High Altitude Platform based Wireless Network

Summer 2009

ICT

TUWien

Ha Yoon Song, Guestprofessor

song@ict.tuwien.ac.at

PSL

IPL

Ground station

Switch / Gateway

IP

HAP

Broadband Communications via High Altitude Platforms(HAPs) – A survey

S. Karapantazis and F.-N. Pavlidou

Introduction(1)High Altitude Platforms(HAPs)

Stratospheric Platforms(SPFs)

Height 17 ~ 22Km

from hot-air balloons

Advantage of

Satellite Communication System

Terrestrial Wireless System

Introduction(2)• Easy to deploy, incremental deploy• Flexibility, Reconfigurability• Low cost of operation (comparing to Satellites)• Low propagation delay• High Elevation!• Wide area coverage• Broadcast/Multicast• Mobility !

• BUT, Problems with• Monitoring of Station• Airship manufacturing• Antenna technology

Introduction(4)• HAPs for 3G+ system because of

• Easy to maintain• Easy to deploy• Lower path loss

• 4G : Satellite + HAPS = MBMS.

• Stand alone HAPs for low population with large area.

Aerial Vehicles, Key Issues and Spectrum Allocation

Three types

1) Propulsion + unmanned airships(balloons, aerostats)

2) High Altitude Long Endurance Platforms(HALE Platforms) Solar-powered unmanned aircraft

3) Manned aircraft(???)

Key Issues

Airship HOVERING

GPS

Diesel Motors + Solar powered

Spectrum Allocation

ITU allocates HAPs frequency with 48/47GHz + 600MHz

shared with satellite

OR for 3G, 2GHz

For broadband, fixed application 18-32GHz

Table 5.

Architectures and Services I-Network Design-

High reliability

Low power consumption

Lighter payload

Max 150KM footprint by ITU

Min. 5 degree of elevation

Recommended 15+ degree to avoid clutter

Architectures and Services(2) -Network Design-

Frequency Reuse

Cellular architecture

High Bandwidth for Broadband application

Fixed Channel Allocation(FCA)

Dynamic Channel Allocation(DCA)

HeliNet Network

CAPANINA

Architectures and Services(3) -Network Design-

Backhaul links, duplicated

High traffic for down link

Asymmetry to uplink

Multiple uplinks for backhaul station

Architectures and Services(4) -Network Design-

Macrocell and microcell architecture (Fig.12)

Rural macrocell (Fig.13)

Sectoring. (Fig.14) for system capacity

Architectures and Services(5) -Network Design-

Ring-shaped Cell Clustering (Fig. 15).

Coaxial Rings

Multi-beam, controllable antenna

Simpler handoff design

Cell scanning (Fig. 16)

Stratospheric radio-relay Maritime ( Fig.17 )

Architectures and Services -Capacity-

• Bandwidth• Cell size depends on Antenna• Directional Antenna• Interference (Fig.20)

Channel Modeling and Transmission Techniques( Transmission and Coding 1 )

HeliNet : QP,, QAM, M-PSK(starQAM), CPM, GMSK, MA-MSK)

Table 11

Elevation!

Antennas(1)

Requirements

1. High frequency for High bandwidth

2. High gain, directional antenna

3. Multibeam antenna with 100+ beams

4. Fig. 34 for footprint

5. Beam controllability

6. Low payload and low power

7. Reliability

Antennas(2)

Array of the antenna at 2.2Ghz, 21Km height

Wider array with high altitude, narrower array with high frequency

Multibeam Horn(MBH)

Digital Beamforming(DBF)

Table XⅡ

Applications and Related Projects(1) - Applications -

HAPs is able to RAPID DEPLOY

Olympic Game, Pop concert, Rescue management

Wideband Internet access, entertainment video, audio, videoconferencing, cellular telephony, digital network

Standalone HAP network

Supplementary network for other terrestrial network

Applications and Related Projects(2) - Applications -

• HAP can be combined with GSM spec easily• HAP with BASE STATION inside• HAP only with REPEATER inside• HAP with REPEATER communicates with

Reference station which is NOT GSM combatible

• HAP ability with GSM: Fig.45

• Remote control for HAP

Related Projects(1)

HeliNet: High Altitude Very Long Endurance unmanned solar aerodynamic platform

1. Broadband telecommunication services

2. Remote sensing

3. Navigation/local sation

Related Projects(2)• 2003/ 11 CAPANINA, 6th European Union’s Framework

HeliNet based

120Mbit/s

“smart roof” antenna over TRAIN

mm-wave band

free space-optic

• Also with• England• Korea• Japan• Sweden• US – watchdog ships also….• Australia

INTEGRATING USERSINTO THE WIDER BROADBAND

NETWORK VIA HIGH ALTITUDE PLATFORM

PEM

Introduction(1)

• Helinet(5th Frame work Programme) Scale size of HAP and 3 pilot application

1)Broadband communication

2)Environmental monitoring

3)Remote sensing• CAPANINA(6th) Low cost broadband technology Efficient integrated coverage

Introduction(2)

1. enable high-rate communication (120 Mbps) 2. 60Km + LOS for direct service

Introduction(3)

Identification of appropriate application and service and associated business model

Development of a system testbed

(near-term)

☞ fixed user, backhaul for WLAN..

