Robert J. Kerczewski and Rafael D. Apaza

Glenn Research Center, Cleveland, Ohio

Robert P. Dimond

Verizon Business, Cleveland, Ohio

AeroMACS System Characterization

and Demonstrations

NASA/TM—2013-216497

March 2013
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Robert J. Kerczewski and Rafael D. Apaza

Glenn Research Center, Cleveland, Ohio

Robert P. Dimond

Verizon Business, Cleveland, Ohio

AeroMACS System Characterization

and Demonstrations

NASA/TM—2013-216497

March 2013

National Aeronautics and

Space Administration

Glenn Research Center

Cleveland, Ohio 44135

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NASA/TM—2013-216497 1 

AeroMACS System Characterization and Demonstrations 

Robert J. Kerczewski and Rafael D. Apaza 

National Aeronautics and Space Administration 

Glenn Research Center 

Cleveland, Ohio 44135 

Robert P. Dimond 

Verizon Business 

Cleveland, Ohio 44135 

Abstract 

This The Aeronautical Mobile Airport Communications 

System (AeroMACS) is being developed to provide a new 

broadband wireless communications capability for safety 

critical communications in the airport surface domain, 

providing connectivity to aircraft and other ground vehicles as 

well as connections between other critical airport fixed assets. 

AeroMACS development has progressed from requirements 

definition through technology definition, prototype 

deployment and testing, and now into national and 

international standards development. The first prototype 

AeroMACS system has been deployed at the Cleveland 

Hopkins International Airport (CLE) and the adjacent NASA 

Glenn Research Center (GRC). During the past 3 years, 

extensive technical testing has taken place to characterize the 

performance of the AeroMACS prototype and provide 

technical support for the standards development process. The 

testing has characterized AeroMACS link and network 

performance over a variety of conditions for both fixed and 

mobile data transmission and has included basic system 

performance testing and fixed and mobile applications testing. 

This paper provides a summary of the AeroMACS 

performance testing and the status of standardization activities 

that the testing supports. 

1.0 Introduction 

Wireless communications for airport surface safety critical 

aviation applications has been considered since the late 1990s. 

The German Aerospace Center (DLR) researched the 

application of multicarrier code division multiple access to 

enable an Advanced Airport Data Link (ADL) to fulfill the 

communications requirements of the Advanced Surface 

Movement Guidance and Control System (Ref. 1). ADL 

aimed to provide data communications between air traffic 

controllers, airport authorities, and airline companies and 

aircraft on the airport surface. The possible use of 5000 to 

5150 MHz band for the ADL system was considered at that time. 

In the early 2000s, the Federal Aviation Administration 

(FAA) in conjunction with MITRE-CAASD began developing 

the Airport Network and Location Equipment (ANLE) 

concept. In (Ref. 2), ANLE is described as a “high integrity, 

“safety rated” wireless local area network (LAN) for the 

airport area, combined with a connected grid of multilateration 

sensors. The former would provide the cockpit with access to 

appropriate information via a high-bandwidth internet-like 

connection. The latter would use those same transmissions to 

derive three-dimensional position of the terminal—position 

that could then be broadcast via the same data link to provide 

all users with situational awareness on the airport surface. 

Adding simple transmitters to other surface-movement 

vehicles would allow for the development of a high-fidelity 

complete picture of the airport surface environment.” ANLE 

was proposed for the under-utilized 5091 to 5150 MHz band, 

which was allocated to the aeronautical radionavigation 

service (ARNS) for implementation of Microwave Landing 

System (MLS), but for which no MLS channels had yet been 

assigned. The 5091 to 5150 MHz band, also referred to as the 

MLS Extension Band, also contains an allocation to fixedsatellite service (FSS) for use by non-geostationary (nonGSO) mobile-satellite service (MSS) feeder uplinks. MITRECAASD performed initial analyses of the sharing of the MLS 

Extension Band between the MSS feeder links and the ANLE 

system as reported in Reference 3, to validate the feasibility of 

sharing this band between the two systems. This supported the 

addition of an aeronautical mobile (route) service (AM(R)S) 

allocation to the MLS Extension Band that could support the 

ANLE system at the World Radiocommunication Conference 

(WRC) 2007. Analysis of the compatibility between the 

airport surface wireless network and MSS feeder links has 

continued in order to establish the AeroMACS power 

transmission limits which will ensure, including work by both 

MITRE-CAASD and NASA Glenn Research Center (Refs. 4 

and 5). 

