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DRM Overview: The Technology and the Transition Path

To the Digital Future of AM Radio

Harris Corporation

Introduction: Every new technology brings with it a combination of anticipation and

dread: anticipation because no matter what the new technology is, its entire reason for

being is that it promises new capabilities or overcomes some limitations, and dread

because some degree of change will be required to realize the benefits.

Digital Radio Mondiale (better known as DRM), one of the most significant

breakthroughs in radio since the inception of broadcasting, is no exception. As the next

generation of AM radio, this digital, in-band system will give broadcasters and listeners

capabilities that were unimaginable in an analog world. But to experience these

capabilities, changes will be required. Broadcasters will need to upgrade their

transmission facilities and even more importantly, listeners will need to upgrade their

receivers—no small concern since the widespread availability and distribution of low-

cost receivers has been one of the most important reasons why AM has long been the

world’s most popular form of mass communication by far.

This paper will take a close look at DRM, examining three key areas:

First, the background, the technology and the anticipated global adoption of DRM;

second, what will be required to upgrade a transmitter in general and a Harris DX

transmitter in particular for DRM, and third, an overview of Harris’ DRM product

platform—a platform designed to make the migration from analog to digital broadcasting

as smooth and as cost-effective as possible.

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I. The Background, the Technology and the Anticipated Adoption of DRM

DRM became a reality on June 16, 2003. On that day in conjunction with the

ITU’s World Radiocommunication Conference in Geneva, Switzerland, 13 broadcasters

from across the globe simultaneously initiated live, daily DRM broadcasts. As these first

regular broadcasts—and also a number of special demonstration broadcasts--hit the air,

there was no question that an impressive amount of work had been accomplished to take

DRM from the minds of a small group of broadcasters and manufacturers who met for

the first time in 1998 to an effective working system today.

But what motivated the development of a new radio standard when AM radio—

including the short wave, medium wave and long wave broadcast bands under 30 MHz—

was already so popular? What technologies were involved? And how was DRM

expected to be adopted worldwide? Let’s take a look at each of these questions:

The Development and Benefits of DRM

The formal development of DRM began on March 5, 1998 when 20 of the

world’s most important broadcast-related organizations met in Guangzhou, China with

one goal in mind—to revitalize AM broadcasting by facilitating the spread of AM digital

technology around the world.

As they signed the Digital AM Memorandum of Understanding during the

meeting in Guangzhou, these organizations put the development of DRM on a formal

footing and took the first step toward its official inauguration.

From the beginning, DRM’s proponents were committed to formulating a digital

AM system design that could serve as a single, tested, non-proprietary and evolutionary

world standard that would be market-driven and consumer-oriented. Conceptually, the

new system was expected to deliver high quality mono sound with the advantages and the

coverage of AM, using the same frequency assignments, supporting the same listening

conditions (fixed, portable and mobile), and covering all listening environments (indoors,

densely-populated cities with high electrical noise, sky wave and ground wave

transmission paths, interference, etc.).

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It was a given that resulting DRM receivers would need to be low-cost, consume

little energy, and be easy to tune with selection by frequency, station name, or program

type.

However, while maintaining the best qualities of analog AM, the benefits of the

new system would go far beyond improved sound quality. As a digital system, DRM

would give listeners a more versatile receiver with ease of station selection, and new data

services, both program associated (e.g., text information, station name, song title,

performer’s name) and program independent (e.g., weather updates, other data services).

DRM would offer many benefits to broadcasters as well. In addition to

preserving the AM channel infrastructure (or even making it more efficient), DRM would

enable some broadcasters with modern transmission systems to transition from analog to

digital service with a relatively simple and cost-effective equipment upgrade in the field.

Bringing Together Field-Proven Technologies

DRM has managed to achieve all of these benefits and practicalities by combining

a number of the most advanced signal generation and reception technologies, including:

• AAC (Advanced Audio Coding)

• SBR (Spectral Band Replication)

• Multiplexing for the Main Service Channel (MSC), Fast Access

Channel (FAC), and Service Description Channel (SDC)

• COFDM Modulation (Coded Orthogonal Frequency Division

Multiplexing)

• QAM (Quadrature Amplitude Modulation), and

• Interleaving.

