Performance analysis of general pilot-aided linear channel estimation in LTE OFDMA systems with application to simplified MMSE schemes

Omar, Shahmeer; Ancora, Andrea; Slock, Dirk

doi:10.1109/pimrc.2008.4699619

Cited by 62 publications

(27 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It assumes perfect knowledge of the actual channel statistics and estimation is done for a frequency selective channel. [6] deals with estimation of LTE downlink channel for LS, MMSE, and Modified MMSE.…”

Section: Introductionmentioning

confidence: 99%

Performance analysis of pilot aided channel estimation methods for LTE system in time-selective channels

Rajeswari¹,

Sangeetha²,

Natchammai³

et al. 2010

2010 5th International Conference on Industrial and Information Systems

View full text Add to dashboard Cite

This paper deals with the performance analysis of channel estimation methods for LTE downlink system over time varying mobile environments. The analysis of channel estimation in the presence of interference is also done. Least square frequency domain (LS_Freq), least square time domain (LS_Time), maximum likelihood (ML) and minimum mean square error estimation (MMSE) techniques are focused for different bandwidth by varying the number of resource blocks used in OFDM structure of LTE system. As number of pilots increases with increasing bandwidth, performance of the estimator increases. Computer simulations are used in the comparisons. Linear Interpolation is performed to get the channel estimation of data symbols. Theoretical results are derived for LS_Time and ML techniques. MMSE performs well at low SNR. LS_Time and ML performs well at high SNR as they use the knowledge of number of channel taps.We achieve interference mitigation using channel estimation using repeated interference features obtained from the two types of pilot symbols used with different pilot density. This technique not only makes the channel estimation robust to the timeselectivity of the channel but also reduces the number of pilot subcarriers needed to estimate the channel.

show abstract

Section: Introductionmentioning

confidence: 99%

Performance analysis of pilot aided channel estimation methods for LTE system in time-selective channels

Rajeswari¹,

Sangeetha²,

Natchammai³

et al. 2010

2010 5th International Conference on Industrial and Information Systems

View full text Add to dashboard Cite

show abstract

“…The matrix notation of (1) is given by: where A −1 denotes the matrix inverse. The estimates for the channel coefficients at non-pilot subcarriers can then be easily obtained by interpolation [10]. However, when the channel is fast fading (i.e., high user velocity), the pilot symbols spacing may not be sufficient to enable proper tracking of the channel variations.…”

Section: ) Ls Channel Estimatormentioning

confidence: 99%

Context-Aware Cognitive SIMO Transceiver for Increased LTE-Downlink Link-Level Throughput

Mrissa

Bellili

Affes

et al. 2015

2015 IEEE International Conference on Ubiquitous Wireless Broadband (ICUWB)

View full text Add to dashboard Cite

Coherent detection requires accurate channel estimation to provide the high data rates promised by the LTE standard. However, for high-speed wireless data transmission services, channel estimation becomes a challenging task when the pilot insertion rate becomes insufficient to allow proper tracking of the channel variation. In this paper, we design a new singleinput multiple-output (SIMO) context-aware cognitive transceiver (CTR) that is able to switch to the best performing modem (modulation-demodulation) in terms of link-level throughput. For that purpose, on the top of conventional adaptive modulation and coding, we allow the context-aware CTR to make best selection among three different pilot-utilization modes: Conventional DataAided (DA) or pilot-assisted, Non-Data-Aided (NDA) or blind and Non-Data-Aided with pilot (NDA w. pilot) which is a newly proposed hybrid version between the DA and NDA modes. We also enable the CTR to make best selection between two different channel identification schemes: conventional Least Squares (LS)-type and newly developed Maximum Likelihood (ML) estimators. Depending on whether pilot symbols are used or not, we further enable the CTR to make best selection among two data detection modes: coherent or differential. Owing to extensive and exhaustive LTE-downlink link-level simulations, we are able to draw out the decision rules of the new CTR that identify the best combination triplet of pilot-use, channel-identification, and datadetection modes. The latter is able to achieve the best link-level performance against any given operating conditions in terms of channel type, mobile speed, SNR, and Channel Quality Indicator (CQI). Significant link-level throughput gains of the new proposed CTR against the conventional one (i.e., pilot-assisted LS-type channel estimation with coherent detection) can be achieved in most operating conditions and could reach as much as 700% at low SNR and high mobility!

show abstract

“…To deal with this problem, RLS algorithm [6] is introduced. The second scenario is that: virtual subcarriers are applied in OFDM system, and RLS algorithm is used for channel estimation.…”

Section: A Two Scenarios Studied In This Papermentioning

confidence: 99%

Pilot tone selection in OFDM amplified-and-forward relay system

Chen

2011

2011 International Conference on Wireless Communications and Signal Processing (WCSP)

View full text Add to dashboard Cite

Abstract-Channel estimation for OFDM amplify-and-forward relay system requires transmission of pilot tones in source node, and different pilot tones can be derived according to different channel estimation algorithms and OFDM scenarios. This paper derives two different pilot tones with different scenarios: 1) no virtual subcarrier is applied in OFDM system and LS algorithm is used in channel estimation; 2) virtual subcarriers are applied in OFDM system and RLS algorithm is used in channel estimation.

show abstract

Performance analysis of general pilot-aided linear channel estimation in LTE OFDMA systems with application to simplified MMSE schemes

Cited by 62 publications

References 5 publications

Performance analysis of pilot aided channel estimation methods for LTE system in time-selective channels

Performance analysis of pilot aided channel estimation methods for LTE system in time-selective channels

Context-Aware Cognitive SIMO Transceiver for Increased LTE-Downlink Link-Level Throughput

Pilot tone selection in OFDM amplified-and-forward relay system

Contact Info

Product

Resources

About