In 2002, the NASA Glenn Research Center considered 

possible communications, navigation and surveillance 

requirements for the airport surface in formulating a new 

research project eventually called Space-Based Technologies 

(SBT). At the Second Integrated Communications, Navigation 

and Surveillance (ICNS) Conference in April 2002, the 

recommendation was made to identify and address research 

efforts where current work is inadequate or underfunded 

regarding integration of multiple applications on the ground, 

the CNS performance requirements of integrated applications, 

and the data networking implications of this integration 

(Ref. 6). As a result, the SBT Project included a major effort 

in airport surface communications. 
NASA/TM—2013-216497 2 

The SBT Project studied communications requirements on 

the airport surface and potential system architectures through inhouse and contracted efforts. The results of these studies 

(Refs. 7 and 8) helped establish the basis for what became the 

AeroMACS system. Further studies by MITRE-CAASD 

(Ref. 9) built upon the SBT Project requirements studies and 

other analyses enabled the estimate of spectrum requirements 

supporting the MLS Extension Band AM(R)S spectrum 

allocation approved at WRC 2007. 

By 2007, the FAA and Eurocontrol had completed a joint 

study called the Future Communications Study, investigating 

the future communications requirements for aviation. Among 

many outputs, this study concluded that the IEEE 802.16e 

standard was the preferred technology for an airport surface 

wireless communications network, thereby establishing an 

international consensus that enabled AeroMACS standardization to proceed. 

Under the SBT Project, NASA Glenn Research Center 

entered into a cooperative agreement with Sensis Corporation 

which resulted in the establishment of what eventually came to 

be known as the NASA-CLE CNS testbed, located at the NASA 

Glenn Research Center (GRC) and adjacent Cleveland Hopkins 

international Airport (CLE). In this testbed, the feasibility of 

using wireless communications networks for integration of 

surface surveillance was established by interconnecting several 

Airport Surface Detection Equipment (ASDE-X) sensor units 

and transmitting sensor data to a central processing station 

(Ref. 10). Prior to the availability of IEEE 802.16e equipment, 

the surface wireless network was implemented using 802.11 

equipment operating in the MLS Extension Band. 

The SBT Project also developed a measurement campaign to 

characterize the MLS Extension Band propagation channel in 

the airport environment. Under a cooperative agreement with 

Ohio University, channel propagation measurements were made 

at several large, medium and small airports in the United States 

(Ref. 11). The test results enabled the development of path loss 

and airport channel models valid for the 5091 to 5150 MHz 

band that enabled the development of detailed simulations of 

802.16e performance for the airport surface application. 

In 2009, under a cooperative agreement with ITT-Exelis and 

with funding provided by the FAA, the first AeroMACS 

prototype was established within the NASA-CLE CNS Testbed. 

With the availability of 802.16e equipment, including base 

stations and subscriber units, tuned to the MLS Extension band 

now allocated for the AeroMACS service, testing was initiated 

to provide technical results upon which national and 

international standards for AeroMACS could be established. A 

description of the AeroMACS system development can be 

found in Reference 12. 

During the past 3 years, extensive technical testing has 

taken place to characterize the performance of the AeroMACS 

prototype and provide technical support for the standards 

development process. This testing has characterized 

AeroMACS link and network performance over a variety of 

conditions for both fixed and mobile data transmission. 

During 2012, the first two practical AeroMACS 

demonstrations have taken place, demonstrating both the fixed 

and mobile aspects of AeroMACS. The first demonstration 

utilized a Boeing corporation 737 jet equipped with an 

AeroMACS antenna and subscriber station, enabling the 

evaluation of the AeroMACS performance in bringing safety 

critical flight information to the cockpit. This event marked 

the first use of an aircraft involved in AeroMACS testing, 

augmenting previous mobile testing which utilized a ground 

vehicle offering speeds and reception characteristics which 

differ greatly from the commercial aircraft. 

The second demonstration involved the suitability of 

AeroMACS to transmit live safety critical data between fixed 

assets. Live radar data from an Airport Surveillance Radar 

model 9 (ASR-9) was transmitted from the ASR-9 site to the 

air traffic control tower at CLE. This was the first 

demonstration of broadband transmission of live safety critical 

data over AeroMACS, and has established the potential for 

AeroMACS to be applied to many airport fixed asset 

communications requirements. 