From the beginning, a key objective in the development of DRM was to design a

digital system that works within the existing radio spectral mask without interference to

the current analog signal. This was important because it would enable maximum use of

the current AM spectrum without the need for any transition planning.

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When Will DRM Become a Market Reality?

As with any new technology, the question of when DRM will become widely

available to (and accepted by) listeners is one of the most important. Broadcasters will

need to implement DRM on the transmitter side—a process that will vary in cost and

complexity depending upon the AM transmitter and antenna system that is already in

place. Yet even when the DRM transmission infrastructure and programming are in

place, the broadcast audience will need to be compelled to invest in DRM receivers, the

final link in the air chain. Until there are sufficient listeners, DRM will remain in the

experimental stage.

To begin to predict when DRM will become a market reality, it is necessary to

consider two things—first, when receivers will be available, and second, factors that are

expected to compel listeners to invest in receivers in four defined “market groups.”

Let’s start with the receiver question: at this time, there are only specialty

receivers available. The first receivers were of test equipment quality and price. Now

there are at least two moderately priced receivers available. One enables the broadcaster

to listen to his transmissions and costs less than 1,000 Euros. The other, a software

package made available by the DRM Organization (www.drm.org) for 50 Euros, is ideal

for the technically inclined who already have a communications receiver want to

experiment with DRM reception. The DRM Organization anticipates that the first

commercial receivers will be introduced during 2004, with portable/mobile/car receivers

to follow a year later (in 2005).

DRM transmissions will ramp up with the commercial receiver launches, with a

gradual increase in program hours following receiver penetration. Although DRM

broadcasts have already started and business-to-business promotion efforts and

demonstrations already are underway in Europe and Asia, the early mass market will

develop in 2006. It is expected that a significant worldwide market for broadcasters,

service providers and receiver manufacturers will be in place by 2008.

But where, really, will DRM be established first? There appear to be four

different groups of countries or markets for DRM, each with its own characteristics.

Let’s briefly look at each of these groups:

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1) Saturated Radio Markets: This group includes countries where radios are available

to most (or all) people in various formats. Most households have more than one radio,

and there is a high penetration of car receivers.

In these markets, broadcast sound quality is very important to the listener,

who also has access to a variety of other media including home entertainment systems,

personal/portable sound media, Internet radio, and other developed sound information

and services.

These countries already have (or will shortly have) established digital sound

broadcasting systems against which DRM will have to compete. These countries also

tend to be highly regulated, which means that it will take time to implement forms of

DRM that require any reapportioning of the current frequency spectrum.

Because these countries tend to have higher disposable income, they most likely

will drive the first round of receiver development, since the first receivers will be higher

priced than their successors. These initial receivers will be used in the automobile and

the home.

2) Potential Radio Markets: Countries in this group have a structured radio

broadcast service in place and generally are highly regulated. While it may take time for

the regulatory bodies to accept the new technology, they will be motivated by the

opportunity to improve radio service and to offer higher quality over AM channels.

These countries tend to have less competition with other new and emerging digital

media, and drivers for DRM will tend to focus on improving the existing service rather

than on adding new formats and services.

These countries also will most likely push the development of lower-priced

portable and home receivers that are accessible to the masses.

3) Smaller Countries with High Income: In these countries where personal incomes

tend to be high, receiver price is not expected to be much of an issue. Countries in this

group tend to be developing rapidly and have a strong desire for news and other

information. Digital competition also tends to be less significant in these areas.

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Acceptance of DRM will be driven by available programming—possibly from

distant countries.

This group tends to be in line with early DRM adopters (Saturated Radio

Markets) and will be potential candidates for the initial higher-priced receivers.

