Ranjeeth M
@vaagdevi.edu.in
Assistant Professor
Vaagdevi College of Engineering Warangal
Scopus Publications
Scopus Publications
R. Kiran Chand, Bittu Kumar, M.Ranjeeth, Kiran Dasari, Pulkit Singh, and K. Sai Pavan
IEEE
Panoramic image stitching is a popular technique for combining numerous photographs to generate wide-angle views and high-resolution images, Image stitching entails matching the pictures, adjusting for camera location and orientation discrepancies, and mixing the images to form a smooth composite image. In this paper, we offer an implementation of panoramic image stitching using Image processing techniques in python. The suggested technique employs feature-based image alignment, which aligns pictures by utilizing feature points in the images. The detection of spatial differences between the pixels of the image is a key to detect feature points, which is resistant to changes in scale, rotation, and affine distortion. After aligning the photos, we generate a smooth composite image. The suggested approach is tested on a real-world picture collection, and the findings demonstrate that it can generate high-quality panoramic photos with good alignment and smooth blending. The suggested approach is simple and straightforward to apply, and it has applications in virtual reality, surveillance and security systems, and film and video creation.
D Srikar, Anveshkumar Nella, Ranjith Mamidi, Ashok Babu, Sudipta Das, Sunil Lavadiya, Abeer D. Algarni, and Walid El-Shafai
MDPI AG
In this article, a cognitive radio (CR) integrated antenna system, which has 1 sensing and 24 communication antennas, is proposed for better spectrum utilization efficiency. In the 24 communication antennas, 3 different operating band antennas are realized with an 8-element MIMO configuration. The sensing antenna linked to port 1 is able to sense the spectrum that ranges from 2 to 12 GHz, whereas the communication 8-element MIMO antennas linked with ports 2 to 9, ports 10 to 17 and ports 18 to 25 perform operations in the 2.17–4.74 GHz, 4.57–8.62 GHz and 8.62–12 GHz bands, respectively. Mutual coupling is found to be less than −12 dB between the antenna elements. Peak gain and radiation efficiency of the sensing antenna are better than 2.25 dBi and 82%, respectively, whereas the peak gains and radiation efficiencies of all communication antennas are more than 2.5 dBi and 90%, respectively. Moreover, diversity characteristics of the MIMO antenna are assessed by parameters such as DG, ECC and CCL. It is found that ECC and CCL are less than 0.42 and 0.46 bits/s/Hz, respectively, and also DG is more than 9.1 dB.
Srinivas Nallagonda, Oruganti Lakshmi Prathyusha, and M. Ranjeeth
IEEE
This current research, the performance of a general-ized $a$- µ fading for the energy detection based spectrum sensing (ED-SS) in existence of channel errors is studied. Accurately, cognitive radio (CR) senses a primary user (PU), receives the sensing information, then it takes a binary-decision about active or inactive status of PU with the help of energy detector. So as to achieve, first the expression for novel-analytic is derived for probability of detection which is concerned to noise also for $\\alpha-\\mu$ fading. Next, based on the derived expression the frame works which are analytic to evaluate the total error rate (TER) and the complementary receiver operating charac-teristics (CROC) performances of a CR for all the parameters of channel and network are elaborated. Additionally, the ED-SS performance for various parameters namely as probability of channel error, detection threshold and signal-to- noise ratio (SNR) is investigated. Optimal detection threshold for several channel and network parameters are also determined. Finally, the numerical analysis of ED-SS without channel errors is also presented for comparison purpose. Analytical results are achieved using MATLAB numerical simulation.