In the following sections, the AeroMACS prototype as 

instantiated in the NASA-CLE CNS Testbed is described, 

followed by a summary of AeroMACS performance testing. 

The focus of the paper will be on describing the most recent 

AeroMACS testing results, including the Boeing 737 aircraft 

mobility testing and the fixed safety critical data transmission 

testing. The status of AeroMACS standardization activities 

will also be provided. 

2.0 AeroMACS Testbed Description 

One of the primary goals of the NASA-CLE CNS Testbed 

as initially established was to enable testing of the 

interconnection of ASDE-X sensors via an airport surface 

wireless communications network (Ref. 13). The testbed 

included assets at three different airports, including CLE, 

Cleveland Burke Lakefront Airport, and Lorain County 

Regional Airport to allow testing of wide area multilateration, 

remotely staffed virtual air traffic control, assessment of 4D 

arrival and departure trajectories, and advanced integrated 

surveillance. The installation of an ASDE-X system for testing 

required the placement of eight multilateration sensors at CLE 

in order to achieve full airport surface coverage. The use of an 

initial IEEE 802.11 wireless network enabled the fixed ASDEX sensors to be interconnected to the ASDE-X processor, 

allowing real-time airport surface surveillance to be established. 
NASA/TM—2013-216497 3 

Figure 1.—AeroMACS prototype testbed. 

Figure 1 shows a diagram of the current AeroMACS 

prototype testbed. Before the ASDE-X tests were completed, 

the prototype AeroMACS system was installed. This system 

consisted of two base stations and fixed and mobile subscriber 

stations. The fixed subscriber stations (denoted by “SS” in 

Fig. 1) were placed coincident with the ASDE-X sensors, 

allowing a final set of tests with the ASDE-X system using the 

AeroMACS prototype instead of the 802.11 network. These 

tests proved that AeroMACS provided equivalent performance 

in support of the ASDE-X system. After these tests the 

ASDE-X test system was removed, but the AeroMACS 

subscriber units remained at the same locations. 

The location of the two base stations (BS-1 and BS-2 in 

Fig. 1) covers the majority of the airport surface of CLE. The 

base stations communicate with subscriber stations that are 

within their coverage. They also communicate with each other 

through a microwave backhaul link. This arrangement enables 

testing of handoffs between base stations that is required for 

mobile AeroMACS connectivity as well as for handling cases of 

temporary obstructions of fixed subscriber stations. 

The AeroMACS testbed also includes a mobile element, 

called the Aeronautical Research Vehicle (ARV) as shown in 

Figure 2. The ARC consists of a ground vehicle fully equipped 

with a subscriber stations, test and measurement systems, and 

video camera. The ARV enables testing of many mobile 

aspects of AeroMACS without the cost and difficulty of using 

aircraft. However the ARV is limited in terms of size, speed 

and access compared to an actual aircraft, hence the testing 

described below was essential in demonstrating AeroMACS 

performance for real aeronautical mobile applications. 

Figure 2.—Aeronautical Research Vehicle (ARV) for 

AeroMACS testing. 

3.0 AeroMACS Prototype Testing 

The primary AeroMACS prototype testing took place 

during 2010 and 2011 (Refs. 14 and 15). With the 

configuration described in the previous section, static testing 

of the AeroMACS network using the fixed subscriber stations 

has been ongoing since the establishment of AeroMACS 

equipment in 2009. However the mobility requirement for 

AeroMACS is the critical and most difficult one, hence the 

ARV was used extensively for these tests. The ARV often 

operated around the perimeter of CLE so as not to interfere 

with airport operations. Some critical testing also took place 

on the airport taxiways and runways when no aircraft 

operations were taking place. These various areas allowed 
NASA/TM—2013-216497 4 

both line-of-sight (LOS) and non-line-of-sight (NLOS) 

between the base stations and the mobile subscriber station. 

The AeroMACS testing consisted of AeroMACS mobility 

testing; testing of Multiple antenna configurations (multipleinput/multiple output, or MIMO) on the vehicle; and testing of 

vehicle speed effects. 

For all of this testing, the AeroMACS prototype network 

parameters are as described in Tables 1, 2, and 3. 

Testing was performed for three mobile subscriber station 

antenna configurations: single antenna; two antennas 

separated by one wavelength; and two antennas separated by 

10 wavelengths. 

Base station transmit power was set to 25, 50 or 100 mW. 

