EEOPA Algorithm for MIMO-OFDM with Energy-Efficiency and QOS Constraints

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International Journal of Innovative Research in Electronics and Communications (IJIREC) Volume 2, Issue 8, 2015, PP 16-22 ISSN 2349-4042 (Print) & ISSN 2349-4050 (Online) www.arcjournals.org EEOPA Algorithm for MIMO-OFDM with Energy-Efficiency and QOS Constraints 1 Sk.Nageena, 2 M.Ramana Reddy, 3 P.Prasanna Murali Krishna 1 (M.Tech), DECS, DR.SGIT, Markapur, India 2 Associate Professor, Department of ECE, DR.SGIT, Markapur, India. 3 H.O.D Department of ECE, DR.SGIT, Markapur, India Abstract: Wireless communications is, by any measure, the fastest growing segment of the communications industry. As such, it has captured the attention of the media and the imagination of the public. Cellular systems have experienced exponential growth over the last decade and there are currently around two billion users worldwide. Indeed, cellular phones have become a critical business tool and part of everyday life in most developed countries, and are rapidly supplanting antiquated wire line systems in many developing countries. In addition, wireless local area networks currently supplement or replace wired networks in many homes, businesses, and campuses. Many new applications, including wireless sensor networks, automated highways and factories, smart homes and appliances, and remote telemedicine, are emerging from research ideas to concrete systems. The mobile multimedia communication systems is rapid development the recent years. The main parameter is energy efficiency optimization and quality of service constraint for MIMO-OFDM communication. The various algorithm to be minimize the energy level for the transmitted signal. But it have some limitation. So we used proposed energy efficiency optimized power allocation (EEOPA).and to improve the energy efficiency for MIMO-OFDM mobile multimedia communication system. The EEOPA algorithm used to solve the problem of multi-channel optimize to multi target in single channel optimization. The method to calculate the channel characteristics using singular variable decomposition method (SVD). An energy-efficiency model is first proposed for MIMO-OFDM communication systems with statistical QoS constraints. By using (SVD) method, to view their channel characteristics. Furthermore, the optimization problem is in solved by grouping all sub channels. Therefore, a solution is derived for MIMO-OFDM systems. 1. INTRODUCTION The gap between current and emerging systems and the vision for future wireless applications indicates that much work remains to be done to make this vision a reality. Based on the pdf and the cdf of the maximum eigen value of double-correlated complex Wishart matrices, the exact expressions for the pdf of the output SNR were derived for MIMOMRC communication systems with Rayleigh fading channels. The closed-form expressions for the outage probability of MIMO-MRC communication systems with Rician fading channels were derived under the condition of the largest eigenvalue distribution of central complex Wishart matrices in the non-central case. Furthermore, the closed-form expressions for the outage probability of MIMO-MRC communication systems with and without co channel interference were derived by using cdfs of a Wishart matrix. Meanwhile, the pdf of the smallest eigenvalue of a Wishart matrix was applied to select antennas to improve the capacity f MIMO communication systems. However, most existing studies mainly worked on the joint pdf of eigenvalues of a Wishart matrix to measure the channel performance for MIMO communication systems. In this paper, sub channels gains derived from the marginal probability distribution of a Wishart matrix is investigated to implement energy-efficiency optimization in IMO-OFDM mobile multimedia communication systems. In conventional mobile multimedia communication systems, many studies have been carried out. In terms of the corresponding QoS demand of different throughput levels in MIMO communication systems, an effective antenna assignment scheme and an access control scheme were proposed in. A downlink QoS evaluation scheme was proposed from the viewpoint of mobile users in orthogonal frequency-division multiple-access (OFDMA) wireless cellular networks. ARC Page 16