(Longer-term) advanced mobile broadband wireless access

Broadband Application, Service, and Infrastructure

120Mb/s + 60Km + LOS Seamlessly integrate with other delivery

platform Communication standard

Application and Service Selection(1)

QOS parameter : delay, delay variation, packet loss

Application and Service Selection(2)

• HAP : end to end path

1) In isolation from any core network,

providing connectivity for private network.

(having few but high value links)

2) Between core networks as point-to-point trunk connections

3) In the access network, providing many users with access to core networks

(many low value links)• CAPANINA of eTOM• Enterprise Telecoms Operations Map

Aerial Platform Configurations and Spectrum Sharing (1)

Aerial Platform Configurations and Spectrum Sharing (2)

Work by exploiting the directionality of the user antenna

1) Simple Platform

2) Ships at different height – the wider the higher

47/48GHZ, 31/28GHZ ITU allotment

Optical Link Capacity

• Optical backhaul link• 10-12millimeter-wave backhaul• higher data rates using millimeter wave

band( 1.25Gb/s link )• Transfer non-time-critical data• Interplatform links cheaper than ground comm.

-450~650Km range

Broadband Trials To Fixed Users From Aerial Platform

•Different broadband services/applications•System testbed / equipment

System Testbed(1)

• 3 different aerial platform technologies

1)Tethered platform

2)Stratospheric balloon

3)Full HAP• Trial 1

1)BFWA up to fixed user using 28GHZband

2)end-to-end connectivity

3)High speed internet and video

4)Optical communication

System Testbed(2)

Trial 2 Balloon -> 28/29 GHZ Optical communication High data rate backhaul link Integration of multipayload system

Trial 3 2006

Wireless Equipment

Millimeter-wave trial equipment is based around 28/29 GHz and 28/31GHz frequency

Trial1 : tethered aerostat

- optical fiber, power

Trial2 : free flying stratospheric balloon- Strict weight- single beam coverage of footprint - millimeter wave link

Free-Space OpticalCommunications Equipment

Optical beam for optical interplatform link dependent

Atmosphere effect?

Intensity modulation with direct detection – short implementation time

Ground station tracking system

-> trial 1 : 270Mbps video signal

Delivery Broadband to High-Speed Vehicles

• CAPANINA project for High Speed Vehicles• Delivering broadband (backhaul) to trains

equipped with onboard WLAN access point

Selection of a Broadband Wireless Access Standard

HAPS :

1)seamlessly with existing communication network

2)Wide adoption among potential users

Good for Specific requirement, particular operating environment

IEEE 802.16SC – standard

Propagation Impairment

• ITU assigned millimeter wave band

1) Rain attenuation

2) Scattering

3) Relatively short, uncluttered link

4) Dropper effect

-> design of an efficient radio interface• HeliNet project Result

-> develop a suitable channel model including a short-term numerical model

-> implemented as a fast infrared filter with time-variant coefficients

The Radio Interface

Numerical channel extension for High-speed mobile application

Cutting edge technology

MIMO(multiple Input multiple output)

Advanced signal processing

Resource and Mobility Management

Good communication link under rapid movement.

-> Novel resource allocation strategies User - single HAP backhaul link develop: mobility,

interface solve efficient spectrum QOS

P. Pace, G. Aloi, F. De Rango, E. Natalizio, A. Molinaro, S. Marano

Dept. DEIS - University of CalabriaArcavacata di Rende (Cosenza) - Italy

{ppace, aloi, derango, enatalizio, molinaro, marano) @deis.unical.it

An intergrated Satellite_HAP-Terrestrial system architecture: resources allocation and traffic management issues

contents

1. Introduction

2. Benefits of HAP Communication

3. Satellite-HAP-Terrestrial system

4. Advantage of the scenario and open issues

4. Conclusion

1. Introduction

Terminology HMCS(HAP Master Control Station)

The terrestrial layer’s terminals within the same HAP coverage area have to use HAP transponder and HAP Master Control Station (HMCS) to send and receive data amongst themselves.

HGTW(HAP Gateway Station) the HAP Gateway stations (HGTW) guarantees communications

among users belonging to different HAP coverage areas using the CEO satellite links.