The vehicle speed was set to 13, 26 or 40 kn. 

In general the AeroMACS mobility testing showed robust 

performance, producing throughput rates ranging from 

approximately 0.5 to 4.5 Mbps, depending primarily on the 

distance of the vehicle from the base station as well as 

LOS/NLOS condition. This performance was seen in the 

several airport surface test regions: Runways (low multipath, 

high speed); Terminal areas (High multipath and LOS/ 

NLOS)); and Service road (Long range, variable multipath, 

LOS/NLOS).

TABLE 1.—BASE STATION PARAMETERS 

Transmit power 21 dBm maximum 

Channel bandwidth 5 MHz 

Maximum antenna gain 15 dBi 

Antenna beamwidth 90° azimuth by 8° elevation 

Antenna mode 22 MIMO (2Rx, 2Tx) 

Matrix A, MRC 

Maximum transmission unit 1440 bytes 

Downlink/Uplink ratio 60/40 

Hybrid automatic repeat request 

(HARQ) 

Enabled 

AAA server Enabled 

PKMv2, EAP-TTLS security Enabled 

AES-128 air link encryption Enabled 

TABLE 2.—MOBILE SUBSCRIBER STATION PARAMETERS 

Transmit power Adaptable: 21 dBm 

maximum 

Maximum antenna gain 8 dBi 

Antenna beamwidth Omindirectional on 

horizon 

Antenna mode 22 MIMO (2Rx, 1Tx) 

TABLE 3.—COMMON BASE STATION AND SUBSCRIBER 

STATION PARAMETERS 

Modulation Adaptive: 

QPSK, QAM-16, QAM-64 

Forward error correction Adaptive: 

CTC 1/2, 2/3, 3/4, 5/6 

Figure 3.—Average throughput rate for the service road drive 

test. 

The MIMO testing validated the use of use of MIMO for the 

subscriber station receive antenna as it showed improved 

receiver performance and lower base station transmit power 

requirements, enabling deployment of additional airport 

installations while still remaining below the mobile satellite 

service feeder link interference threshold. 

Figure 3 shows the results of the service road test. The 

MIMO configuration outperformed the single antenna case, 

and the two antenna 10 wavelength spacing outperformed the 

one wavelength spacing. The one wavelength antenna spacing 

(2.3 in., 5.9 cm) performed the same as the single antenna case 

with reduced base station transmit power, verifying that the 

MIMO installation enables a reduction of base station transmit 

power and potentially more airport installations. 

The measured data throughput as a function of vehicle 

velocity showed negligible difference up to 40 kt velocity. 

Additional velocity test results are presented in the next 

section. 

4.0 Mobile Application Testing 

The first mobile applications testing of AeroMACS was 

performed using a Boeing 737-700 that was provided by Boeing 

from their corporate fleet. These activities constituted the first 

use of AeroMACS using an actual aircraft, including use of an 

antenna designed for aircraft use (Refs. 14 and 16). The aircraft 

tests also differed from the ARV testing by offering 

significantly greater antenna height placement and vehicle 

velocities. The activities demonstrated the first two-way 

AeroMACS data link service providing flight critical data. 

The aircraft was fitted with a Sensor Systems S65-5366-720 

5 GHz antenna, temporarily replacing the standard VHF blade 

antenna as shown in Figure 4. The ARV’s subscriber unit, a 

prototype AeroMACS unit with external antenna leads was 

installed in the aircraft and connected to the 5 GHz antenna. 

United Airlines provided hangar facilities for making the 

necessary onboard modifications. 
NASA/TM—2013-216497 5 

Figure 4.—Boeing 737-700 aircraft used for AeroMACS 

mobility testing showing location of AeroMACS antenna. 

The AeroMACS subscriber station onboard the Boeing 737-

700 was configured to associate with base station sector 2-3 of 

the base station located at the ARFF facility on the eastern 

side of CLE (Fig. 1). The sector offers 60 of LOS coverage to 

the north and south of the sectors 270 heading. 

Two activities were performed using this configuration. The 

first activity consisted of characterizing the performance of 

AeroMACS onboard a Boeing 737-700 by repeating a subset 

of the drive test scenarios previously conducted with the ARV 

for the AeroMACS baseline tests described in the previous 

section. Tests were performed using similar airport surface 

and runway routes at velocities up to 80 kt. The second 

activity further validated the performance of AeroMACS by 

demonstrating the successful use of safety critical aeronautical 

mobile applications using AeroMACS as the application data 

link. For both activities, the aircraft remained on the ground in 

taxi mode in the gate, terminal and taxi areas and on Runway 

24 L (Fig. 1) as are appropriate for an aircraft using 

AeroMACS. 

