Delivering Extended Cellular Coverage and Capacity Using High-Altitude Platforms

Abstract

Interest in delivering cellular communication using a high-altitude platform (HAP) is increasing partly due to its wide coverage capability. In this paper, we formulate analytical expressions for estimating the area of a HAP beam footprint, average per-user capacity per cell, average spectral efficiency (SE) and average area spectral efficiency (ASE), which are relevant for radio network planning, especially within the context of HAP extended contiguous cellular coverage and capacity. To understand the practical implications, we propose an enhanced and validated recursive HAP antenna beam-pointing algorithm, which forms HAP cells over an extended service area while considering beam broadening and the degree of overlap between neighbouring beams. The performance of the extended contiguous cellular structure resulting from the algorithm is compared with other alternative schemes using the carrier-to-noise ratio (CNR) and carrier-to-interference-plus-noise ratio (CINR). Results show that there is a steep reduction in average ASE at the edge of coverage. The achievable coverage is limited by the minimum acceptable average ASE at the edge, among other factors. In addition, the results highlight that efficient beam management can be achieved using the enhanced and validated algorithm, which significantly improves user CNR, CINR, and coverage area compared with other benchmark schemes. A simulated annealing comparison verifies that such an algorithm is close to optimal.

Realization of 4 × 200 Gbps 4-QAM OFDM-OWC System Using Higher Order OAM Modes for HAP-to-Satellites Scenario

“…A study in [12] developed analytical expressions for analyzing the HAP relay footprint area, spectral efficiency, and capacity per user. Three distinct eavesdropping scenarios are presented and investigated for the security of physical layer performance in HAP systems.…”

“…OAM modes have proven strong in terabit-to-petabit scale potential transmission, and they have gained from a dozen to hundreds of percent spectral efficiency over OWC links [11]. Despite the numerous benefits of OAM in OWC links, there are several predominant issues which were not discussed earlier using higher-order OAM modes in previous works for HAP scenarios in [12][13][14][15]. These major issues need to be addressed such as (1) OAM beams mode crosstalk owing to smaller differences among various modes, (2) receiver low power efficiency caused by very high order Laguerre-Gaussian (LG) modes in OAM, (3) mode leakage as a result of pointing errors, and (4) significant phase modulation when turbulence is present.…”

Low Altitude Satellite Constellation for Futuristic Aerial-Ground Communications

“…HAPs can be used for a variety of scenarios, including broadcast/multicast signals, extremely high-speed wireless connectivity, navigation and global positioning systems (GPS), intelligent transportation systems, surveillance, remote sensing, naval engineering, weather monitoring, emergency communications, and disaster management [22]. It is also capable of providing very high-speed backhaul links to reduce the continuously soaring traffic burden of cellular networks [30]. The purpose of creating B5G wireless systems and services is to provide seamless delivery of broadband multimedia applications across heterogeneous networks.…”

“…Today, conventional SATCOMs essentially make use of frequency bands in the range of 1 to 40 GHz. Due to low frequency band saturation, relatively higher frequency bands, those above 20 GHz, such as the Ka-band (27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40), have been explored to greater depths and degrees, as the Ka-band can provide stable broadband services [44]. Newer satellite networks should provide mobile satellite services (MSS) to be compatible with terrestrial mobile networks integrating 5G technology [12].…”