4) Countries with Low Income: These countries have a high dependence on radio for

information and communication, and audio quality is less of an issue than in the other

groups. There is little competition for the average listener who tends to have a relatively

low income, and the price of the radio receiver is very significant. Therefore, while this

market is large, the transition will take time and most likely will only happen as the

popularity of DRM broadcasts drives the availability and the cost of receivers to the

current level of AM receivers worldwide.

These countries will be the last to accept digital radio—even though the large size

of this market makes it the most significant for the general acceptance of DRM.

DRM: One of Many Forms of Digital Radio Broadcasting

DRM is one of three digital systems currently being pursued by traditional radio

broadcasters. DRM and HD Radio (IBOC) are both in-band systems, and DAB (Eureka

147) is an out-of-band system. A brief overview of each system follows:

DAB (Eureka 147 Digital System) as a new transmission format in a new frequency

band:

• High quality digital audio

• Rugged, reliable delivery

• Flexible audio and data delivery

• Easy-to-use receivers

• MUSICAM® audio coding

• Multiple program delivery coding and multiplexing

• COFDM modulation

• Requires new frequency band

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HD Radio (iBiquity Digital System) for MW AM and FM

• Uses existing AM and FM frequency bands

• Designed to fit within 10 kHz (20 kHz total) RF bandwidth

• Hybrid (combined analog and digital) and All-Digital modes

• Allows for receiver transition planning

• Blends digital to analog in the Hybrid mode

• Digital quality FM stereo reception and high quality AM stereo reception

• Auxillary data services

DRM Digital System as originally designed for LW, MW, and SW services

• Uses existing AM bands below 30 MHz

• Fits within service in areas using 4.5 kHz (9 kHz total) or 5 kHz (10 kHz

total) RF bandwidth

• All-digital transmission with multiple modes for high quality signals or

difficult transmission conditions

• High quality mono sound

• Simulcast (analog and digital) transmission available, requiring additional

RF bandwidth

• Provides some data services

Harris—a company that has invested well over U.S. $60 million to offer the most

comprehensive portfolio of digital transmission technologies of any broadcast supplier, is

the only company to offer system solutions for DAB, HD Radio and DRM.

II. Upgrading the Transmission Chain to DRM

As broadcasters anticipate the eventual transition to digital radio, one of the most

important questions has to do with the transmitter. Obviously it is important to ensure

that the transmitter is capable of being upgraded for DRM simply and cost effectively in

the field. Not all transmitters that are in use today are capable of being upgraded for

digital operation, which depends on the ability of many individual DRM carriers

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(approximately 200!) to accurately carry digital bits over the assigned bandwidth. To be

DRM-capable, a transmitter must be able to meet stringent bandwidth, group delay and

noise specifications, and offer a wide-range output matching network.

Harris 3DX-50 AM Transmitter

This section will look at the suitability of the Harris DX Series all solid-state 10

kW through 2,000 kW transmitters for DRM. This line, which features Harris’ patented

Digital Amplitude Modulation, is the focus for two important reasons:

First, Harris DX systems are operating throughout China and, because of their

prevalence, it is likely that many will eventually be upgraded for DRM throughout this

country.

Second, DX transmitters are of special interest because they are the world’s

Number One line of Medium Wave transmitters. Well over 1,000 DX transmitters and

“power blocks” in high-power systems are on the air, and the number is continuing to

grow. These high-efficiency/low-maintenance transmitters are operating in environments

ranging from deserts to sea-sides to extremely high altitudes and under the most severe

conditions, including narrow band antennas, extreme high and low temperatures, high

humidity, and power lines with spikes, glitches and brown-outs.

Beyond operating flawlessly in the most demanding situations, these transmitters

were designed to be compatible with digital systems and therefore, they provide a simple

and cost-effective migration path to DRM.

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Following are details that show why DX transmitters are ideal for digital

operation in general and DRM in particular:

1) DX transmitters are inherently wideband. They provide both the wide RF

bandwidth and the wide AF (Audio Frequency) bandwidth essential for digital

transmission.

Wide RF Bandwidth: DX transmitters use multiple stages of Class D RF

amplifiers for high efficiency. A bandpass filter between each stage converts the square

wave into a sine wave for the next stage. By carefully choosing low Q networks, Harris

has designed the entire DX RF chain to be extremely wideband, from the external RF

input to the RF output.

