A new MMSE channel estimation algorithm for OFDM systems

Kinjo, Shigenori

doi:10.1587/elex.5.738

Cited by 7 publications

(6 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To present the mathematic features of the wireless channels, slow and fast CSIs are used to denote the CSIs that are known under slow fading and fast fading, respectively. In some other cases, the CSI is blind for both transmitter and receiver; this is usually called unknown CSI, such as in .…”

Section: System Modelmentioning

confidence: 99%

See 1 more Smart Citation

Optimal power scheduling in 802.11n wireless networks for real‐time services

Deng

Chen

Ren

et al. 2012

Wireless Communications

View full text Add to dashboard Cite

The growing popularity of mobile devices in our daily life demands higher throughput of wireless networks. The new communication standard 802.11n has significantly improved throughput because of the use of advanced technologies such as the multiple-input multiple-output communication technique. Because mobile devices are usually battery-operated, power efficiency is critical; on the other hand, delay performance can be improved by transmitting at high power. To address the conflicting requirement of power saving and small delay, power scheduling is needed. In the past, many approaches to power scheduling have been proposed for real-time applications, but few of them have considered complicated modes of channel state information(CSI) in multiple-input multiple-output. In this paper, we study this and classify the CSI into four types, namely, constant, slow fading, fast fading, and unknown. For known CSI, we propose an optimal algorithm for power scheduling. For unknown CSI, we propose an approximate algorithm based on some heuristics. To improve resource utilization, a stochastic delay-bound method is proposed for fast-fading condition. Simulation results demonstrate that the performance achieved by the optimal and heuristic algorithms agrees well with the analysis.

show abstract

Section: System Modelmentioning

confidence: 99%

“…It has advantages in that it has no overhead loss. There exist many related approaches such as . Thus, the optimal power scheduling can be reached by applying some estimation algorithms to figure out the channel at first.…”

Section: Unknown Channel State Informationmentioning

confidence: 99%

Optimal power scheduling in 802.11n wireless networks for real‐time services

Deng

Chen

Ren

et al. 2012

Wireless Communications

View full text Add to dashboard Cite

show abstract

“…It has been shown that even a little amount of phase noise significantly reduces OFDM performance. As a result, the effects of phase noise on OFDM systems must be researched, and mitigation techniques must be created [4].…”

Section: Introductionmentioning

confidence: 99%

A New Ml-Mmse Equalizer Using Technique for Mitigating Wave Disturbances in Ofdm Systems

2023

IRJMETS

View full text Add to dashboard Cite

MIMO systems, which offer a broad coverage, high throughput, and dependable services by enabling spatial dimension and by taking into account various numbers of transmitter and receiver antennas, are one of the approaches to overcome the many obstacles in wireless communication systems. In order to reduce wave disturbances in OFDM systems, a novel ML-MMSE equalizer approach is proposed in this study. On the transmitter side, encoders and decoders are used to convert the digital signal to an analogue signal, and on the reception side, they are used to convert the analogue signal to a digital signal. To transmit information, quadrature phase shift keying modulators adjust the amplitude and frequency of a carrier signal. The modulated signals are demodulated using an IDFT approach. As a channel model, AWGN is frequently employed. Digital communication systems employ the MMSE equalizer to lessen the impact of noise and mistakes. The performance of ML is superior to other schemes when the MMSE and ML equalizers are applied to the AWCN channel. A signal that was modulated using the quadrature phase shift keying technique is demodulated by the QPSK Demodulator Block. A scalar or column-vector input signal is accepted by this block. The approach was used since the trial was successful and might potentially lead to improvements. The MATLAB program is used to carry out this system.

show abstract

“…Most flavors of the channel estimation techniques discussed in the literature are done in the frequency domain, using pilot symbols at regular intervals in the time/frequency grid [32]- [36]. Iterative joint channel estimation and multi-user detection for multi-antenna OFDM is discussed in [37].…”

Section: Introductionmentioning

confidence: 99%

Coherent Detection of Turbo-Coded OFDM Signals Transmitted Through Frequency Selective Rayleigh Fading Channels with Receiver Diversity and Increased Throughput

Vasudevan

2015

Wireless Pers Commun

View full text Add to dashboard Cite

In this work, we discuss techniques for coherently detecting turbo coded orthogonal frequency division multiplexed (OFDM) signals, transmitted through frequency selective Rayleigh (the magnitude of each channel tap is Rayleigh distributed) fading channels having a uniform power delay profile. The channel output is further distorted by a carrier frequency and phase offset, besides additive white Gaussian noise (AWGN). A new frame structure for OFDM, consisting of a known preamble, cyclic prefix, data and known postamble is proposed, which has a higher throughput compared to the earlier work. A robust turbo decoder is proposed, which functions effectively over a wide range of signal-to-noise ratio (SNR). Simulation results show that it is possible to achieve a bit-error-rate (BER) of 10 −5 at an SNR per bit as low as 8 dB and throughput of 82.84%, using a single transmit and two receive antennas. We also demonstrate that the practical coherent receiver requires just about 1 dB more power compared to that of an ideal coherent receiver, to attain a BER of 10 −5 . The key contribution to the good performance of the practical coherent receiver is due to the use of a long preamble (512 QPSK symbols), which is perhaps not specified in any of the current wireless communication standards. We have also shown from computer simulations that, it is possible to obtain even better BER performance, using a better code. A simple and approximate Cramér-Rao bound on the variance of the frequency offset estimation error for coherent detection, is derived. The proposed algorithms are well suited for implementation on a DSP-platform.

show abstract

A new MMSE channel estimation algorithm for OFDM systems

Cited by 7 publications

References 5 publications

Optimal power scheduling in 802.11n wireless networks for real‐time services

Optimal power scheduling in 802.11n wireless networks for real‐time services

A New Ml-Mmse Equalizer Using Technique for Mitigating Wave Disturbances in Ofdm Systems

Coherent Detection of Turbo-Coded OFDM Signals Transmitted Through Frequency Selective Rayleigh Fading Channels with Receiver Diversity and Increased Throughput

Contact Info

Product

Resources

About