M. Shashidhar, M. Ranjeeth, B. Santosh, and V. Manohar
IEEE
This paper discusses the key wireless networking infrastructure practices that maximize both the range and capability of a wireless communication device. To satisfy these demands, new methods have to be created and placed in place. The advanced LTE was the 4G counterpart to the 3G Universal Mobile Telecommunications System (UMTS) system and was built to provide a further evolution of the available mobile telecommunications system. It delivers much faster download rates and dramatically it provides better performance as well as lower running costs. Initial implementations offered little improvement over the generic HSPA+ 3GPP in Release 7, but soon it was recognized that LTE's full capacity provided a full 4G performance level. The goal of our work is to examine the analysis of advanced LTE and HSPA+ under various frequency bands in order to meet the requirements of international mobile telecommunications advanced system (IMT- Advanced).
Srinivas Nallagonda, Ranjeeth Mamidi, and Abhijit Bhowmick
Wiley
Cognitive radio (CR) is an advanced technique used for the utilization of radio spectrum. A CR node uses the radio spectrum of a licensed user (called as primary user, PU) deviously. In this work, a cooperative sensing network (CSN) with improved energy detection (IED)‐based CR nodes is proposed. Each CR node consists of multiple antennas and perform themselves selection diversity (SC) technique. Each CR node senses a PU through erroneous sensing channel and reports its sensing data (1‐bit binary‐decision) to the fusion center (FC) through erroneous reporting channels. At FC, existence of PU (presence or absence) is identified using k‐out‐of‐N fusion rule. The novel expressions for detection probability over noise plus Nakagami‐q/n fading channels are derived and the mathematical frameworks for analysis of throughput and energy‐efficiency of the proposed network are developed. The simulation testbed is also developed and presented in this work to validate the analytically obtained performance characteristics. For several network parameters values, the investigation on comparison between IED and traditional energy detection method for various decision fusion rules is studied. Further, performance characteristics are analytically illustrated for throughput and energy‐efficiency over noise plus Nakagami‐q/n fading channels. The impact of diversity technique and effect of fading severity parameters on the throughput and energy‐efficiency are also investigated. The effect of channel error on total error performance for both proposed and conventional networks is shown. Finally, optimal fusion rule and optimal network parameters values correspond to maximum throughput and maximum energy‐efficiency are also identified.
Santosh K Boddupelli, B.Naveen Kumar, M. Ranjeeth, and Srinivas Nallagonda
IEEE
The proposed cooperative spectrum sensing network gives potential attributes to improve the detection performance. This research paper mainly focuses on the identification of unknown signals in Weibull fading environment using an improved energy detector (IED). The proposed network consists of multiple cognitive radio (CR) nodes, at each CR node number of antennas are used and selection combining (SC) is used to select the maximum value of detection probability. Further, the activity of primary user (PU) is identified using fusion rules at fusion center (FC). Initially, closed-form of missed detection and false alarm probabilities are proficiently derived. Later on, energy efficiency and an average channel throughput analysis are evaluated using $k= 1 +n$ and $k=N- n$ rules at FC.
M. Ranjeeth, V. Manohar, A. Sai Supriya, M. Vinay, and M. Bhargav
IEEE
One of the most promising technologies for future mobile networks is non orthogonal multiple access (NOMA). Hence, most of academic and industry people are working on this technique to evaluate the error performance and to know the capacity of NOMA scheme. In this paper, we have considered a NOMA system in which two users are separated with an equal distance from base station (BS). The bit error rate (BER) performance is evaluated over non-fading (AWGN) and fading (Rayleigh, Rician, Nakagami-m and Weibull) environments for an arbitrary NOMA user. For two users, different power levels are provided. During the transmission of data, BPSK modulation scheme is considered and superposition coding is used at base station (BS). Successive interference cancellation (SIC) decoding mechanism in applied at receiver. Finally, with the help of MATLAB simulations, BER performances are evaluated. The comparative BER analysis for different environments is also provided.
