Informatics Publishing Limited

L. C. Siddanna Gowd ¹, A. Natarajan ¹, M. Manikandan ¹, R. Pavendiran ¹

Affiliations
1 ECE Department, AMS Engineering College, T.N, IN

Abstract

The use of multiple antennas at both the transmitter and receiver has been proposed as one of the best way to provide both an increase in reliability and also in information transmission rate. In this paper, the importance of the quantity and quality of the channel state information available at the communication ends is explored so as to achieve high data rates. The different architectures for various degrees of quality and quantity of CSI are studied in this work. The presented architectures are shown to be robust to the uncertainties of CSI. The main focus of this work is to dynamically provide resource allocation so as to achieve better QoS and improve system capacity.

Keywords

Multi-Input Multi-Output (MIMO), Orthogonal Frequency Division Multiplexing (OFDM), Channel Side Information (CSI).

Full Text

     

B. Ramamurthy ¹, L. C. Siddanna Gowd ²

Affiliations
1 Electronics and Instrumentation Department, S.K.University, Anantapur, IN
2 S. K. University, Anantapur, IN

Abstract

In conventional wireless communication system the problem of estimating the parameters such as coherence time, coherence band width etc. is still not accurate. This problem is mainly due to the fact that the mobile receiver can be in motion and also received signals can arrive along multiple reflected paths. In this work, the channel modeling, optimal location reflectors and scatterers with respect to the location of transmitter and receiver and the optimal valve of angular range with the direction of motion of the mobile receiver are to be explored. The effect of the multipath fading both over time and frequency is also to be considered. The algorithms and schemes proposed in this paper shall benefit in the (i) optimal location of scatterers around a receiver moving at a variable speed (ii) realistic modeling of MIMO fading channels overcoming the conventional assumption that fading coefficients between different transmit and receive antennas are independent random variables.

Keywords

Multipath Fading, Mobility Models, MIMO Fading Channel, Channel Uncertainty.

Full Text

     

V. Vidya Devi ¹, L. C. Siddanna Gowd ², A. Natarajan ³, Guru Kumar Lokku ⁴

Affiliations
1 Department of ECE, A.M.S. Engineering College, T.N., IN
2 ECE Department, A.M.S Engineering College, T.N., IN
3 A.M.S Engineering College, T.N., IN
4 VLSI Design, Department of ECE, A.M.S Engineering College, T.N., IN

Abstract

A probabilistic estimation bias (PEB) circuit for a fixed-width two’s complement Booth multiplier is proposed for Low Power and High accuracy. The proposed PEB circuit is derived from theoretical computation, instead of exhaustive simulations and heuristic compensation strategies that tend to introduce curve-fitting errors (interpolation) and exponential-grown simulation time. Consequently, the proposed PEB circuit provides a smaller area and a lower truncation error compared with existing works such as posttruncation and pre-truncation methodologies in Booth Multiplication. Implemented in an 8×8 2-D discrete cosine transform (DCT) core, the DCT core using the proposed PEB Booth multiplier improves the peak signal-to-noise ratio by 17 dB with only a 2% area penalty compared with the direct-truncated method. This PEB circuit also provides extensive applications in digital designs. PEB circuit are more easier to design and can achieve good simulation time in doing computations in higher order bits.

Keywords

Discrete Cosine Transform (DCT), Estimation Theory, Fixed-Width Booth Multiplier, Probabilistic Analysis.

Full Text

     

B. R. Tapas Bapu ¹, L. C. Siddanna Gowd ²

Affiliations
1 Department of Electronics and Communication Engineering, St.Peters University, Chennai - 600054, Tamil Nadu, IN
2 AMS College, Namakkal - 637013, Tamil Nadu, IN

Abstract

Objectives: The networks using wireless sensor are becoming the preferred considerations for the critical mission applications. These applications normally remain unattended for years and have to perform reliably for lifetime. However the performance of these systems is subject to significant degradation over time because of realities in sensing and failure, communication in real world, node faults and clock drift. Hence it becomes essential to continuously monitor the natural deteriorations and have provisions for self-healing as necessary. Methods/Statistical Analysis: The self-healing, error correction and node authentication are proposed by this paper. The network having wireless sensors has nodes that are dynamically forming into clusters. Every cluster group will be having a cluster head for verifying the whole node. Findings: The cluster head would authenticate any incoming node of this network through generating and verifying signatures on any message using the Elliptic Curve Cryptography based Digital Signature Algorithm (ECCDSA). The registration of new node and authentication of the node constitutes the successful process of the authentication and cluster head would store the information about authentication in server. Application/ Improvement: The presence of malicious nodes if any will be identified using the distribution process of the self-healing key and the malicious nodes will be thrown out of the cluster by cluster head so as to guarantee the network as secured. After identifying and removing this malicious node in the cluster, the properties of that malicious node would be stored in the server for future reference. During error correction process, any node having the property same as this malicious one will be identified and informed to the cluster head by any neighbor node. Then using the technique of Forward Error Correction (FEC), the Cluster Head (CH) will block that node having the same malicious property after comparing with the one stored in the server.

Keywords

Cluster Head, Greedy Algorithm, MAODV, PEACH, Self- Healing Routing.

Full Text