The Boeing 737-700 performance characterization resulted 

in the collection of AeroMACS performance data enabling a 

comparison with the baseline ARV test data. This comparison 

revealed that the Boeing 737-700 installed AeroMACS system 

had performance characteristics similar to the results obtained 

during the ARC testing. Of interest are the aircraft taxi tests as 

a function of velocity. A small throughput performance 

dependency with vehicle velocity was measured as aircraft 

speeds increased above 40 kt. Table 4 shows the average 

throughput as a function of velocity. Figure 5 shows the 

effects of vehicle velocity as the aircraft travelled down 

Runway 24 L. The effects of proximity to the base station are 

visible in this figure as well, with the base station location 

approximately one-third of the distance from the northeast end 

of Runway 24 L (Fig. 1). These test results indicate that 

AeroMACS can achieve good performance up to 50 kt as 

required by AeroMACS Profile (Section 6.0).

TABLE 4.—AVERAGE THROUGHPUT AS A FUNCTION OF 

VEHICLE SPEED 

Speed, 

kt 

Vehicle Average throughput, 

Mbps 

40 ARV 4.7 

40 Boeing 737 4.8 

60 Boeing 737 4.2 

80 Boeing 737 3.9 

Figure 5.—Effects of vehicle velocity on throughput from 

runway 24 L taxi tests. 

The AeroMACS validation activity required a suitable air 

traffic control or air traffic services application over 

AeroMACS to the Boeing 737-700 as it taxied across the 

airport surface. This effectively demonstrated the performance 

and feasibility of AeroMACS for safety critical mobility 

applications. The selection of an appropriate application was 

influenced by operational continuity considerations, including 

FAA plans to implement early data communications 

capabilities over VDL Mode 2 as part of the FAA’s 

DataComm Program. Other considerations included the 

maturity of the data link service definition, the service 

availability (whether or not the service currently exists or can 

be suitably emulated), and hardware and software integration 

considerations. 

The application chosen to validate the AeroMACS 

technology was a navAero T-1000 Electronic Flight Bag 

(EFB) system hosting a weather applications from WSI 

Corporation known as InFlight, capable of presenting cockpit 

staff with critical en-route meteorological data such as 

Airmen’s Meteorological Information (AIRMETs), Significant 

Meteorological Information (SIGMETs), and terminal 

conditions through Meteorological Aerodrome Reports 

(METARS). Figure 6 illustrates WSI’s EFB showing a 

regional radar graphic with textual METARs inset for CLE. 

The Inflight system typically consists of a stand-alone 

SIRIUS satellite radio receiver which utilizes a 100BaseT 

Ethernet connection to interface the unit to an EFB or 

multifunction display (MFD). The system is normally meant 

 
NASA/TM—2013-216497 6 

Figure 6.—A sample weather screen showing radar (with 

impending rain) and a current METAR for CLE. 

to be used onboard an individual aircraft, however the 

intended demonstration consisted of interfacing the satellite 

receiver unit into the AeroMACS testbed and utilizing the 

wireless data link to provide “last mile” services to the 

cockpit. Due to a satellite receiver failure, the configuration 

was further altered to utilize AeroMACS to connect to WSI 

demonstration system connected to the internet. 

WSI’s InFlight EFB weather application caches the 

packetized information broadcast over the Sirius satellite 

system. For timely information, the entire system, from 

receiver to EFB, should be on receiving broadcast updates. 

With SIRIUS data rates confined to 64 kbps and below, the 

4 Mbps average throughput of the AeroMACS system’s 

wireless data link component to aircraft, or even the 

1.44 Mbps interface to the Internet, had no negative impact 

upon the demonstration application. 