Srinivas Nallagonda, Kiran Kumar Godugu, and M. Ranjeeth
IEEE
In this work, energy efficiency of a cognitive radio network (CRN) with improved energy detection (IED) based CR nodes in Nakagami-q fading is proposed. All the CR nodes contain the number of antennas and use selection diversity (SC) technique. Each CR node senses a PU using erroneous sensing links and reports its sensing information (one-bit decision) to fusion center (FC) with the help of erroneous reporting links. The decision about PU status (final) is taken by performing k-out-of-N fusion rule. The mathematical framework for energy efficiency analysis for the proposed network is developed. The simulation results is also discussed to validate the performance characteristics obtained analytically. For several network parameters values, the comparison through various various metrics between IED and traditional energy detection method under different fusion rules is studied. The impact of diversity technique and effect of fading severity parameters on the energy efficiency is also investigated. The effect of channel error on energy efficiency performance for both proposed and conventional networks is presented. Finally, optimal network parameters values for achieving maximum energy efficiency are also highlighted.
M. Ranjeeth, S. Anuradha, and Srinivas Nallagonda
Wiley
The proposed cooperative spectrum sensing (CSS) network is equipped with multiple antennas and an improved energy detector (IED) scheme at each cognitive radio (CR). Each CR in the network receives the information about the primary user (PU) in the form of binary decisions at multiple antennas. Diversity technique called selection combining (SC) scheme is used at multiple antennas to select the maximum value of sensing information present at multiple antennas. Finally, sensing information will be passed to the fusion center (FC) through reporting channel, and the final decision about PU is made at FC using fusion rules. Initially, we have derived the novel missed detection probability expressions for AWGN channel, Rayleigh, and Rician fading environments. Later, the closed form of optimized expressions for proposed CSS network parameters are derived to achieve an optimal performance. The closed form of optimized expressions such as number of CR users (Nopt), normalize threshold value (λn,opt), and an arbitrary power of the received signal (popt) are derived under various fading environments. The performance is evaluated using complementary receiver operating characteristics (CROC) and total error rate curves. The MATLAB‐based simulations are evaluated with the strong support of theoretical expressions. Finally, various simulation parameters such as sensing channel SNR, the error rate in reporting channel, threshold value, and number of antennas at each CR are considered in the simulation to show the effect on the performance of proposed CSS network.
M. Ranjeeth and S. Anuradha
IEEE
In this paper, we have analyzed the performance of an average channel throughput analysis using an improved energy detector (IED) under non-fading environment (AWGN channel) in cooperative spectrum sensing (CSS) network. The performance analysis is evaluated using different fusion rules (k=1+n and k=M-n) at fusion center (FC). The error rate is considered in reporting channel (R-channel) to show the effect of an error on the average channel throughput. Our simulation results gives the analysis of an average channel throughput for various values of detection thresholds, number of secondary users (M), and error rates in R-channel using different fusion rules at FC. The average channel throughput performance comparison between error free and error present in R-channel is provided using the MATLAB simulations. Finally, we have calculated an optimal number of secondary users to maximize the average channel throughput for different fusion rules.
Istarla Rahul Dev, S. Anuradha, and M. Ranjeeth
IEEE
In Cooperative spectrum sensing (CSS) network, cooperation among multiple CRs is present, they will exchange and share the information among them so that detection performance will be improved. In this paper, network utility function (NUF) performance is estimated for effective utilization of radio spectrum. Performance is evaluated over fading channels using conventional energy detector (CED) and improved energy detector (IED) schemes in CSS network. Total error rate (TER) value also calculated to identify fading channel gives minimum error value. Finally simulations are drawn for the evaluation of NUF and TER performance over fading channels using CED and an IED schemes.