Sk.Nageena et al. 2. LITERATURE SURVEY 2.1. Accurate and Efficient Simulation of Multiple Uncorrelated Rayleigh Fading Waveforms (2007) Author Name: C.-X. Wang, M. Patzold, and D. Yuan The advantage we may take from this property is that various local minima lead to various disjoint sets of discrete frequencies. Its derivatives are of deterministic nature, which has the advantage of simulation efficiency, they still retain some undesirable properties. An obvious disadvantage with the above selection is that very large values have to be chosen. This greatly the complexity of our channel simulator, when uncorrelated Rayleigh processes are simulated. 2.2. Energy Efficiency Evaluation of Cellular Networks Based on Spatial Distributions of Traffic Load and Power Consumption (2013) Author name: L. Xiang, X. Ge, C-X. Wang, F. Li, and F. Reichert Aiming to carry the largest amount of traffic load while satisfying the required quality of service (QoS) using limited radio resources. The required total transmission power exhibits a significant degree of bustiness, indicating higher demand for large transmission power to support self-similar traffic load. A convex optimization problem and a set of link parameters were derived to maximize energy efficiency under given QoS constraints. This problem, energy is also an important type of radio resource, except that the objective now becomes to minimize energy Consumption per traffic bit, for energy efficiency. 2.3. Spectral-Energy Efficiency Tradeoff in Relay-Aided Cellular Networks (2013), Author Name: I. Ku, C. Wang, and J. S. Thompson The using Hadamard s inequality and the fact that the diagonal elements of and are unity, it can be easily shown that performance in the high SNR regime. This proved that MIMO-MRC achieves the maximum available spatial diversity order in doublecorrelated channels. In uncorrelated Rayleigh fading was considered, and the output SNR statistical properties were derived based on maximum eigen value statistics of complex central Wishart matrices. In uncorrelated Rician channels were characterized using maximum eigenvalue properties of complex non central Wishart matrices 2.4. Performance Analysis of MIMO-MRC in Double-Correlated Rayleigh Environments (2007) Author name: M. R. McKay, A. J. Grant, and I. B. Collings. The using Hadamard s inequality and the fact that the diagonal elements of and are unity, it can be easily shown that performance in the high SNR regime. we proved that MIMO-MRC achieves the maximum available spatial diversity order in doublecorrelated channels. In uncorrelated Rayleigh fading was considered, and the output SNR statistical properties were derived based on maximum eigen value statistics of complex central Wishart matrices. In uncorrelated Rician channels were characterized using maximum eigenvalue properties of complex non central Wishart matrices. International Journal of Innovative Research in Electronics and Communications (IJIREC) Page 17

EEOPA Algorithm for MIMO-OFDM with Energy-Efficiency and QOS Constraints 3. EXISTING SYSTEM The QoS statistical exponent is fixed as the impact of the average power constraint on the energy efficiency and the effective capacity of MIMO-OFDM mobile multimedia communication systems. The energy efficiency decreases with the increase in the average power constraint, and the effective capacity increases with the increase in the average power constraint. An average transmission power constraint P is configured for each sub channel; thus, the transmission power allocation threshold of each sub channel should satisfy the following constraint. When the QoS statistical exponent is fixed the impact of the average power constraint on the energy efficiency and the effective capacity of MIMO-OFDM mobile multimedia communication systems is investigated in the energy efficiency decreases with the increase in the average power constraint, and the effective capacity increases with the increase in the average power constraint. This result implies that there is an optimization tradeoff between the energy efficiency and effective capacity in MIMO- OFDM mobile multimedia communication systems: As the transmission power increases, which leads to larger effective capacity, the energy consumption of the system also rises; therefore, the larger power input results in the decline of energy efficiency. The multichannel joint optimization problem in conventional MIMOOFDM communication systems is transformed into a multi target single-channel optimization problem by grouping all sub channels. To improve energy efficiency with a QoS constraint is an indispensable problem in MIMOOFDM mobile multimedia communication systems. There has been few research work addressing the problem of optimizing the energy efficiency under different QoS constraints in MIMO-OFDM mobile multimedia communication systems. The sub channels in different groups, which simplifies the multichannel optimization problem to a multi target single channel optimization problem. 4. PROPOSED SYSTEM Based on the Wishart matrix theory numerous channel models have been proposed in the literature for MIMO communication systems. In conventional mobile multimedia communication systems, many studies have been carried out. In terms of the corresponding QoS demand of different throughput levels in MIMO communication systems, an effective antenna assignment scheme and an access control scheme were proposed in. A downlink QoS evaluation scheme was proposed from the viewpoint of mobile users in orthogonal frequency-division multiple-access (OFDMA) wireless cellular networks. On the effective capacity of the block fading channel model, a QoS driven power and rate adaptation scheme over wireless links was proposed for mobile wireless networks. Furthermore, by integrating information theory with the effective capacity, some QoS-driven power and rate adaptation schemes were proposed for diversity and multiplexing systems. Simulation results showed that multichannel communication systems can achieve both high throughput and stringent QoS at the same time. Aiming at optimizing the energy consumption, the key tradeoffs between energy efficiency and link-level QoS metrics were analyzed in different wireless communication scenarios. On the effective capacity of the block fading channel model, a QoS driven power and rate adaptation scheme over wireless links was proposed for mobile wireless networks. Furthermore, by integrating information theory with the effective capacity, some QoS-driven power and rate adaptation schemes were proposed for diversity and multiplexing systems. The advantages on improving the energy efficiency and effective capacity of MIMO-OFDM mobile multimedia communication systems with QoS constraints. It is widely recognized that, in addition to the quality of service (QoS), energy efficiency is also a key parameter in designing and evaluating mobile multimedia communication systems. The performance of high spectral efficiency MIMO communication systems with multiple phase-shift keying signals in a flat Rayleigh fading environment was investigated in terms of symbol error probabilities. Simulation results showed that multichannel communication systems can achieve both high throughput and stringent QoS at the same time. This happens because the larger values of θ International Journal of Innovative Research in Electronics and Communications (IJIREC) Page 18

