05-03-2013, 10:12 AM
MOBILE COMMUNICATION VIA STRATOSPHERE -A REVOLUTION IN THE WIRELESS COMMUNICATIONS
[attachment=52582]
ABSTRACT
Today we are in danger due to health hazards caused by mobile radiation. Recent surveys and experts confirmed that continuous exposure to mobile radiation causes brain tumors, cancers, headache and stress feeling. Not only human beings but also birds, animals are facing lot of problems due to mobile radiation exposure ,but many Mobile Network operators establishing Antennas in and around us without meeting the guidelines of Government. Then how to reduce the effect of the radiation caused by the antennas, where to construct these antennas ? The answer is somewhat crazy i.e., in SKY. Recent research and experiments by NASA and JAPAN suggested that we can establish these antennas in the SKY i.e., in stratosphere where the velocity of wind is 10-15 miles/hr. These antennas in sky are termed as HAPS (High Altitude Platform stations). These platforms are established above the region of air-traffic control in stratosphere and are used not only for mobile communication purpose but also in Broadband services, monitoring volcanic eruptions, flood effected regions with less investment compared to Satellites sent to outer space.
INTRODUCTION
The HAPS, known also as HALE (High Altitude Long Endurance) stations or SPR (Stratospheric Platform Radio) are reusable unmanned aeronautical vehicles (UAV) at stratospheric altitudes that offer an alternative to the terrestrial and satellite telecommunication systems. They promise access to modern telecommunication services in many situations at lower costs and shorter deployment times. The HAPS can equally well be used in both, mobile and fixed services. High antenna masts have been used since the beginning of radio, and satellite technology has put the antennas at altitudes of hundreds or even thousands kilometers. The HAPS aim at exploiting potential benefits of intermediate altitudes between those used by the terrestrial and satellite technologies. The European Space Agency (ESA) and International Telecommunication Union (ITU) have been involved in this area since the late 1990s. The Wireless World Research Forum (WWRF), created to formulate visions on strategic future research directions and to generate, identify, and promote research, has included HAPS into their program in 2001. With all that involvement, the perspectives of practical application of that technology are becoming realistic.
On a basis of various concepts proposed, the ITU has elaborated a common understanding of HAPS. Accordingly, the HAPS are understood as stations “located on an object at an altitude of 20 to 50 km and a specified, nominal, fixed point relative to the Earth
TheStratosphere
The stratosphere is a part of the Earth’s atmosphere, which consists of several distinct layers. The lowest one is the troposphere. It extends from the Earth’s surface to the tropopause about 10 to 18 km in altitude, depending on the season and geographical position. In the troposphere, the air temperature generally decreases with height. The air pressure decreases from about 1000 hPa at the sea level to about 100 hPa at the tropopause altitude. Approximately 80% of the total air mass resides here, and almost all weather phenomena.
The stratosphere is the next layer, extending from the tropopause to the stratopause at about 50 km. The ozone layer resides here and more than 99% of the total air mass is concentrated in the first 40 km from the Earth’s surface. The stratosphere is characterized by a high static stability associated with increase of temperature with height. The pressure decreases further to reach about 1 hPa at the stratopause.
SOLAR PLATFORMS
The Sun is the most natural energy source for stratospheric platforms located above clouds. The efficiency of photovoltaic cells has been significantly improved, making solar energy an attractive alternative to power high altitude platforms. As quasi-stationary stations experience the same day-night cycle as any point on the Earth surface, solar cells can produce electricity only 12-hours a day. Energy drawn from solar radiation during the daytime must thus be stored for use at night to assure continuous operation of station. The regenerative fuel cells (RFC) which use water as fuel are to be used for that purpose. During the day, the water is decomposed into hydrogen and oxygen in the electrolytic process. At night, the chemical reactions run backwards producing electricity and water with no pollution.
Concluding Remarks
The High Altitude Platform Stations are expected to provide, in a cost-effective manner, a multitude of telecommunication and other services over large areas. Known also as stratospheric repeaters, they may operate individually or be interconnected with other similar HAPS and/or terrestrial and satellite-based stations. Compared to terrestrial telecommunication systems, the HAPS offer high signal arrival angle, largely unobstructed signal path, and large coverage area - like satellite-based systems but at lower cost. They can use most of conventional base station technology and terminal equipment.