M. Ranjeeth and S. Anuradha
IEEE
In order to utilize the available spectrum efficiently, the CR technology makes use of the spectrum holes in the absence of the licensed user using cooperative spectrum sensing (CSS) network. For an efficient utilization of radio spectrum and to improve the detection probability, network utility function (NUF) should be maximized. In this paper, NUF performance is analyzed using the multiple antennas at each CR with an improved energy detector in CSS network. An error is considered in reporting channel of CSS network. The performance comparison between error free and error present reporting channel also provided using the MATLAB simulations. Finally, network utility function analysis is evaluated using $\\boldsymbol{k}=1+\\boldsymbol{n}$ and $\\boldsymbol{k}=\\boldsymbol{N}-\\boldsymbol{n}$ fusion rules at FC over Rayleigh and Weibull fading channels. The NUF performance is evaluated for different values of thresholds, error rates in reporting channel, and sensing channel SNR values. Novel missed detection probability expression is derived in Weibull fading channel.
M. Ranjeeth and S. Anuradha
Springer Science and Business Media LLC
M. Ranjeeth, S. Anuradha, and Srinivas Nallagonda
Springer Science and Business Media LLC
Ranjeeth Mamidi and Anuradha Sundru
Elsevier BV
M. Ranjeeth, S. Anuradha, and Srinivas Nallagonda
Springer Science and Business Media LLC
M. Ranjeeth and S. Anuradha
Springer Science and Business Media LLC
M. Ranjeeth, , Srinivas Nallagonda, S. S.Anuradha, , and
International Hellenic University
In this paper, performance analysis for optimization of cooperative spectrum sensing (CSS) network in Nakagami-m and Weibull fading environments and comparison between them are presented. First, we derive the novel analytic expressions for probabilities of missed detection and false alarm for CSS network in both fading channels, assuming improved energy detector (IED) and selection combining (SC) diversity at each cognitive radios (CRs). Next, we optimize the network parameters such as number of CRs, energy detector arbitrary parameter, and normalized detection threshold at CR to obtain the optimal performance of CSS network. The impacts of several network parameters like: multiple antennas at each CR, number of CRs in CSS network, Nakagami and Weibull fading parameters, and sensing channel SNR on the performance of CSS network are investigated. The performance comparison between conventional and improved energy detectors has also been highlighted in this paper.
M. Ranjeeth, S. Anuradha, and Sipra Behera
IEEE
Spectrum sensing is an important task to find out the spectrum holes in a given radio spectrum. Spectrum sensing performance is improved with aid of multiple cognitive radios (CRs) in the network and each CR having multiple antennas. In this paper, we are considering that each CR having multiple antennas and improved energy detector (IED) is used for detection of primary user (PU). We have derived the novel expression for missed detection probability (Pm), closed form of equations to find out optimum value of number of CR users (Nopt), optimum value of normalized threshold value (λn, opt) and optimum value of arbitrary power of the received signals (popt) under Weibull fading channel. Performance is evaluated in terms of total error for various values of SNR & normalized threshold, optimizing the network parameters such as number of CR users (N), normalized threshold value (λ) and arbitrary power (p) of received signals of a PU. It is also observed that performance is improved by using multiple antennas at each CR. Comparison between Rayleigh fading and Weibull fading channels are also provided.
M. Ranjeeth, Sipra Behera, and S. Anuradha
IEEE
Spectrum sensing is an important task to find out the spectrum holes in a given radio spectrum. Spectrum sensing performance is improved with aid of multiple Cognitive Radios (CRs) in the network and each CR having multiple antennas. In this paper, we are considering that each CR having multiple antennas and improved energy detector (IED) is used for detection of primary user (PU). We have derived the novel expressions for probability of false alarm (Pf), missed detection probability (Pm), closed form of equations for optimum value of number of CR users (Nopt) and normalised threshold value (λopt) under Nakagami-m fading channel. Performance is evaluated in terms of total error for various values of SNR & normalized threshold, optimizing the network parameters such as number of CR users (N) and normalized threshold value (λ). It is also observed that performance is improved by using multiple antennas at each CR. Comparison between Rayleigh fading and Nakagami-m fading channels are also provided.