5.0 Safety Critical Fixed Asset Testing 

The opportunity to test AeroMACS using an actual critical 

fixed application was presented when Cleveland FAA initiated 

plans for the construction of a new Air Traffic Control Tower 

(ATCT) facility. The optimal location for construction of the 

new ATCT facility was determined to be in close proximity to 

the ASR-9 system. As a consequence of the new ATCT 

construction location, the existing radar sensor was scheduled 

for displacement to a location north of the airport. To enable 

seamless air traffic operations, the FAA operates an existing 

surveillance facility until a new radar system is built, 

optimized and thoroughly tested. The scheduled change of 

surveillance systems at Cleveland airport gave rise to the 

opportunity for testing AeroMACS utilizing the radar system 

scheduled for removal. With the approval and cooperation 

from FAA CLE Radar System Support Center (SSC), a plan 

was formulated to integrate AeroMACS into the 

communications infrastructure at Cleveland airport, interface 

it with the surveillance system and subsystems and conduct 

testing.

In preparation for testing in a relevant environment, 

communications equipment was obtained to conduct initial 

equipment setup and testing at a NASA GRC laboratory. 

Laboratory equipment configuration and layout was designed 

to replicate surveillance communications requirements at 

ASR-9 radar facilities. Laboratory equipment consisted of 

AeroMACS subscriber stations, Codex 3600 modems, 

Newbridge 3624 Channel bank systems and media converter 

equipment. The scope of the laboratory test was to configure 

modems and channel bank systems to transport information at 

the correct data rates while adhering to communication 

protocols in use. AeroMACS uses Transmission Control 

Protocol/Internet Protocol (TCP/IP) for communications 

exchange. The communications interface in use by 

telecommunications equipment commonly use T1 or DS-0 

levels (1.544 Mbps). To enable the exchange of information 

between the T1 channel bank system interface and IP interface 

provided by AeroMACS, a media converter system was used. 

The media converter unit was able to packetize T1 channels 

and provide timing signals for end-to-end channel bank 

operation. In laboratory testing, the AeroMACS system was 

able to transport 24 channels of a T1 system. Error free endto-end bit error rate tests were conducted and the laboratory 

system configuration was successfully tested under different 

data rate load configurations and with different modem 

parameters. 

Starting in April of 2012, NASA and FAA personnel 

proceeded to install AeroMACS equipment at the ASR-9 

surveillance facility and ATCT. The AeroMACS subscriber 

station was deployed at the radar tower structure and the 

Power Over Ethernet (POE) system and Newbridge Channel 

Bank were installed in the radar building. The POE and 

AeroMACS SS were connected using Ethernet cabling. At the 

ATCT, an AeroMACS subscriber station was installed on top 

of the Mezzanine building and cabled to the FAA equipment 

room where the Newbridge Channel Bank and POE where 

deployed. The wireless configuration utilized the base station 

to connect the subscriber station deployed at the ATCT and 

subscriber station deployed at ASR facility as shown in 

Figure 7. Although an actual National Airspace System 

deployment will not utilize a two-hop configuration, the 

NASA test bed AeroMACS prototype system did not offer a 

single hop architecture option. Bit error rate tests were 

conducted employing loading and configurations used in the 

earlier laboratory tests, showing zero bit errors generated 

during the data transmission. 

The new surveillance system in Cleveland was 

commissioned in July 2012, thus freeing up the old radar 

system for AeroMACS testing. At the ASR-9 location, the 

AeroMACS subscriber station was interfaced to the ASR-9 

Racal modem systems through the existing Data Probe 

switching system. At the ATCT the AeroMACS subscriber 

station was interfaced to the corresponding modem systems as 

shown in Figure 8. To monitor the performance of the 

communications system, a radar analysis tool (WRTADS) was 

used to display and record system performance. The analysis 
NASA/TM—2013-216497 7 

Figure 7.—Wireless configuration for ASR-9 safety critical fixed asset tests. 

Figure 8.—AeroMACS-ATCT-ASR-9 interfaces. 
NASA/TM—2013-216497 8 

Figure 9.—AeroMACS-ASR-9 test voice grade line performance. 

tool was deployed at both the ASR-9 and ATCT locations. At 

the ASR-9 location, the radar analysis tool was connected to 

the Communications Radar Interface Box where tracks 

produced by the radar system could be recorded for post 

processing. At the ATCT, the radar analysis tool was 

connected to the Serial Communications Interface Panel where 

received radar tracks were recorded for post processing and 

comparison with recordings at the sensor location. The testing 

indicated that the AeroMACS system was successfully able to 

transport critical radar information from the radar source to the 

ATCT. Figure 9 illustrates the performance of the voice grade 

line performance. The loss performance from 400 to 3000 Hz 

is negligible and illustrates the signal quality being provided to 

the modem system. 

