Interference-Aware Accurate Signal Recovery in Sub-1 GHz UHF Band Reuse-1 Cellular OFDMA Downlinks
Reuse-1 systems operating in the sub-1 GHz UHF band are limited by substantial co-channel interference (CCI). In such orthogonal frequency division multiple access (OFDMA) cellular systems, the inter-sector or inter-tower interference (ITI) makes accurate signal recovery quite challenging as sub-1 G...
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| Format: | Article |
| Language: | English |
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IEEE
2022-01-01
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| Series: | IEEE Open Journal of the Communications Society |
| Subjects: | |
| Online Access: | https://ieeexplore.ieee.org/document/9939169/ |
| _version_ | 1811221284312317952 |
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| author | M. V. Abhay Mohan K. Giridhar |
| author_facet | M. V. Abhay Mohan K. Giridhar |
| author_sort | M. V. Abhay Mohan |
| collection | DOAJ |
| description | Reuse-1 systems operating in the sub-1 GHz UHF band are limited by substantial co-channel interference (CCI). In such orthogonal frequency division multiple access (OFDMA) cellular systems, the inter-sector or inter-tower interference (ITI) makes accurate signal recovery quite challenging as sub-1 GHz bands only support single-input single-output (SISO) links. Interference-aware receiver algorithms are essential to mitigate the ITI in such low-frequency bands. Such algorithms enable ubiquitous mobile broadband access over the entire homeland, say with >95% geographical coverage with quality of service guarantees. One element of the interference-aware signal recovery is the least-squares-based joint channel estimation scheme that uses non-orthogonal pilot subcarriers. This estimator is then compared with a variant that uses orthogonal pilot subcarriers to bring out the advantage of this joint estimator. It is shown that the proposed joint estimator requires fewer pilots to be well-determined when compared to its under-determined orthogonal counterpart. Moreover, it is easy to implement and does not require any knowledge of channel statistics. This work also derives a compensation factor needed for the interference-aware detector in the presence of inter-carrier interference (ICI) originating from multiple transmitters. Simulation results show that the proposed joint channel estimator outperforms traditional estimators at moderate to high frequency selectivity. The proposed compensation factor to the joint detector is found to be essential for recovering the transmitted signal in the absence of phase-tracking pilots. |
| first_indexed | 2024-04-12T07:56:42Z |
| format | Article |
| id | doaj.art-9ed3ccb888134377a211748a9ae92d72 |
| institution | Directory Open Access Journal |
| issn | 2644-125X |
| language | English |
| last_indexed | 2024-04-12T07:56:42Z |
| publishDate | 2022-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Open Journal of the Communications Society |
| spelling | doaj.art-9ed3ccb888134377a211748a9ae92d722022-12-22T03:41:28ZengIEEEIEEE Open Journal of the Communications Society2644-125X2022-01-0132087210510.1109/OJCOMS.2022.32195579939169Interference-Aware Accurate Signal Recovery in Sub-1 GHz UHF Band Reuse-1 Cellular OFDMA DownlinksM. V. Abhay Mohan0https://orcid.org/0000-0002-9290-9929K. Giridhar1Department of Electrical Engineering, Indian Institute of Technology Madras, Chennai, IndiaDepartment of Electrical Engineering, Indian Institute of Technology Madras, Chennai, IndiaReuse-1 systems operating in the sub-1 GHz UHF band are limited by substantial co-channel interference (CCI). In such orthogonal frequency division multiple access (OFDMA) cellular systems, the inter-sector or inter-tower interference (ITI) makes accurate signal recovery quite challenging as sub-1 GHz bands only support single-input single-output (SISO) links. Interference-aware receiver algorithms are essential to mitigate the ITI in such low-frequency bands. Such algorithms enable ubiquitous mobile broadband access over the entire homeland, say with >95% geographical coverage with quality of service guarantees. One element of the interference-aware signal recovery is the least-squares-based joint channel estimation scheme that uses non-orthogonal pilot subcarriers. This estimator is then compared with a variant that uses orthogonal pilot subcarriers to bring out the advantage of this joint estimator. It is shown that the proposed joint estimator requires fewer pilots to be well-determined when compared to its under-determined orthogonal counterpart. Moreover, it is easy to implement and does not require any knowledge of channel statistics. This work also derives a compensation factor needed for the interference-aware detector in the presence of inter-carrier interference (ICI) originating from multiple transmitters. Simulation results show that the proposed joint channel estimator outperforms traditional estimators at moderate to high frequency selectivity. The proposed compensation factor to the joint detector is found to be essential for recovering the transmitted signal in the absence of phase-tracking pilots.https://ieeexplore.ieee.org/document/9939169/Carrier frequency offset compensationinter-carrier interferenceinterference-aware receiversinter-tower interferencejoint channel estimationjoint detection |
| spellingShingle | M. V. Abhay Mohan K. Giridhar Interference-Aware Accurate Signal Recovery in Sub-1 GHz UHF Band Reuse-1 Cellular OFDMA Downlinks IEEE Open Journal of the Communications Society Carrier frequency offset compensation inter-carrier interference interference-aware receivers inter-tower interference joint channel estimation joint detection |
| title | Interference-Aware Accurate Signal Recovery in Sub-1 GHz UHF Band Reuse-1 Cellular OFDMA Downlinks |
| title_full | Interference-Aware Accurate Signal Recovery in Sub-1 GHz UHF Band Reuse-1 Cellular OFDMA Downlinks |
| title_fullStr | Interference-Aware Accurate Signal Recovery in Sub-1 GHz UHF Band Reuse-1 Cellular OFDMA Downlinks |
| title_full_unstemmed | Interference-Aware Accurate Signal Recovery in Sub-1 GHz UHF Band Reuse-1 Cellular OFDMA Downlinks |
| title_short | Interference-Aware Accurate Signal Recovery in Sub-1 GHz UHF Band Reuse-1 Cellular OFDMA Downlinks |
| title_sort | interference aware accurate signal recovery in sub 1 ghz uhf band reuse 1 cellular ofdma downlinks |
| topic | Carrier frequency offset compensation inter-carrier interference interference-aware receivers inter-tower interference joint channel estimation joint detection |
| url | https://ieeexplore.ieee.org/document/9939169/ |
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