S. Anuradha, Sipra Behera, and M. Ranjeeth
IEEE
Spectrum sensing is a key function of cognitive radio to prevent the harmful interference with licensed users and identify the available spectrum for improving the spectrum utilization. In Spectrum Sensing, function of secondary users (SUs) is to detect the spectrum holes. However, in practice detection performance is often compromised with multipath fading, shadowing and receiver uncertainty issues. To mitigate the impact of these issues, cooperative spectrum sensing (CSS) is considered as an effective method to improve the detection performance by exploiting spatial diversity. In the current work centralized CSS is considered where all the SUs transmit their locally sensed information to fusion center (FC) and final decision is made by using soft-decision methods (SLC, SC, MRC) using energy detector (ED) at each CR as detection scheme. In this multi-path fading scenario with flat fading for narrowband spectrum sensing received SNR, total error probability, probability of false alarm, threshold value are considered as variable parameters in CSS. The current work focuses on performance of CSS, selecting a suitable threshold value for detection of primary user with minimum total error probability using diversity techniques and receiver operatting characteristics curves are also provided for various diversity techniques under different fading channels.
M. Ranjeeth, Sipra Behera, Srinivas Nallagonda, and S. Anuradha
IEEE
In this paper, an optimized cooperative spectrum sensing (CSS) network, in which each cognitive radio (CR) uses multiple antennas and an improved energy detector is proposed. The performance is evaluated by optimizing the network parameters such as number of CR users and normalized detection threshold. We have derived the suitable expressions for optimum value of normalized threshold in Rayleigh fading channel for single and multiple antenna case and optimum number of CRs for both AWGN and Rayleigh fading channels. Finally, optimal values of number of CRs and normalized detection threshold is calculated for different values of average sensing channel SNR, normalized threshold, and multiple antennas at each CR. Comparison between conventional energy detector (CED) and improved energy detector (EED) is also provided.
M. Ranjeeth and S. Anuradha
IEEE
Performance of cooperative spectrum sensing with hard decision fusion technique (majority logic) has been evaluated under Hoyt fading environment with the application of censoring scheme. In this paper we have considered Hoyt fading in both reporting channel (R-channel) and sensing channel (S-channel). In a cooperative spectrum sensing (CSS) scheme, the detection primary user (PU) activity is improved by eliminating the heavily faded cognitive radio (CR) users. CRs which are heavily faded those are eliminated by using censoring scheme in the R-channel. Rank based censoring scheme is used to censors the CRs in the presence of Hoyt fading in both perfect and imperfect channels. A hard decision based fusion technique called majority logic rule is considered at the fusion center (FC) to evaluate the performance using missed detection probability (Qm) and total error probability (Qm + Qf). This has been performed in both perfect and imperfect channels by varying the network parameters like: probabilities of false alarm (Qf), R-channel SNR, S-channel SNR and Hoyt fading parameter (q).
M. Ranjeeth and S. Anuradha
Springer International Publishing
M. Ranjeeth
IEEE
Cognitive radio (CR) technique is useful for to know the uses of radio spectrum. CR is used to sense the spectrum periodically to know the primary user activity in fading environment. Cooperation among multiple CRs helps to enhance the reliability of detection of the primary user (PU), to overcome the unreliable decision by a single CR due to channel uncertainties. Along with the Co-operation of multiple users, diversity techniques are often used to reduce the fading the effect as well as to increase the detection probability. In this paper, we have consider first with no diversity case, and extended to the square-law combining (SLC) diversity technique when wireless users experience different fading channels like (Rayleigh, Rician, Nakagami, Hoyt and Weibull) in the communication channel. The method used in this is, Cooperative spectrum sensing (CSS) with Energy detection over various fading channels using SLC diversity scheme. Finally, performance evaluation is exhibited using receiver operating characteristics (ROC) curves which are drawn between Pf vs Pd for different numbers of diversity branches, various values of average SNRs, time band width product and different values of fading parameter. It is observed from the simulation is that the Weibull fading performance is better than other fading channels while SLC diversity is used.