Wide AF (Audio Frequency) Bandwidth: DX transmitters replace the traditional

transmitter modulator with a full 12-bit Analog-to-Digital converter (A/D). The A/D

converts the analog input signal to digital at either the carrier frequency rate or ½ the

carrier frequency rate (depending on the transmitter’s operating frequency). Multiple

low-power Read-Only-Memory (ROM) ICs (Integrated Circuits) decode the digital signal

from the A/D and provide “turn-on/turn-off” signals to multiple RF amplifiers whose

output is combined in a series combiner. The DX system of multiple ROMs and RF

amplifiers form a high-speed “Digital-to-RF” converter to create the modulated RF

output.

Additionally, the DX modulation scheme also eliminates the traditional

bandwidth-limiting low pass filter (and added group delay) used between the PA and the

modulator in a PDM transmitter.

2) DX Transmitters provide low group delay. With the combination of techniques

used to achieve wide RF and AF bandwidth, DX transmitters are highly linear. This is

the most important characteristic of a transmitter that is well suited for digital

broadcasting.

The DRM signal is complex. It contains both amplitude and phase modulation.

In order to amplify this signal in a high efficiency AM transmitter, the DRM exciter

breaks the DRM signal into two components. One is an amplitude component that is fed

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into the AF input of the transmitter. The other is a phase modulated RF signal that is fed

into the RF input of the transmitter in place of the usual RF source. In order to have a

low Bit Error Rate (BER) and a clean occupied bandwidth, the amplitude and phase

signals must arrive at the PA at the same time and with the correct amplitude for all

frequencies in the total occupied bandwidth. To accomplish this, it is necessary to delay

the modulation of the phase modulated RF signal.

Some modulators do not have a constant delay over the complete frequency

range, which could make them unsuitable for DRM. However, the modulator in the DX

transmitter has very little delay and is essentially constant.

DX-200 AM Transmitter

3) DX transmitters maintain superior SNR performance. Because DX transmitters

“turn on” (i.e., send voltages to) well-designed solid-state RF amplifiers in a

“thermometer approach” (i.e., RF amplifier #1 is always #1; RF amplifier #2 is always

#2, etc.) with sufficient cooling, module rotation is not required to prevent over-

dissipation. Superior noise figures are preserved—even at low percentages of

modulation. This is important because a high SNR can corrupt the digital signal and

increase the Bit Error Rate, eventually affecting coverage.

4) DX transmitters include an exceptional wide-range output matching network.

Designed to withstand VSWR conditions that will significantly compromise digital

performance, Harris DX transmitters contain a full wide-range “Pi” (shunt capacitor,

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series inductor, and shunt capacitor) output matching network with variable vacuum

capacitors and front-panel tuning and loading.

Low-Cost DRM Conversion Process for Harris DX Transmitters

Any DX transmitter can be converted to digital transmission quickly, easily and

cost-effectively using simple hand tools. The conversion process follows: (One

important note: While the example shows the upgrade of a DX 200, 200 kW transmitter,

the same process applies to any DX transmitter, regardless of power level. This is

because all DX transmitters feature the same architecture. Higher power DX systems

merely use more RF amplifiers with a bigger power supply and output network, while

lower power transmitters use fewer RF amplifiers in smaller units.)

Analog Input Modifications: The analog input board provides analog signal input

filtering, DC (carrier) power level control, and dither. The modification process follows:

Figure 1:

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Figure 1 shows the modulating analog input signal path. For digital broadcasting, the

modified Bessel filter must be bypassed. The transmitter should be jumpered for DC

coupled input since the exciter controls the DC (carrier power level) input.

The correct configuration is displayed in Figure 2:

• C20 through C23 is removed.

• L6/L8 and L5/ L7 are jumpered with a short circuit.

• JP7 and JP8 is moved from AC coupled 2-1 to DC coupled 2-3.

