Practical Implementation of Index Modulation-Based Waveforms

Gökçeli, Selahattin; Başar, Ertuğrul; Wen, Miaowen; Kurt, Güneş Karabulut

doi:10.1109/access.2017.2771200

“…First of all, from Fig. 2, it is obvious that the analytical and asymptotic expressions for average outage probability given in (14), (15) and (16) have been substantiated. The analytical results well match the numerical results, and the asymptotic results get increasingly close to the numerical results when P t /N 0 becomes large.…”

Section: A Verification Of Analysismentioning

confidence: 76%

Enhanced Orthogonal Frequency-Division Multiplexing With Subcarrier Number Modulation

Dang

¹

,

Ma

²

,

Shihada

³

et al. 2019

IEEE Internet Things J.

View full text Add to dashboard Cite

A novel modulation scheme termed orthogonal frequency-division multiplexing with subcarrier number modulation (OFDM-SNM) has been proposed and regarded as one of the promising candidate modulation schemes for next generation networks. Although OFDM-SNM is capable of having a higher spectral efficiency (SE) than OFDM with index modulation (OFDM-IM) and plain OFDM under certain conditions, its reliability is relatively inferior to these existing schemes, because the number of active subcarriers varies. In this regard, we propose an enhanced OFDM-SNM scheme in this paper, which utilizes the flexibility of placing subcarriers to harvest a coding gain in the high signal-to-noise ratio (SNR) region. In particular, we stipulate a methodology that optimizes the subcarrier activation pattern (SAP) by subcarrier assignment using instantaneous channel state information (CSI) and therefore the subcarriers with higher channel power gains will be granted the priority to be activated, given the number of subcarriers is fixed. We also analyze the proposed enhanced OFDM-SNM system in terms of outage and error performance. The average outage probability and block error rate (BLER) are derived and approximated in closed-form expressions, which are further verified by numerical results generated by Monte Carlo simulations. The high-reliability nature of the enhanced OFDM-SNM makes it a promising candidate for implementing in the Internet of Things (IoT) with stationary machine-type devices (MTDs), which are subject to slow fading and supported by proper power supply.Index Terms-Orthogonal frequency-division multiplexing with subcarrier number modulation (OFDM-SNM), subcarrier assignment, reliability enhancement, outage performance analysis, error performance analysis.

show abstract

“…Example Assume {N, K} = {4, 2}, i.e., four subcarriers in total and two of them are activated to form an SAP. Obviously, we have S = 4 2 = 6 SAPs, which can be expressed by ASVs ranked 9 One should note that it is possible and even common that for s = t, we have d s (σs) = d t (σt), which indicates that both leaves are equally preferable and can be ranked arbitrarily. When given a perfect binary tree, we will have d 1 (σ1) = d 2 (σ1) = · · · = d s (σs), and all leaves are equivalent.…”

Section: Enhanced Huffman Coding With Csimentioning

confidence: 99%

Enhanced Huffman Coded OFDM With Index Modulation

Dang

¹

,

Guo

²

,

Coon

³

et al. 2020

IEEE Trans. Wireless Commun.

View full text Add to dashboard Cite

In this paper, we propose an enhanced Huffman coded orthogonal frequency-division multiplexing with index modulation (EHC-OFDM-IM) scheme. The proposed scheme is capable of utilizing all legitimate subcarrier activation patterns (SAPs) and adapting the bijective mapping relation between SAPs and leaves on a given Huffman tree according to channel state information (CSI). As a result, a dynamic codebook update mechanism is obtained, which can provide more reliable transmissions.We take the average block error rate (BLER) as the performance evaluation metric and approximate it in closed form when the transmit power allocated to each subcarrier is independent of channel states.Also, we propose two CSI-based power allocation schemes with different requirements for computational complexity to further improve the error performance. Subsequently, we carry out numerical simulations to corroborate the error performance analysis and the proposed dynamic power allocation schemes. By studying the numerical results, we find that the depth of the Huffman tree has a significant impact on the error performance when the SAP-to-leaf mapping relation is optimized based on CSI. Meanwhile, through numerical results, we also discuss the trade-off between error performance and data transmission rate and investigate the impacts of imperfect CSI on the error performance of EHC-OFDM-IM.Orthogonal frequency-division multiplexing with index modulation (OFDM-IM), Huffman coding, dynamic codebook design, power allocation, channel state information (CSI).both provide good thoughts on how the Huffman tree architecture could be adapted to provide a higher capacity and transmission rate when utilizing all legitimate SAPs. In [25], Huffman coding was applied to OFDM-IM with the help of channel state information (CSI). However, the Huffman coded OFDM-IM scheme proposed in [25] did not fully exploit all legitimate SAPs, and thereby only shows limited improvements. The latest research results with respect to the optimization of the achievable rate of binary-tree coded OFDM-IM (a generic version of Huffman coded OFDM-IM) were presented in [26]. In this work, the achievable rate is optimized by dynamically varying the SAP probability distribution and transmit power allocated to active subcarriers. January 7, 2020 DRAFT

show abstract

“…Example Assume {N, K} = {4, 2}, i.e., four subcarriers in total and two of them are activated to form an SAP. Obviously, we have S = 4 2 = 6 SAPs, which can be expressed 9 One should note that it is possible and even common that for s = t, we have d s (σs) = d t (σt), which indicates that both leaves are equally preferable and can be ranked arbitrarily. When given a perfect binary tree, we will have d 1 (σ 1 ) = d 2 (σ 1 ) = · · · = d s (σs), and all leaves are equivalent.…”

Section: Enhanced Huffman Coding With Csimentioning

confidence: 99%

Enhanced Huffman Coded OFDM with \\Index Modulation

Dang¹,

Guo²,

Coon³

et al. 2020

Preprint

0

View full text Add to dashboard Cite

In this paper, we propose an enhanced Huffman coded orthogonal frequency-division multiplexing with index modulation (EHC-OFDM-IM) scheme. The proposed scheme is capable of utilizing all legitimate subcarrier activation patterns (SAPs) and adapting the bijective mapping relation between SAPs and leaves on a given Huffman tree according to channel state information (CSI). As a result, a dynamic codebook update mechanism is obtained, which can provide more reliable transmissions. We take the average block error rate (BLER) as the performance evaluation metric and approximate it in closed form when the transmit power allocated to each subcarrier is independent of channel states. Also, we propose two CSI-based power allocation schemes with different requirements for computational complexity to further improve the error performance. Subsequently, we carry out numerical simulations to corroborate the error performance analysis and the proposed dynamic power allocation schemes. By studying the numerical results, we find that the depth of the Huffman tree has a significant impact on the error performance when the SAP-to-leaf mapping relation is optimized based on CSI. Meanwhile, through numerical results, we also discuss the trade-off between error performance and data transmission rate and investigate the impacts of imperfect CSI on the error performance of EHC-OFDM-IM.Index Terms-Orthogonal frequency-division multiplexing with index modulation (OFDM-IM), Huffman coding, dynamic codebook design, power allocation, channel state information (CSI).

show abstract

Practical Implementation of Index Modulation-Based Waveforms

Cited by 31 publications

References 35 publications

Enhanced Orthogonal Frequency-Division Multiplexing With Subcarrier Number Modulation

Enhanced Orthogonal Frequency-Division Multiplexing With Subcarrier Number Modulation

Enhanced Huffman Coded OFDM With Index Modulation

Enhanced Huffman Coded OFDM with \\Index Modulation

Contact Info

Product

Resources

About