Nischal Adhikari - Academia.edu (original) (raw)

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Papers by Nischal Adhikari

The field of wireless communication has become an important part of electrical engineering underg... more The field of wireless communication has become an important part of electrical engineering undergraduate program. Due to developments in this field there is an increasing need for graduates with good understanding of wireless channels. However, the electromagnetic fields and radio propagation has been regarded as a dry and abstract field, due to difficulty of integrating tangible and realistic experiments into electrical engineering curriculum. Sometimes setting up a laboratory for these experiments could be very expensive. Therefore, a lot of time using simulation tools is a good alternative to examine and visualize the realistic problems. However, the available simulation software may require vast technical proficiency, which sometime impedes the inclination of students towards this area of study. In this paper we introduce a ray-tracing simulation tool that can be beneficial in teaching wave propagation and wireless communication. Wireless InSite®, from Remcom®, is a site-specific wireless channel simulation tool based on ray-tracing method. This paper introduces various feature of Wireless InSite such as how to import site-specific information from Google Maps, create three dimensional object files and manipulate them for creating a realistic environment, how to select different types of antennas and waveforms. Then an example is given and the stepby-step problem setting, execution and analysis of results are explained. This example or similar ones may be utilized as a laboratory assignment in the related curriculum.

2014 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM), 2014

Summary form only given. Dedicated Short Range Communication (DSRC) [1], an automotive communicat... more Summary form only given. Dedicated Short Range Communication (DSRC) [1], an automotive communication protocol, is popular for its potential application like Lane Changing Warning (LCW), Forward Collision Warning (FCW) in ensuring traffic safety and reducing traffic accidents. The major challenge in developing such application to provide a 360 degrees view of traffic status is to overcome the hurdle provided by the obstacles in form of buildings (in intersection), heavy vehicles (in case of overtaking), generally categorized as Non-Line-of-Sight (NLOS) scenarios [2]. In this work, we have used a vehicle as an obstacle between two other vehicles (at the transmitting and receiving ends). Antennas were placed at various locations on the vehicles' bodies. A total of 15 transmitters and receivers were spread out on the rear, center and front of two vehicles. The two vehicles were separated by two different distances: 10 meters and 15 meters, and the obstacle vehicle was positioned at ...

IEEE Antennas and Wireless Propagation Letters, 2016

In car-to-car (C2C) communication, it is very important to understand the channel behavior. To in... more In car-to-car (C2C) communication, it is very important to understand the channel behavior. To increase the channel capacity, multiple antennas might be used in the form of multiple-input-multiple-output (MIMO). The location of antennas on the car affects the capacity. A channel sounding system is used to study the vehicular channels in various environments, therefore it is important that the sounding system to be portable and of small form factor. We propose a sounding system based on software defined radio (SDR). The system was developed and used for measurement campaigns. The testbed was implemented, and two scenarios of measurements were performed with different street size and building proximity.

2014 IEEE Antennas and Propagation Society International Symposium (APSURSI), 2014

Channel capacity is an important parameter for any wireless system. In Car-to-Car (C2C) communica... more Channel capacity is an important parameter for any wireless system. In Car-to-Car (C2C) communication, the location of antennas on the car affects the capacity. To improve the capacity the concept of Multiple Input Multiple Output (MIMO) and antenna location is studied experimentally. A channel sounding system using Software Defined Radio (SDR) was developed and used for measurement campaigns. The study was performed in low and high traffic environments. The results were compared for different antenna locations.

2014 National Wireless Research Collaboration Symposium, 2014

In this paper, the physical layer for a multi-antenna vehicular communication channel has been in... more In this paper, the physical layer for a multi-antenna vehicular communication channel has been investigated considering the effects of antenna types, antennas' orientation and position through a ray-tracing simulation. The simulation software utilized is Wireless InSite® from Remcom Inc. Both static and dynamic scenarios are considered. Multiple transmitters and receivers were spread on the rear, center and front of two vehicles separated by 10m distance. A car with a height more than transmitting and receiving end car was placed in between them to study the vehicular channel behavior in complete Non-Line of Sight (N-LOS) scenarios. To simulate the dynamic scenarios, the response of each receiver with respect to each transmitter was analyzed at a static situation. Then, the entire set up (transmitting, receiving and blocking cars) was moved to a new position, to examine the variation in the Signal to Noise Ratio (SNR) as well as multipath contributions in the changes in channel capacity. Both Omni directional and directional antennas were studied. Different antenna orientations were adopted in the case of directive horn antennas to analyze the effect of antenna directivity on improving the channel efficiency. Furthermore, incorporating the concept of Multiple Input and Multiple Output (MIMO), antenna selection both at the transmitter and receiver sides were used to evaluate the channel capacity of a Vehicle to Vehicle (V2V) communication system in respect to antenna position and car locations.

