Inmarsat Broadband Global Area Network Research Articles

A Circularly Polarized Low-Cost Flat Panel Antenna Array With a High Impedance Surface Meta-Substrate for Satellite On-the-Move Medical IoT Applications

A 1 ×3 linear antenna array consisting of Quad-Arm Curl antenna with a High impedance surface (QACH) is presented. We believe that it is the first linear phased array solution which can provide 360° azimuth coverage. This array has been designed to operate at the L-band (1.518-1.675 GHz) and generate right-hand circularly polarized radiation to primarily target the Inmarsat Broadband Global Area Network (BGAN) satellite constellation. The metamaterial structure integrated into each antenna element allows a low-profile height of 17.2 mm ( λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1.597</sub> /10.9). Since the curl element has wideband characteristics, the array is able to provide shared aperture functionality. The array guarantees high-gain beam steering for low elevation angles (up to θ = 70 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> from the zenith) with an average gain of 7.96 dBic at θ = 70 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> . In comparison, to achieve an equivalent high gain a conventional 4 × 5 patch array would be required (three elements versus 20 elements). This means that the proposed array requires 80% fewer phase shifters, amplifiers, and low-noise amplifiers (LNAs). This translates to a crucial commercial advantage in relation to the manufacturing cost. This development can lead to disruption of the existing Satcom market by lowering the barrier-to-entry for customers looking for a mass deployable, low-cost Internet of Things (IoT) on Satcom solution.

Ambiguity function of Inmarsat BGAN signal for radar application

The Inmarsat Broadband Global Area Network (BGAN) L-band downlink signal from a radar viewpoint is studied. The signal is modelled and its ambiguity function (AF) is analysed and the AF is compared with that of the real recorded signal. It is shown that the AF of a single Inmarsat channel has an interference floor of −40 dB for 80 ms integration time. The AF of the Inmarsat BGAN signal is improved by combining multiple frequency channels with channel overlap.

A pre‐emption framework for UMTS compatible satellite system supporting multimedia traffic

SummaryThe pre‐emption procedure is an important part of the radio resource management when dealing with the emergency traffic. It allows resources to be allocated to higher priority connections by pre‐empting lower priority connections. The provision of the pre‐emption mechanism becomes much more important in the case of satellite systems such as the Inmarsat Broadband Global Area Network system, which aids in providing the communication during a catastrophe. This paper focuses on the pre‐emption framework for a Universal Mobile Telecommunications System‐based satellite systems. Three algorithms have been proposed, Greedy, SubSetSum and Fuzzy pre‐emption algorithm. Extensive simulations are carried out for the three algorithms, and their performances are compared against each other. Simulation results show that the Fuzzy pre‐emption algorithm performs better than the other two algorithms. Copyright © 2014 John Wiley &amp; Sons, Ltd.

An Inmarsat BGAN Terminal Patch Antenna Array With Unequal Input Impedance Elements and Conductor-Backed ACPW Series-Feed Network

A novel 2 × 2 sequentially rotated patch antenna array with unequal input impedance elements and a conductor-backed asymmetric coplanar waveguide (ACPW) series-feed network is proposed. The corner truncated patch element is fed by a three-dimensional meander strip, which can easily control the input impedance and has slight effects on the radiation performance. Compared to microstrip-line feed networks, the radiation loss of the proposed feed network is lower. Furthermore, the maximum characteristic impedance of transmission lines in the proposed feed network is 91.2 Ohm. As a result, it can be easily realized with printed circuit board (PCB) techniques. The measured results show that the proposed antenna array has an impedance bandwidth (VSWR <; 1.5) of about 40.5% (1244-1876 MHz), a 3-dB axial ratio (AR) bandwidth of about 25.6% (1412-1826 MHz), and a gain-level larger than 11.6 dBi across the broadband global area network (BGAN) operating bands. Therefore, the proposed antenna array can be a good candidate for Inmarsat BGAN portable terminal applications.

A wideband circular polarization antenna for portable INMARSAT BGAN terminal applications

AbstractA low profile, wideband, and portable antenna has been designed and fabricated for Inmarsat broadband global area network (BGAN) land mobile terminal applications. The purpose of the antenna was to provide a low‐cost and easy‐fabricated solution with wide bandwidth and high performance. The proposed antenna is composed of the stacked corner‐truncated patches with sequential rotation oblique feed and a serial feeding network. Good antenna characteristics are achieved over the BGAN operating bands. The measurement results for return loss, gain, axial ratio, and radiation pattern confirm the integrity of the simulation results. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2354–2357, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24643

Real time sea level data transmission from tide gauges for tsunami monitoring and long term sea level rise observations

The authors present the development and implementation of a ‘tsunami enabled’ tidegauge which allows real time data to be returned from almost anywhere on Earth. At itscentre is a low power, embedded Linux platform, which performs the data logging andcommunications. This is attached to a radar and pressure sensors that are queried overa serial interface. Telemetry is through the Inmarsat Broadband Global Area Network(BGAN) system which allows a bi-directional broadband connection over Ethernet,permitting remote reconfiguration when required, and faster, more frequent tide gaugedata. Data transmission is over an internet connection with files containing one minutevalues from three sensors returned every five minutes

Efficient IP‐multicast via Inmarsat BGAN, a 3GPP satellite network

AbstractThis paper outlines a number of challenges associated with supporting IP‐multicast services efficiently across the Inmarsat Broadband Global Area Network (BGAN) 3GPP‐based satellite network operating over the Imarsat‐4 satellite constellation. The paper presents a network architecture that extends the 3GPP reference architecture to allow IP‐multicast to be delivered when the Core Network is in a 3GPP Release‐4 (non‐MBMS compliant) configuration.This paper further extends the service and system concepts defined in 3GPP MBMS to provide improved flexibility and accountability, and improved scalability and efficiency when operating with the Inmarsat‐4 BGAN TDM/TDMA air interface.This paper describes a number of radio resource management techniques that were deployed in a test system and the validation testing that was undertaken to support multimedia distribution and VoIP‐based netted communications applications. The tuning of application and system behaviour to achieve acceptable performance is described in outline. Copyright © 2007 John Wiley &amp; Sons, Ltd.

What exactly is airborne personal communications?

The paper discusses BGAN (broadband global area network) service from Inmarsat carried by their latest 14 satellites allows data rates of up to about 500kbps per channel in both uplink and downlink. In view of the greater capability and more flexible use, costs can be dramatically reduced, thereby bringing affordable access to many more people. The Thales satellite communications transmitter receiver for the satellite link. The equipment is designed to be compact while providing the required capability for the Inmarsat BGAN system.