In this article, we concerned with the performance of high rate space time block code (STBC) scheme for Frequency selective fading Environment. Due to large channel delay spread in Frequency selective channel inter symbol interference (ISI) occurred. In high rate STBC, ISI occurs due to loss of „quasi – static‟ assumption and Classical Zero forcing (ZF) receiver produces error floor in Bit erro...

Blind fractionally spaced equalizers reduce intersymbol interference using second-order statistics without the need for training sequences. Methods for finding FIR zero-forcing blind equalizers directly from the observations are described, and adaptive versions are developed. In contrast, most current methods require channel estimation as a first step to estimating the equalizer. The direct met...

Zero forcing is a game played on a graph that starts with a coloring of the vertices as white and black and at each step any vertex colored black with a unique neighbor colored white “forces” the color of the white vertex to become black. In this note we look at what happens when we balance the size of the initial set of vertices colored black and the number of steps, called speed of propagaion...

In this paper, we investigate the Zero-Forcing equalizer based on Fast One Sided Jacobi (ZF-FOSJ) algorithm for the Multiple Input Multiple Output Power Line Communication (MIMO PLC) systems. The proposed algorithm determines the pseudo-inverse of estimated channel matrix using only real matrix and operations free from trigonometric functions. The hardware implementation complexity is reduced c...

We propose a modulus based zero-forcing (MZF) detection for multi-input multi-output (MIMO) channels. Traditionally, a ZF detector nulls out all interferences from other layers when detecting a current layer, which can yield suboptimal detection-performance due to the noise-enhancement issue. In many communication systems, finite alphabets such as M quadrature-amplitude-modulation (QAM) are wid...

Zero forcing can be described as a graph process that uses color change rule in which vertices white to blue. The throttling number of minimizes the sum initially colored blue and time steps required entire graph. Positive semidefinite (PSD) zero is commonly studied variant standard alters rule. This paper introduces method for extending using PSD process. Using this extension method, graphs wi...

Abstract— In this article we show that a Code Division Multiple Access (CDMA) system employing long codes can be interpreted as a Multiple Input Multiple Output system where the transmit filters are time-varying. We derive conditions for existence of zero-forcing equalizers and verify through simulations that these conditions are useful guidelines for the design of appropriate solution in the p...

あらまし 厳しい周波数選択性環境下では大きな符号間干渉(ISI)が発生するため,シングルキャリア(SC)伝送の 平均ビット誤り率(BER)特性は著しく劣化してしまう.最近,周波数選択性フェージングを克服する技術として, 最小平均二乗誤差規範に基づく周波数領域等化(MMSE-FDE)が注目を浴びている.MMSE-FDE では,ISI を抑圧し つつ周波数ダイバーシチ利得を獲得できるため,SC 伝送の BER 特性を大幅に改善できる.しかし ISI が残留する ため,BER の理論的な下界を達成することはできない.筆者らはこれまで,送信機で Tomlinson-Harashima precoding (THP)を用いることで受信機での FDE 後の残留 ISI を抑圧し,特に 16QAM や 64QAM などの高レベル多値変調を用 いたときの BER 特性を改善できることを示してきた.本...

The effects of cooperating base stations in the downlink of an OFDM-based cellular network with frequency reuse factor one are studied. In this so-called network MIMO scenario the signals of several users are jointly processed before transmission in order to handle the unavoidable multi-user interference. We apply and study pre-processing techniques well-known from conventional MIMO scenarios i...

The performance of linear interference suppression in a DS-CDMA (Direct-Sequence Code Division Multiple Access) system using random codes varies over the user population due to the random set of interfering sequences. As a result , the capacity of such systems depends on the distribution of the interfering signature sequences and consequently the distribution of the signal-to-interference ratio...