Sk.Nageena et al. correspond to the higher QoS requirements, which result in a smaller number of sub channels being selected to satisfy the higher QoS requirements. Flow Diagram 5. ALGORITHM DESIGN The core idea of energy-efficiency optimized power-allocation algorithm (EEOPA) with statistical QoS constraints for MIMO-OFDM mobile multimedia communication systems is described as follows. First, the SVD method is applied for the channel matrix Hk, k = 1, 2,..., N, at each orthogonal subcarrier to obtain M N parallel space frequency sub-channels. Second, sub-channels at each subcarrier are pushed into a sub-channel gain set, where sub-channels are sorted by the subchannel gain in descending order, and then, the sub-channels with the same order position in the subchannel gain set are selected into the same group. Since the sub-channels within the same group have the identical pdf, the transmission power-allocation threshold for the sub-channels within the same group is identical. Therefore, the optimized transmission power allocation for the grouped subchannels is implemented to improve the energy efficiency of MIMO-OFDM mobile multimedia Algorithm 1 EEOPA. Input: M t, M r, N,H k,, B, T f, θ; Initialization: Decompose the MIMO-OFDM channel ma-trixh k (k = 1, 2,..., N ) into M N space frequency sub-channels through the SVD method. Begin: 1) Sort sub-channel gains of each subcarrier in decreasing order as follows: λ 1, k λ 2,k λ M, k (k = 1, 2,..., N ). (1) 2) Assign λ n, 1, λ n, 2,...,λ n, N from all N subcarriers into the nth-group sub-channel set as follows: Group_n = {λ n, 1, λ n, 2,,λ n, N }, n = 1, 2,, M. (2) 3) for n = 1 : M do Calculate the optimized transmission power-allocation threshold Λn for Group_n according to the average power constraint as follows: International Journal of Innovative Research in Electronics and Communications (IJIREC) Page 19

EEOPA Algorithm for MIMO-OFDM with Energy-Efficiency and QOS Constraints (3) Execute the optimized transmission power-allocation policy for Group_n as follows: (4) Calculate the optimized effective capacity for Group_n: as follows: end for 4) Calculate the optimized energy efficiency of the MIMO-OFDM mobile multimedia communication system as follows: (5) end Begin Output : (6) 6. SIMULATION RESULTS Fig. GUI Screen for the input audio signal International Journal of Innovative Research in Electronics and Communications (IJIREC) Page 20

Sk.Nageena et al. Fig. signal to noise ratio to QOS 7. CONCLUSION Fig. comparison effective capacity to power In this paper, an energy-efficiency model is proposed for MIMO-OFDM mobile multimedia communication systems with statistical QoS constraints. An energy-efficiency optimization scheme is presented based on the sub-channel grouping method, in which the complex multichannel joint optimiza-tion problem is simplified into a multitarget single-channel optimization problem. A closedform solution of the energy-efficiency optimization is derived for MIMO-OFDM mobile multimedia communication systems. Moreover, a novel algorithm, i.e., EEOPA, is designed to improve the energy efficiency of MIMO-OFDM mobile multimedia communication systems. Compared with the traditional APA algorithm, simulation results demonstrate that our proposed algorithm has advantages on improving the energy efficiency and effective capacity of MIMO-OFDM mobile multimedia communication systems with QoS constraints REFERENCES [1] I. Humar, X. Ge, X. Lin, M. Jo, and M. Chen, Rethinking energy efficiency models of cellular networks with embodied energy, IEEE Netw., vol. 25, no. 2, pp. 40 49, Mar./Apr. 2011. [2] C.-X.Wang, F. Haider, X. Gao, X.-H. You, Y. Yang, D. Yuan, H. Aggoune, H. Haas, S. Fletcher, and E. Hepsaydir, Cellular architecture and key technologies for 5G wireless communication networks, IEEE Commun. Mag., vol. 52, no. 2, pp. 122 130, Feb. 2014. [3] S. Raghavendra and B. Daneshrad, Performance analysis of energy efficient power allocation for MIMO-MRC systems, IEEE Trans. Commun., vol. 60, no. 8, pp. 2048 2053, Aug. 2012. International Journal of Innovative Research in Electronics and Communications (IJIREC) Page 21