In order to guarantee an adequate quality of service to these kinds of service, it is required an efficient resources allocation and traffic management algorithm to be implemented inside the HMCS and HGTW stations.

Next generation satellite systems will provide personal communications to mobile and fixed users. As the demand grows for communication services, wireless solutions are becoming increasingly important. HAP

Platform : airplanes or airships , manned or unmanned

Position “wind”

HAPs can offer a wide range of services. Such services may particularly valuable where existing ground infrastructure is missing or difficult.valuable where existing ground infrastructure is missing or difficult.

HAPs are ideally suited to the provision of centralized adaptable resources allocation, i.e. flexible and responsive frequency reuse patterns and cell sizes, unconstrained by the physical location of base-stations, the smaller cells provide greater overall capacity as frequencies are reused a greater number of times within a given geographical area as shown in figure 2.

2. Benefits of HAP Communication

1. Large-area coverage

2. Flexibility to respond to traffic demand

3. Low cost

4. Incremental deployment

5. Rapid deployment

6. Platform and payload upgrading

7. Environmentally friendly

3. Satellite-HAP-Terrestrial system

The system architecture proposed in this work is shown in figure below

Usage User terminals cannot communication with each other without the

necessary use of HAPs forward and return links. HAP-Gateway (HGTW) terrestrial terminal must exists for each HAP

coverage area and guarantees communications among users belonging to different HAP coverage areas

HGTW links together HAP and satellite layers

HAP usage mitigates multipath effects, typical of terrestrial cellular systems, and decrease geostationary satellite propagation delays

This system scenario consists of tree layers

Terrestrial Layer user terminals, control and management stations Fixed Terminal (FT) and Mobile Terminal (MT)

HAP Layer The stratospheric platform layer hosts the set of HAPs. Since HAPs do not

have OBP, they act like simple hubs.

GEO Layer Satellite layer uses GEO regenerative satellites that are provided with On-

Board Processing (OBP). It can use forward channel both towards terrestrial layer and HAP layer.

IV. Advantage of the scenario and open issues

Advantage Simple design and implementation

An HAP layer can he seen as a terrestrial system extension.

– satellite does not have to manage traffic of a single terrestrial terminal user– terminals can be made without great financial and design efforts because

they do not have the task of interacting directly with the satellite segment.

Issue A channel assignment and resource allocation schemes will need to he

developed for the HAP scenario Integration with terrestrial and/or satellite architectures will also require

careful planning. Choice of an HAP and GEO layers protocol platform (MPEG, DVB, ATM, IP

…) Design of an efficient resources allocation and traffic management

algorithms. Design of traffic aggregation (integrated and differentiated) techniques Design of a centralized Call Admission Control (CAC) algorithm

the previous scenario adding the OBP capabilities over the HAPs

should be possible to share tasks at different layers and use less complex ground control station (HMCS, Satellite-MCS).

the users terminals should be hybrid terminals, able to work on different frequency bands and with very different power levels

these terminals will be more complex and expensive

laser communications can transmit data at rates up to 450 Mbps.

SILEX terminal could be used for a satellite HAPS link for high data rate communications.

V. Conclusion

This paper investigated the design of a integrated satellite-HAP-terrestrial architecture for telecommunications.

The haps layer give a added value to wireless communications because it offers reduced propagation delay and offer a broadband covertures.

2008.7.21

PEM

802.16e vs 802.20Wi-Fi Wi-MAX, MBWA, 3G

802.16 vs. 802.20 (1)

•IEEE, 2 working groups•Spec. for new mobile air interface for wireless broadband•Similar, but

•802.16 e : mobility in the 2 to 6 GHz•802.20 : operation in licensed below 3.5GHz

802.16 vs. 802.20 (2)

•802.16e from 802.16a(WiMAX Forum) standard

•802.16 uses existing Broadband Wireless Access(BWA)

• “inherent mobility of wireless media”

•Fills gap between Wireless MAN and WLAN

802.16 vs. 802.20 (3)

•802.20•Wireless MAN, real time data transmission rate•15Km cell range•Upto 250Km/h velocity

• cf)802.16 for (120-150Km/h)

802.16 vs. 802.20 (4)

•802.16e is looking at the mobile user walking around with PDA or laptop.•802.20 will address high-speed mobility issue.•Deployment in different method•1)16e : 16a cell footprint•2)20 : wider footprint deploy

802.16 vs. 802.20 (5)

• 802.20 will be a compete to 3G• “if 802.16e drives demand initially and

people are getting thirsty for it, a .20 solution could be deployed on a widespread basis and take advantage of users wants and demand for high-speed data.”

