Hao Huan

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In this paper, we propose a generalized method of high-level three dimensional (3D) signal constellation mapping based on the most basic 3D structure: regular tetrahedron cells. First, we redefined the waveform design, the normalized frequency and phase modulation for the geometric construction of tetrahedron cells. Then, the new topology of tetrahedron(More)
Fractional Fourier transform (FRFT) has been widely used in orthogonal frequency division (OFDM) systems to combat the doubly dispersive channels. The sensitivity of the fractional order is a serious problem. In this paper, we derive the closed form of the variable order and its optimal value based on the mathematical expression in the FRFT-OFDM systems.(More)
Constellation mapping has provided a great convenience to measure the performance of digital signal modulation in Euclid space. However, traditional in-phase and quadrature (IQ) plane is difficult to express the frequency modulation scheme such as minimum shift keying (MSK) and the time domain modulation such as cyclic code shift keying (CCSK). How to(More)
Frequency spectrum resource is the most important and fundamental resource for various information systems such as communication systems, radar systems and so on. In order to overcome the conflicts between the scarcity and low usage efficiency, cognitive capability becomes more and more important for future information system designs. In this paper, we give(More)
Orthogonal Frequency Division Multiplexing (OFDM) using Fractional Fourier Transform (FrFT) normally known as Chirped OFDM is studied. The Constant Envelope of the Chirped OFDM is then obtained by phase modulation of the chirped OFDM and then its Peak to Average Power Ratio (PAPR) is analyzed. The study shows the Constant Envelope Chirped OFDM (CE-COFDM)(More)
In this paper, to solve the problem of co-channel interference caused by homo-type radars working in ship formation, an interference suppression method based on joint fractional Fourier domain and time domain is proposed. The interference with different modulated frequency rates from echo signal can be eliminated at fractional Fourier domain and the ones(More)
To reach a compromise between efficient dynamic performance and high tracking accuracy of carrier tracking loop in high-dynamic circumstance which results in large Doppler frequency and Doppler rate, a tracking loop structure aided by the estimation of Doppler rate is proposed in this paper. First, the instant self-correlation function is used for a process(More)
First, this paper analyzes the performance of the linear frequency modulation (LFM) interference in PN spread-spectrum communication systems. Second, in the light of suppressing the side-lobe of periodic LFM in fractional Fourier transform (FRFT) domain, a method combined transform-domain and time-domain is proposed, this method improves the processing gain(More)
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