Future AeroMACS evaluations will include testing of 

system performance utilizing a single hop wireless 

configuration. This configuration would enable the evaluation 

of system latency under high communications demand loading 

using shared services configuration. The fixed asset testing 

successfully demonstrated that AeroMACS is able to meet the 

requirements for transporting critical surveillance data in a 

reliable and efficient way. 

6.0 AeroMACS Standards Development 

Worldwide interoperability is a critical element in the design 

of AeroMACS technology. AeroMACS will be required to 

provide seamless worldwide communications services while 

meeting the needs of many different users. Collaborative efforts 

to standardize AeroMACS are concurrently taking place in the 

United States and Europe. In the United States Radio Technical 

Commission for Aeronautics (RTCA) Special Committee (SC) 

223 is working in the development of Minimum Operational 

Performance Standards (MOPS) and the WiMAX Forum has 

established a working group to address aviation interests. In 

Europe standardization efforts are being accomplished through 

EUROCAE Working Group (WG)-82 in developing MOPS 

and MASPS. The International Civil Aviation Organization 

(ICAO) is working in the development of Standards and 

Recommended Practices (SARPS) and Concept of Operations 

(ConOps). Common AeroMACS standards development in the 

U.S. and Europe has been requested by ICAO in response to 

the ANC-11 recommendation for global interoperability and to 

help expedite ICAO approval of international AeroMACS 

standards. The following sections provide information on 

ongoing standardization efforts by these organizations. 

6.1 RTCA Standards Development 

RTCA is an organization that through consensus develops 

Communications, Navigation, Surveillance (CNS) and Air 

Traffic Management (ATM) recommended standards for the 

United States Aviation. In 2009 a technology standardization 

effort for AeroMACS to support future mobile and fixed data 

communication applications and services for both ground/air 

and ground/ground communications services on the airport 

surface was proposed to RTCA’s Project Management 

Committee (PMC). On the seventh of August 2009, RTCA 

PMC approved the Terms of Reference (TOR) document to 

proceed with AeroMACS standards development. The TOR 

document specified the delivery of the following products: 

Aviation System Profiles for Airport Mobile Access 

Communications Network and MOPS for Airport Surface 

Wireless Mobile Access Communications Network. 
NASA/TM—2013-216497 9 

6.2 RTCA SC-223 

The RTCA Special Committee on Airport Surface Wireless 

Communications, SC-223, was established in August 2009 to 

develop the AeroMACS profile and MOPS. With support from 

industry, government, EUROCONTROL and WG-82 the U.S. 

final draft profile was completed at the end of 2010. The 

AeroMACS profile is a joint RTCA and EUROCAE 

development effort based on the WIMAX document, WiMAX 

Release 1 System Profile. This airport wireless communications 

technology has been developed based on a specific WiMAX 

Forum profile of the IEEE 802.16-2009 standard. Use of an 

established IEEE standard enables the aviation community to 

leverage extensive international standards collaboration and 

commercially provided components and services. The profile 

document specifies the use of selected 802.16-2009 technical 

parameters that best serve the aviation needs. Parameters have 

been selected to meet mobile station requirements considering 

different users, varied environments and operational uses. The 

AeroMACS profile closely follows the format of profiles 

developed by the WiMAX Forum for commercial and industrial 

use and is expected to be incorporated as one of several 

WiMAX Forum Certified profiles. Airborne MOPS 

development started in 2011 and is scheduled to conclude in late 

2012. MOPS objectives are to develop standards for both 

Airborne Component and Ground Based base station 

components of AeroMACS. 

6.3 WiMAX Forum 

The WiMAX Forum is an industry-led, not-for-profit 

organization that certifies and promotes the compatibility and 

interoperability of broadband wireless products based upon 

IEEE Standard 802.16. The WiMAX Forum has created the 

Aviation Working Group. The Working Group acts as a focal 

point for Worldwide Aviation Industry interest in WIMAX as a 

technology for Aviation Applications, and promotes WiMAX as 

the premiere technology for Aviation Applications on a global 

basis. In August of 2010, an ad-hoc joint committee was formed 

between RTCA SC-223 and the WiMAX Forum to facilitate 

development of an AeroMACS profile. 

6.4 EUROCAE Working Group 82 (WG-82) 

The European Commission and EUROCONTROL have 

sponsored work projects under SESAR (Single European Sky 

ATM Research) Joint Undertaking (SJU) to progress the 

design and assessment of all future air/ground data link. 