The field of wireless communication has become an important part of electrical engineering underg... more The field of wireless communication has become an important part of electrical engineering undergraduate program. Due to developments in this field there is an increasing need for graduates with good understanding of wireless channels. However, the electromagnetic fields and radio propagation has been regarded as a dry and abstract field, due to difficulty of integrating tangible and realistic experiments into electrical engineering curriculum. Sometimes setting up a laboratory for these experiments could be very expensive. Therefore, a lot of time using simulation tools is a good alternative to examine and visualize the realistic problems. However, the available simulation software may require vast technical proficiency, which sometime impedes the inclination of students towards this area of study. In this paper we introduce a ray-tracing simulation tool that can be beneficial in teaching wave propagation and wireless communication. Wireless InSite®, from Remcom®, is a site-specific wireless channel simulation tool based on ray-tracing method. This paper introduces various feature of Wireless InSite such as how to import site-specific information from Google Maps, create three dimensional object files and manipulate them for creating a realistic environment, how to select different types of antennas and waveforms. Then an example is given and the stepby-step problem setting, execution and analysis of results are explained. This example or similar ones may be utilized as a laboratory assignment in the related curriculum.

2014 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM), 2014

Summary form only given. Dedicated Short Range Communication (DSRC) [1], an automotive communicat... more Summary form only given. Dedicated Short Range Communication (DSRC) [1], an automotive communication protocol, is popular for its potential application like Lane Changing Warning (LCW), Forward Collision Warning (FCW) in ensuring traffic safety and reducing traffic accidents. The major challenge in developing such application to provide a 360 degrees view of traffic status is to overcome the hurdle provided by the obstacles in form of buildings (in intersection), heavy vehicles (in case of overtaking), generally categorized as Non-Line-of-Sight (NLOS) scenarios [2]. In this work, we have used a vehicle as an obstacle between two other vehicles (at the transmitting and receiving ends). Antennas were placed at various locations on the vehicles' bodies. A total of 15 transmitters and receivers were spread out on the rear, center and front of two vehicles. The two vehicles were separated by two different distances: 10 meters and 15 meters, and the obstacle vehicle was positioned at ...

IEEE Antennas and Wireless Propagation Letters, 2016

In car-to-car (C2C) communication, it is very important to understand the channel behavior. To in... more In car-to-car (C2C) communication, it is very important to understand the channel behavior. To increase the channel capacity, multiple antennas might be used in the form of multiple-input-multiple-output (MIMO). The location of antennas on the car affects the capacity. A channel sounding system is used to study the vehicular channels in various environments, therefore it is important that the sounding system to be portable and of small form factor. We propose a sounding system based on software defined radio (SDR). The system was developed and used for measurement campaigns. The testbed was implemented, and two scenarios of measurements were performed with different street size and building proximity.

2014 IEEE Antennas and Propagation Society International Symposium (APSURSI), 2014

Channel capacity is an important parameter for any wireless system. In Car-to-Car (C2C) communica... more Channel capacity is an important parameter for any wireless system. In Car-to-Car (C2C) communication, the location of antennas on the car affects the capacity. To improve the capacity the concept of Multiple Input Multiple Output (MIMO) and antenna location is studied experimentally. A channel sounding system using Software Defined Radio (SDR) was developed and used for measurement campaigns. The study was performed in low and high traffic environments. The results were compared for different antenna locations.

2014 National Wireless Research Collaboration Symposium, 2014

In this paper, the physical layer for a multi-antenna vehicular communication channel has been in... more In this paper, the physical layer for a multi-antenna vehicular communication channel has been investigated considering the effects of antenna types, antennas' orientation and position through a ray-tracing simulation. The simulation software utilized is Wireless InSite® from Remcom Inc. Both static and dynamic scenarios are considered. Multiple transmitters and receivers were spread on the rear, center and front of two vehicles separated by 10m distance. A car with a height more than transmitting and receiving end car was placed in between them to study the vehicular channel behavior in complete Non-Line of Sight (N-LOS) scenarios. To simulate the dynamic scenarios, the response of each receiver with respect to each transmitter was analyzed at a static situation. Then, the entire set up (transmitting, receiving and blocking cars) was moved to a new position, to examine the variation in the Signal to Noise Ratio (SNR) as well as multipath contributions in the changes in channel capacity. Both Omni directional and directional antennas were studied. Different antenna orientations were adopted in the case of directive horn antennas to analyze the effect of antenna directivity on improving the channel efficiency. Furthermore, incorporating the concept of Multiple Input and Multiple Output (MIMO), antenna selection both at the transmitter and receiver sides were used to evaluate the channel capacity of a Vehicle to Vehicle (V2V) communication system in respect to antenna position and car locations.