EEOPA Algorithm for MIMO-OFDM with Energy-Efficiency and QOS Constraints [4] J. Liu, Y. T. Hou, Y. Shi, and D. S. Hanif, Cross-layer optimization for MIMO-based wireless ad hoc networks: Routing, power allocation, and bandwidth allocation, IEEE J. Sel. Areas Commun., vol. 26, no. 6, pp. 913 926, Aug. 2008. [5] J. Ding, D. Deng, T. Wu, and H. Chen, Quality-aware bandwidth allocation for scalable ondemand streaming in wireless networks, IEEE J. Sel. Areas Commun., vol. 28, no. 3, pp. 366 376, Apr. 2010. [6] X. Su, S. Chan, and J. H. Manton, Bandwidth allocation in wireless ad hoc networks: Challenges and prospects, IEEE Commun. Mag., vol. 48, no. 1, pp. 80 85, Jan. 2010. [7] D. Helonde, V. Wadhai, V. S. Deshpande, and H. S. Ohal, Performanceanalysis of hybrid channel allocation scheme for mobile cellular network, in Proc. ICRTIT, Jun. 2011, pp. 245 250. [8] C.-X. Wang, M. Patzold, and D. Yuan, Accurate and efficient simulation of multiple uncorrelated Rayleigh fading waveforms, IEEE Trans. Wireless Commun., vol. 6, no. 3, pp. 833 839, Mar. 2007. [9] L. Xiang, X. Ge, C-X. Wang, F. Li, and F. Reichert, Energy efficiency evaluation of cellular networks based on spatial distributions of traffic load and power consumption, IEEE Trans. Wireless Commun., vol. 12, no. 3,pp. 961 973, Mar. 2013. [10] C. Chen, W. Stark, and S. Chen, Energy-bandwidth efficiency tradeoff in MIMO multi-hop wireless networks, IEEE J. Sel. Areas Commun., vol. 29, no. 8, pp. 1537 1546, Sep. 2011. [11] F. Heliot, M. A. Imran, and R. Tafazolli, On the energy efficiency spectral efficiency trade-off over the MIMO Rayleigh fading channel, IEEE Trans. Commun., vol. 60, no. 5, pp. 1345 1356, May 2012. [12] I. Ku, C. Wang, and J. S. Thompson, Spectral-energy efficiency tradeoff in relay-aided cellular networks, IEEE Trans. Wireless Commun., vol. 12, no. 10, pp. 4970 4982, Oct. 2013. [13] X. Hong, Y. Jie, C. Wang, J. Shi, and X. Ge, Energy-spectral efficiency trade-off in virtual MIMO cellular systems, IEEE J. Sel. Areas Commun., vol. 31, no. 10, pp. 2128 2140, Oct. 2013. [14] I. Ku, C. Wang, and J. S. Thompson, Spectral, energy and economic efficiency of relay-aided cellular networks, IET Commun., vol. 7, no. 14, pp. 1476 1486, Sep. 2013. [15] R. A. Fisher, Frequency distribution of the values of the correlation coefficient in samples from an indefinitely large population, Biometrika, vol. 10, no. 4, pp. 507 521, May 1915. [16] J.Wishart, The generalized product moment distribution in samples from a normal multivariate population, Biometrika, vol. 20A, no. 1/2, pp. 32 52, Jul. 1928. [17] J. Wishart, Proofs of the distribute on law of the second order moment statistics, Biometrika, vol. 35, no. 1/2, pp. 55 57, May 1948. International Journal of Innovative Research in Electronics and Communications (IJIREC) Page 22