Bringing Wireless Access to the Automobile

Wireless Fidelity(Wi-Fi) : 802.11p-air interface between a wireless client and a base station

Worldwide interoperability of Microwave Access(WiMAX) : 802.16

- metropolitan area 에서 last mile problem 등 connection 에 대한 접근

Mobile Broadband Wireless Access(MBWA) : 802.20

- To enable worldwide deployment of affordable ubiquitous, interoperable multi-vender mobile BWA

Third-Generation (3G)

- Wireless network access for both stationary and moving

Comparison Parameters

• Performance

- Application dependent on (latency, low/high band)• Coverage Area

- Distance between Base station• Reliability

- Average number of dropped packet • Security

- encryption, authentication• Mobility

- Speed of mobile access point

Wi-Fi(802.11p)

• Mostly for mobility• First high-speed wireless• Limited range1)300 feet (for 802.11a)2)1000feet (for 802.11p)

WiMAX(802.16e)

•Standard for point-to-multi point wireless network•“last mile” connectivity•DSL like data rate•30 miles

MBWA (802.20)

•Mobile broadband, high-speed•155 mile/hour, for train•Wireless MAN, real-time transmission•Required channel bandwidth is small•9 mile of BS range•Handoff solution between 802.20 and 802.11-based LAN

3G

High-speed wireless communication

Cellular technology

Voice, data transmission for long-range wireless access

Performance

Coverage, mobility comparison

Reliability, Security Comparison

Conclusion

• Performance-latency, bandwidth

- WiMAX is the best. (100Mbps, 25-40ms)• Coverage area

- MBWA is the broadest• Reliability (???)

• Security (encryption, authentication)

- Wi-Fi, 3G• Mobility (speed)

- MBWA

Optical Free-Space Communications Downlinks from Stratospheric Platforms

Introduction(1)

STROPEX STRatospheric Optical Downlink Experiment

The CAPANINA Project Development of low-cost broadband service Providing efficient ubiquitous coverage Both mm-wave band and free space optic communication technology will

be used.

Free space optic communication Deliver very high data rates in clear air conditions Used for Interplatform links Supplement mm-wave band for backhaul traffic

Introduction(2)

Introduction(3)

Optical free-space point-to-point communication links Certain application involving HAPs

HAPs Location in a cloud free atmospheric altitude Enabling reliable line-of-sight links between different HAPs Meshed interconnected HAP network Optical down link to the terrestrial network would be feasible using site-

deversity

Introduction(4)

Technical benefits of optical free-space Low-weight Power impact High data rate Do not interfere with RF-transmmision

OIPL(Optical inter-platform-links)

1)Downlink experiment – test, evaluation

2)Two airships – further

Test Scenario(1)

Tethered Balloon Trial Autumn 2004, 400m altitude was tested Data rate was 270MBPS Transmission wave band was 808nm with 500mW mean source power Angle : 16 degree

Test Scenario(2)

Stratospheric Trials FELT (Free-Space Experimental Leaser Terminal) Ascending 2 hours to an altitude of 22Km, staying there 8 hours while it

drift of horizontally to max 60Km imposing a link distance of up to 64Km.

Test Scenario(3)

Atmospheric Attenuation and Index-of-Refraction Turbulence Atmospheric absorption and scattering along the link path Atmospheric attenuation can be kept below 2dB Molecular absorption lines of water vapour

IRT (Index-of-refraction turbulence) Caused by inhomogeneous distribution of the temperature Coherence of an optical field has dropped Imposing severe problems in terms of fading and heterodyning quality for

data receiver

Description of FELT(1)

FELT consists of motorised periscope for beam setting

Description of FELT(2)

Optical Layout Wavelength are 808nm as beacon from the optical ground station 9xx nm as beacon from the FELT 1550nm as carrier frequency for the IM/DD binary data stream 1550nm and 986nm ate combined 97x nm beacon source are also placed in the TX-path of the terminal

OGS-beacon is detected and tracked by the tracking sensor

Description of FELT(3)

PAT-processor

PAT(Pointing, Acquisition, and Tracking) Based on CMOS imaging sensor Video signal is processed by an Integrated vision system

Description of FELT(4)

Communication Sub-System 3 data source at different data rates(1.25Gbps, 270Mbps, 10Mbps) Available modulation onto the 1550nm data signal laser diode The different data rates shall enable the adoption to changing weather

situations with high atmospheric attenuation during the test flight

Ground Station and Channel Measurement devices

Ground Station Setup and Data Path Receiver system with 40cm aperture diameter is developed.

Channel Measurement Devices Character by statistical parameter Disturbances of intensity distribution (size and strength of variations of the

spackle patterns) Optical wave-front distortions MASS-profiler(Multi Aperture Scintillation Sensor) DIMM(Differential Image Motion Monitor)

Wavelength Selection and Terminal Architecture(4)