A Novel Wormy Cellular Structure for High Altitude Platforms Mobile Communications (original) (raw)

A Novel Design of Arbitrary Shaped Cells for Efficient Coverage from High Altitude Platforms

2008

This paper proposes a novel beamforming technique to form an arbitrary-shaped cell for the high altitude platforms (HAPs) mobile communications. The new technique is based on pattern summation of individual low-sidelobe narrow-beams which constitute the desired cell pattern weighted by an amplitude correcting function. The new cell pattern can be adapted to cover the main highways forming worm-shaped cells which may cover the highway for long distances up 100 km and it will has an important role in reducing frequent handoffs and signaling traffic of location updating from moving users over the long highways.

A Novel Beamforming Technique for Highways Coverage Using High-Altitude Platforms

2007

This paper proposes a novel beamforming technique to form an arbitrary-shaped cell for the high-altitude platforms (HAPs) mobile communications. The new technique is based on pattern summation of individual low-sidelobe, narrow beams which constitute the desired cell pattern weighted by an amplitude correcting function. The new cell pattern can be adapted to cover the main highways forming worm-shaped cells which may cover the highway for long distances up to 100 km and it will have an important role in reducing frequent handoffs and signaling traffic of location updating from moving users over the long highways.

ResearchLetter A Novel Beamforming Technique for Highways Coverage Using High-Altitude Platforms

2000

This paper proposes a novel beamforming technique to form an arbitrary-shaped cell for the high-altitude platforms (HAPs) mobile communications. The new technique is based on pattern summation of individual low-sidelobe, narrow beams which constitute the desired cell pattern weighted by an amplitude correcting function. The new cell pattern can be adapted to cover the main highways forming worm-shaped cells which may cover the highway for long distances up to 100 km and it will have an important role in reducing frequent handoffs and signaling traffic of location updating from moving users over the long highways.

Optimization of Beams Directions for High Altitude Platforms Cellular Communications Design

2006

Cellular communications using high altitude platforms will predominate the existing conventional terrestrial or satellite cellular systems but requires some optimization especially in the, radio coverage cellular design. In this paper either spot-beam antennas or antenna phased arrays are used in the radio coverage which is optimized in directing their beams to satisfy mostly uniform cellular layout with minimal coverage problems such as coverage gaps between cells or excessive cells overlap

Effect of Antenna Beam Pattern and Layout on Cellular Performance in High Altitude Platform Communications

Wireless Personal Communications, 2005

High Altitude Platforms may offer high spectrum efficiency by deploying multi-beam, multi-cell communications networks. The properties of the antennas carried by the HAP payload are key to the effective exploitation of these benefits. This paper compares different models for the antenna sidelobe region and quantifies, in each case, the carrier to interference ratio for a 3 channel re-use plan. Networks of 121 and 313 cells are compared. We show how the ITU recommended pattern for the 47/48 GHz band leads to pessimistic results compared to an adapted pattern which fits that of measured data for an elliptic beam lens antenna. The method is then extended to consider other radiation patterns. Spectrum sharing issues are explored with reference to further ITU recommendations and comparison with measurement data. Finally, an ITU type cellular layout which uses the same antenna for each cell is compared to an alternative hexagonal layout where each cell has equal size.

A novel cellular structure for stratospheric platform mobile communications

Proceedings of the Nineteenth National Radio Science Conference, 2002

A move1 cellular structure is proposed for the ambitious stratospheric platform mobile communications. The innovated structure adopts a multibeam scanning antenna array to create ringshaped cells instead of the classical honey cells. This helps in avoiding the impact of positional instability especially the rotational motion of the platform around its vertical axis. Furthermore the transmitted power is reduced as well as the handover and location updating rates. The adaptation of the cell area for traffic balancing is easier than using the traditional hexagonal one. The w-a.etry of the ring cell is analyzed in order to investigate the main parameters affecting the S Y S b performance such as the beam visiting time and the beam-scanning rate.

High-Altitude Platforms Cellular System for Sparsely Populated Areas

International Journal of Computer Network and Information Security, 2014

In this paper, the cellular communications using high altitude platform (HAP) will be discussed including the coverage analysis and design. The cells are analyzed showing the main parameters affecting its shape, layout and area which are important in the cellular design stage. This HAP cellular system is very important to cross the gap of difficult extension of ground infrastructure especially for sparsely populated areas needing communications services. The system design is explained where the footprint of the HAP cell is demonstrated and the overall cellular layout is established. As a case study, the coverage of the HAP cellular system is proved to cover some areas in the Kingdom of Saudi Arabia (KSA) using several scenarios such as populated as well as long highways passing through desert areas. The HAP cells are generated using spot-beam antennas which are practically candidate. The simulation results show that a single HAP can provide hundreds of microcells for urban areas while covering very long highways that can extend to several hundreds of kilometers which is very useful in covering the long highways linking sparsely separated cities in KSA.

Handoff Study of Ring Shaped Cellular Configuration Designed for High Altitude Platform Communications

International Journal of Computer Applications, 2014

In this paper, the concentric ring shaped cellular configuration is designed for High Altitude Platforms (HAPs). An one dimensional (1D) vertical linear antenna array is used to generate this configuration. The effect of different types of HAP mobility models, e.g. drift, random walk, and reflection has been examined. The possibility of reducing the need for mechanical stabilization via handoff techniques is demonstrated through the study of handoff, dropping, and blocking probabilities.

Flat-Top Ring-Shaped Cell Design for High-Altitude Platform Communications

2013

In this paper, a new design for ring-shaped cells is introduced where to improve the power distribution and carrier-to-interference ratio (CIR) over the cell area. The designed cell has flat-top radiation pattern with minimal ripples in the service area while the out-of-cell area has lower radiation levels. The new design utilizes two weighting functions applied to a vertical linear array; the first is responsible for the flat-top design and the second smoothes the pattern and reduces the sidelobe levels. The resulted power pattern has a uniform distribution over the cell stripe with as small as 0.25 dB ripples and a uniform CIR values greater than 43 dB within the cells which reduces the burden of power control and increases the immunity to propagation problems.

Enhancing the Capacity of Stratospheric Cellular Networks Using Adaptive Array Techniques

International Journal of Computer Network and Information Security, 2013

In this paper, the capacity of stratospheric cellular communications is improved by optimizing the amplitude feeding of the concentric rings array (CRA). The weighting profile of this array is chosen to be a cosine function raised to some power to control the beam pattern used in the cellular coverage. The power of this function is optimized to reduce the resulted sidelobe levels which increase the carrier-to-interference ratio (CIR) within the cells. It is found that increasing the power of the cosine function will reduce the sidelobe levels especially at lower number of elements in the innermost ring with a minor increase in beamwidth. For an innermost ring of 3 elements in a 10 rings CRA, a sidelobe level of 45 dB can be obtained below the mainlobe level. The simulation results show that a CIR of up to 38dB can be achieved and a minimum of 28dB at the cell borders is guaranteed with a 0.95 coverage ratio.