[attachment=52582]
ABSTRACT
Today we are in danger due to health hazards caused by mobile radiation. Recent surveys and experts confirmed that continuous exposure to mobile radiation causes brain tumors, cancers, headache and stress feeling. Not only human beings but also birds, animals are facing lot of problems due to mobile radiation exposure ,but many Mobile Network operators establishing Antennas in and around us without meeting the guidelines of Government. Then how to reduce the effect of the radiation caused by the antennas, where to construct these antennas ? The answer is somewhat crazy i.e., in SKY. Recent research and experiments by NASA and JAPAN suggested that we can establish these antennas in the SKY i.e., in stratosphere where the velocity of wind is 10-15 miles/hr. These antennas in sky are termed as HAPS (High Altitude Platform stations). These platforms are established above the region of air-traffic control in stratosphere and are used not only for mobile communication purpose but also in Broadband services, monitoring volcanic eruptions, flood effected regions with less investment compared to Satellites sent to outer space.
INTRODUCTION
The HAPS, known also as HALE (High Altitude Long Endurance) stations or SPR (Stratospheric Platform Radio) are reusable unmanned aeronautical vehicles (UAV) at stratospheric altitudes that offer an alternative to the terrestrial and satellite telecommunication systems. They promise access to modern telecommunication services in many situations at lower costs and shorter deployment times. The HAPS can equally well be used in both, mobile and fixed services. High antenna masts have been used since the beginning of radio, and satellite technology has put the antennas at altitudes of hundreds or even thousands kilometers. The HAPS aim at exploiting potential benefits of intermediate altitudes between those used by the terrestrial and satellite technologies. The European Space Agency (ESA) and International Telecommunication Union (ITU) have been involved in this area since the late 1990s. The Wireless World Research Forum (WWRF), created to formulate visions on strategic future research directions and to generate, identify, and promote research, has included HAPS into their program in 2001. With all that involvement, the perspectives of practical application of that technology are becoming realistic.
On a basis of various concepts proposed, the ITU has elaborated a common understanding of HAPS. Accordingly, the HAPS are understood as stations “located on an object at an altitude of 20 to 50 km and a specified, nominal, fixed point relative to the Earth
TheStratosphere
The stratosphere is a part of the Earth’s atmosphere, which consists of several distinct layers. The lowest one is the troposphere. It extends from the Earth’s surface to the tropopause about 10 to 18 km in altitude, depending on the season and geographical position. In the troposphere, the air temperature generally decreases with height. The air pressure decreases from about 1000 hPa at the sea level to about 100 hPa at the tropopause altitude. Approximately 80% of the total air mass resides here, and almost all weather phenomena.
The stratosphere is the next layer, extending from the tropopause to the stratopause at about 50 km. The ozone layer resides here and more than 99% of the total air mass is concentrated in the first 40 km from the Earth’s surface. The stratosphere is characterized by a high static stability associated with increase of temperature with height. The pressure decreases further to reach about 1 hPa at the stratopause.
SOLAR PLATFORMS
The Sun is the most natural energy source for stratospheric platforms located above clouds. The efficiency of photovoltaic cells has been significantly improved, making solar energy an attractive alternative to power high altitude platforms. As quasi-stationary stations experience the same day-night cycle as any point on the Earth surface, solar cells can produce electricity only 12-hours a day. Energy drawn from solar radiation during the daytime must thus be stored for use at night to assure continuous operation of station. The regenerative fuel cells (RFC) which use water as fuel are to be used for that purpose. During the day, the water is decomposed into hydrogen and oxygen in the electrolytic process. At night, the chemical reactions run backwards producing electricity and water with no pollution.
Concluding Remarks
The High Altitude Platform Stations are expected to provide, in a cost-effective manner, a multitude of telecommunication and other services over large areas. Known also as stratospheric repeaters, they may operate individually or be interconnected with other similar HAPS and/or terrestrial and satellite-based stations. Compared to terrestrial telecommunication systems, the HAPS offer high signal arrival angle, largely unobstructed signal path, and large coverage area - like satellite-based systems but at lower cost. They can use most of conventional base station technology and terminal equipment.