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Kee-Hoon Kim - IEEE Xplore Author Profile

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Orthogonal frequency division multiplexing with index modulation (OFDM-IM) is a novel scheme where the information bits are conveyed through the subcarrier activation pattern (SAP) and the symbols on the active subcarriers. Specifically, the subcarriers are partitioned into many subblocks and the subcarriers in each subblock can have two states, active or idle. Unfortunately, OFDM-IM inherits the ...Show More
Orthogonal frequency division multiplexing with index modulation (OFDM-IM) is a novel multicarrier scheme, which uses {k} out of {n} subcarriers as active subcarriers to transmit data. For detecting the subcarrier activation pattern (SAP) at the receiver, maximum likelihood (ML) detection cannot be used because of its high computational complexity. Instead, the detector selecting the most ...Show More
In orthogonal frequency division multiplexing with index modulation (OFDM-IM), the active subcarriers can convey information bits by modulated symbols as well as their indices. OFDM-IM has attracted a great deal of attention from researchers by virtue of high energy efficiency. Unfortunately, OFDM-IM has inherited large peak-to-average power ratio (PAPR) of the classical OFDM signal, but there are...Show More
Dual mode orthogonal frequency division multiplexing with index modulation (DM-OFDM-IM) is recently proposed, where the subcarriers within each subblock are divided into two groups, which are modulated by two distinguishable signal constellations. That is, the DM-OFDM-IM activates all subcarriers to convey data and eliminate the limits of spectrum efficiency in OFDM with index modulation (OFDM-IM)...Show More
Orthogonal frequency division multiplexing with index modulation (OFDM-IM) is a novel multicarrier scheme, which uses the indices of the active subcarriers to transmit data. The OFDM-IM also inherits the high peak-to-average power ratio (PAPR) problem, which induces in-band distortion and out-of-band radiation when OFDM-IM signal passes through high-power amplifier (HPA). In this letter, dither si...Show More
In this paper, two partial transmit sequence (PTS) schemes without side information (SI) are proposed for reducing peak-to-average power ratio of orthogonal frequency division multiplexing signals. The proposed schemes do not transmit SI identifying a rotating vector because identifiable phase offset is applied to the elements of each rotating vector. To extract SI from the received signal and rec...Show More
Partial transmit sequence (PTS) is a probabilistic peak-to-average power ratio (PAPR) reduction scheme for orthogonal frequency division multiplexing (OFDM) signals, but it requires an exhaustive search for the one with the minimum PAPR over all alternative OFDM signal vectors. In order to reduce such computational complexity, it was proposed that the PAPR value of each alternative OFDM signal vec...Show More
The performance of an orthogonal frequency division multiplexing system is degraded in the presence of narrowband interference (NBI). This degradation arises from spectral leakage of the interference power during demodulation, corrupting many subcarriers. There have been many attempts to mitigate the NBI, but most schemes need some prior information about the NBI or resources in frequency or time ...Show More
Orthogonal frequency division multiplexing (OFDM) signals have high peak-to-average power ratio (PAPR), which causes distortion when OFDM signal passes through a nonlinear high power amplifier. A partial transmit sequence (PTS) scheme is one of the typical PAPR reduction methods. A cyclic shifted sequences (CSSs) scheme is evolved from the PTS scheme to improve the PAPR reduction performance, wher...Show More
As a metric for amplitude fluctuation of orthogonal frequency division multiplexing (OFDM) signal, cubic metric (CM) has received an increasing attention because it is more closely related to the distortion induced by nonlinear devices than the well-known peak-to-average power ratio (PAPR). In this letter, the properties of CM of OFDM signal is investigated. First, asymptotic distribution of CM is...Show More
Selected mapping (SLM) is a well-known peak-to-average power ratio (PAPR) reduction technique for orthogonal frequency division multiplexing (OFDM) systems. Recently, a low-complexity SLM scheme, called Class-III SLM scheme, was proposed, which performs only one inverse fast Fourier transform (IFFT) to generate alternative OFDM signal sequences. By randomly selecting the cyclic shift and rotation ...Show More
In this paper, a clipping noise cancelation scheme using compressed sensing (CS) technique is proposed for orthogonal frequency division multiplexing systems. The proposed scheme does not need reserved tones or pilot tones, which is different from the previous works using CS technique. Instead, observations of the clipping noise in data tones are exploited, which leads to no loss of data rate. Als...Show More
In this paper, a new SLM scheme for peak to average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDM) systems is proposed. This scheme is special case of selected mapping (SLM) scheme. The proposed SLM scheme generates alternative OFDM signal sequences by exploiting the intermediate OFDM signal sequence in inverse fast Fourier transform (IFFT). By using this techniq...Show More