Muhammad Waleed Pasha¹, Mir Yasir Umair¹, Alina Mirza^1,*, Faizan Rao¹, Abdul Wakeel¹, Safia Akram¹, Fazli Subhan², Wazir Zada Khan³

CMC-Computers, Materials & Continua, Vol.69, No.2, pp. 1631-1652, 2021, DOI:10.32604/cmc.2021.018205

Abstract Due to the inability of the Global Positioning System (GPS) signals to penetrate through surfaces like roofs, walls, and other objects in indoor environments, numerous alternative methods for user positioning have been presented. Amongst those, the Wi-Fi fingerprinting method has gained considerable interest in Indoor Positioning Systems (IPS) as the need for line-of-sight measurements is minimal, and it achieves better efficiency in even complex indoor environments. Offline and online are the two phases of the fingerprinting method. Many researchers have highlighted the problems in the offline phase as it deals with huge datasets and validation of Fingerprints without pre-processing of… More >

Dah-Jing Jwo^*, Jia-Chyi Wu, Kuan-Lin Ho

CMC-Computers, Materials & Continua, Vol.69, No.1, pp. 555-574, 2021, DOI:10.32604/cmc.2021.018320

Abstract This paper investigates performance improvement via the incorporation of the support vector machine (SVM) into the vector tracking loop (VTL) for the Global Positioning System (GPS) in limited satellite visibility. Unlike the traditional scalar tracking loop (STL), the tracking and navigation modules in the VTL are not independent anymore since the user’s position can be determined by using the information from other satellites and can be predicted on the basis of the states of the user. The method proposed in this paper makes use of the SVM to bridge the GPS signal and prevent the error growth due to signal… More >

Dah-Jing Jwo^*, Meng-Hsien Hsieh

CMC-Computers, Materials & Continua, Vol.68, No.2, pp. 1785-1805, 2021, DOI:10.32604/cmc.2021.017225

Abstract In this paper, both the integrity monitoring and fault detection and exclusion (FDE) mechanisms are incorporated into the vector tracking loop (VTL) architecture of the Global Positioning System (GPS) receiver for reliability enhancement. For the VTL, the tasks of signal tracking and navigation state estimation no longer process separately and a single extended Kalman filter (EKF) is employed to simultaneously track the received signals and estimate the receiver’s position, velocity, etc. In contrast to the scalar tracking loop (STL) which utilizes the independent parallel tracking loop approach, the VTL technique is beneficial from the correlation of each satellite signal and… More >

Dah-Jing Jwo^1,*, Jen-Hsien Lai²

CMC-Computers, Materials & Continua, Vol.67, No.3, pp. 2883-2898, 2021, DOI:10.32604/cmc.2021.015102

Abstract This paper investigates the minimum error entropy based extended Kalman filter (MEEKF) for multipath parameter estimation of the Global Positioning System (GPS). The extended Kalman filter (EKF) is designed to give a preliminary estimation of the state. The scheme is designed by introducing an additional term, which is tuned according to the higher order moment of the estimation error. The minimum error entropy criterion is introduced for updating the entropy of the innovation at each time step. According to the stochastic information gradient method, an optimal filer gain matrix is obtained. The mean square error criterion is limited to the… More >

Ayesha Javed¹, Mir Yasir Umair^1,*, Alina Mirza¹, Abdul Wakeel¹, Fazli Subhan², Wazir Zada Khan³

CMC-Computers, Materials & Continua, Vol.67, No.2, pp. 1781-1799, 2021, DOI:10.32604/cmc.2021.015229

Abstract With the advent and advancements in the wireless technologies, Wi-Fi fingerprinting-based Indoor Positioning System (IPS) has become one of the most promising solutions for localization in indoor environments. Unlike the outdoor environment, the lack of line-of-sight propagation in an indoor environment keeps the interest of the researchers to develop efficient and precise positioning systems that can later be incorporated in numerous applications involving Internet of Things (IoTs) and green computing. In this paper, we have proposed a technique that combines the capabilities of multiple algorithms to overcome the complexities experienced indoors. Initially, in the database development phase, Motley Kennan propagation… More >

Qi Wang^1,2,3,*, Changsong Yang^2,3,5, Yuxiang Wang^1,2,3, Shao-en Wu⁴

Intelligent Automation & Soft Computing, Vol.26, No.6, pp. 1433-1442, 2020, DOI:10.32604/iasc.2020.012759

Abstract To improve the positioning accuracy of farming vehicle in precision agriculture, an integrated positioning system is proposed based on Global Navigation Satellite System (GNSS)/Strapdown Inertial Navigation System (SINS)/Wireless Sensor Networks (WSN) with low cost and high reliability. The principles of commonly used localization technologies in vehicle positioning are compared and the Received Signal Strength Indication (RSSI) based measurement method is chosen as the integrated positioning system for information fusion considering the complexity of the algorithm, positioning accuracy and hardware requirements in the application scenario. The research of wireless signal propagation loss model of farmland environment was conducted. A set of… More >

Dah-Jing Jwo^*

CMC-Computers, Materials & Continua, Vol.66, No.2, pp. 2105-2126, 2021, DOI:10.32604/cmc.2020.014241

Abstract In this paper, the Global Positioning System (GPS) interferometer provides the preliminarily computed quaternions, which are then employed as the measurement of the extended Kalman filter (EKF) for the attitude determination system. The estimated quaternion elements from the EKF output with noticeably improved precision can be converted to the Euler angles for navigation applications. The aim of the study is twofold. Firstly, the GPS-based computed quaternion vector is utilized to avoid the singularity problem. Secondly, the quaternion estimator based on the EKF is adopted to improve the estimation accuracy. Determination of the unknown baseline vector between the antennas sits at… More >

Dah-Jing Jwo^{1, *}

CMC-Computers, Materials & Continua, Vol.65, No.2, pp. 993-1014, 2020, DOI:10.32604/cmc.2020.011592

Abstract The Global Positioning System (GPS) offers the interferometer for attitude determination by processing the carrier phase observables. By using carrier phase observables, the relative positioning is obtained in centimeter level. GPS interferometry has been firstly used in precise static relative positioning, and thereafter in kinematic positioning. The carrier phase differential GPS based on interferometer principles can solve for the antenna baseline vector, defined as the vector between the antenna designated master and one of the slave antennas, connected to a rigid body. Determining the unknown baseline vectors between the antennas sits at the heart of GPS-based attitude determination. The conventional… More >

Lin Zhao¹, Xiaobo Chen^{1, 2, *}, Jianhua Cheng¹, Lianhua Yu³, Chengcai Lv⁴, Jiuru Wang⁵

CMC-Computers, Materials & Continua, Vol.64, No.2, pp. 1005-1023, 2020, DOI:10.32604/cmc.2020.010290

Abstract This paper addresses the problem of assessing and optimizing the acoustic positioning system for underwater target localization with range measurement. We present a new three-dimensional assessment model to evaluate the optimal geometric beacon formation whether meets user requirements. For mathematical tractability, it is assumed that the measurements of the range between the target and beacons are corrupted with white Gaussian noise with variance, which is distance-dependent. Then, the relationship between DOP parameters and positioning accuracy can be derived by adopting dilution of precision (DOP) parameters in the assessment model. In addition, the optimal geometric beacon formation yielding the best performance… More >