EUROCAE assigned WG-82 to develop airport surface 

wireless communication standards in Europe. The group 

started in January 2010 with the purpose to develop the 

appropriate standards relative to new air-ground data link 

technologies including those associated with airport surface, 

and enroute/TMA using terrestrial and satellite 

communications (1). The working group is tasked with 

delivering a total of four documents. The AeroMACS Profile 

and Airborne equipment MOPS documents are jointly 

developed by RTCA and EUROCAE and the System level 

MASPS and Ground Equipment MOPS documents are 

developed only by EUROCAE. European WG-82 

standardization support includes participation from 

EUROCONTROL, ANSPs (AENA, DSNA, DFS), Industry 

(INDRA, SELEXELSAG, THALES, SAAB, COBHAM, 

HITACHI) and Industry Forums (WMF). WG-82 is scheduled 

to deliver its document at the end of 2013. 

6.5 ICAO SARPS 

ICAO is a special agency of the United Nations responsible 

for the adoption of standards and recommended practices 

concerning air navigation. The development of Aviation 

Standards and Recommended Practices is done under the 

direction of the Air Navigation Commission (ANC) through 

the formal process of ICAO working group panels. The ANC 

is the ICAO technical body. In March of 2012 the first 

Aeronautical Communications Panel (ACP) Working Group S 

meeting convened in Montreal, Canada to commence 

standardization of airport Wireless Communications. The 

Terms of Reference document for Working Group S defines 

the following objectives for the group: 

 Develop ICAO SARPs and Technical Manuals for 

AeroMACS. 

 Define and describe AeroMACS security framework for 

worldwide interoperability. 

 AeroMACS addressing and discovery mechanism that is 

consistent with ATN/IPS for global interoperability 

while permits local implementation flexibility. 

 Coordination with international technical 

standardization bodies. 

 Provide input to development of frequency planning 

criteria. 

At the writing of this paper the development of SARP 

document outline is completed and work to define the standard 

is progressing with support from different states and industry. 

Additionally, a Concept of Use document is being developed 

to serve guide the development of requirements. 

7.0 Summary 

The need for an integrated wireless communications network 

capability for the airport surface has been recognized since the 

1990s, and several research and study efforts have advanced the 

concept. Requirements analyses provided the airport surface 

communications spectrum requirements, and interference and 

spectrum sharing studies proved the feasibility of adding an 

AM(R)S allocation to the 5091 to 5150 MHz MLS Extension 

Band to accommodate the airport surface wireless 

communications system, which was accomplished at WRC 

2007. The FAA-Eurocontrol Future Communications Study 
NASA/TM—2013-216497 10 

verified that the IEEE 802.16e standard is appropriate for the 

AeroMACS system. As this standard supports the well-known 

WIMAX implementation, an aviation profile based on WIMAX 

has been developed by RTCA and EUROCAE, and the name 

AeroMACS has been accepted to refer to the emerging airport 

wireless communications network. Channel propagation 

measurements have been performed at several airports, 

providing data for the development of channel models used for 

simulations of the AeroMACS profile. The availability in 2009 

of IEEE 802.16e equipment tuned to the MLS Extension Band 

enabled the deployment of the first AeroMACS prototype as 

part of the NASA-CLE CNS Testbed located at the NASA 

Glenn Research Center and adjacent Cleveland Hopkins 

International Airport. 

This paper has focused on the results of testing of the 

AeroMACS prototype from 2009 through 2012 at the NASACLE CNS Testbed, and has also provided the status of the 

AeroMACS standardization process. Testing of the mobile 

aspect of AeroMACS was performed first using a ground 

vehicle equipped with an AeroMACS mobile subscriber 

station. A second series of tests used a Boeing 737-700 

equipped with an AeroMACS mobile subscriber station and a 

C-Band aircraft antenna to repeat some of the ground vehicle 

tests and also to demonstrate transmission of a real weather 

application representative of safety critical service application. 

A third set of tests demonstrated the transmission of high rate 

safety critical radar data over AeroMACS. From these results, 

it can be concluded that the performance of AeroMACS in 

supporting safety critical aviation communications for both 

fixed and mobile applications will be sufficient to enable the 

deployment of AeroMACS. The standards required to support 

future deployments and ensure international compatibility are 

advancing toward completion. Although AeroMACS testing 

and demonstration will continue while standards are finalized, 

AeroMACS is poised for operational deployment in the near 

future. 

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