications
- ISSN:
- 1536-1276
- Page Range / eLocation ID:
- 1 to 15
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/TWC.2022.3148996