Figure 2:

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Next, since the exciter provides the DC input that controls carrier power, the DC level

normally supplied by the analog input board must be reduced. See Figure 3.

Figure 3:

At this point, measure the voltage at TP14 with a voltmeter. Record this voltage so if the

transmitter is returned to analog mode, the test point will need to be reset. Adjust R56

counter clockwise to minimize the voltage at TP14.

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A small amount of a 72 kHz “dither” triangle wave is added to the audio modulating

signal for normal operation. To meet DRM spectrum requirements, this signal must be

removed. Refer to Figure 4.

Figure 4:

Now, adjust R26 fully clockwise to minimize the dither signal to complete Analog Input

Modifications.

Oscillator Board Modifications: The oscillator board normally supplies the carrier

frequency signal used by the transmitter. It is replaced by the DRM exciter, which is

connected to the external RF input on the oscillator board. Refer to Figure 5.

Figure 5:

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Now, move jumper P3 from 1-3 (internal oscillator) to 1-2 to select the external RF input.

Jumper P3 can be used to provide a 50-Ohm or high resistance load for the DRM exciter

output.

Summary of DX transmitter conversion to DRM

The modification of a Harris DX transmitter for DRM operation can be completed

with simple hand tools. The process normally takes less than 15 minutes to complete. If

the station lacks a technical staff, these boards can be ordered from the factory through

Harris’ module exchange program.

III. An Overview: Harris’ DRM Product Portfolio

In addition to its DRM-capable transmitter lines (Attachment A includes an

overview of these lines which include DX, 3DX, and a new line of 1-6 kW DAX

transmitters), Harris offers three key DRM products.

These products include:

• The Harris DRM content server, which provides encoding for one audio service

and from one to four data services, multiplexes all of these services into one

signal, and generates the signaling information required by the receiver to

demultiplex and decode audio and data.

• The Harris DRM audio server, which encodes one optional and additional audio

service, and feeds the service multiplexer embedded into the DRM content server.

Up to three audio servers can be linked to a single DRM content server for a four-

audio service system.

• The Harris DRM modulator, which provides channel encoding and COFDM

modulation and feeds the AM transmitter with amplitude and phase signals.

High-level specifications are included in Attachment B.

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Figure 6 shows Harris’ total DRM encoding, multiplexing and modulation

system:

Figure 6:

AMTransmitter

DRMContent server

DRMmodulator

DRMAudio server

DRMAudio server

DRMAudio server

GUI(local or remote)

Audio

Data

Audio

Audio

Audio

TCP/IP

TCP/IP

TCP/IP

GUI(local or remote)

TCP/IP

Audio pre-processing

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In addition to its DRM-capable transmitters and products, Harris currently offers a

DRM Demo Kit for key customers who wish to evaluate the DRM performance of their

transmitters. Additionally, Harris will offer DRM Upgrade Kits for of its DRM-capable

transmitters and support services in mid-2004 in time for the launch of commercial

receivers.

A description of each kit follows:

Harris DRM Demo Kit: Although the kit does not include the full set of features

that will be available in Harris’ final DRM products, it does enable broadcasters to check

the DRM performance of their current transmitters and transmission systems in real-

world situations.

The Demo Kit includes:

• A basic DRM content server for encoding a single audio program and generating the

signaling information. This content server is implemented on a laptop PC.

• A basic DRM modulator for channel encoding, COFDM modulation and amplitude

and phase signal generation. This basic modulator can be implemented as a board that

replaces the transmitter oscillator board in DX medium power transmitters or in a 48

cm, 2RackUnit (8.9 cm) chassis that can be installed directly in transmitters (e.g.

DAX) or in a rack close to the transmitter (high power models).

• A test receiver with measurement capabilities from Fraunhofer (FhG Software Radio

for DRM transmission), implemented on a laptop PC, with a RF front-head from

AOR.

Harris Transmitter DRM Upgrade Kit: In mid 2004 in time for the first launch of

DRM receivers, Harris will offer a DRM Upgrade Kits for Harris AM transmitters

and upgrade services.

These kits will include Harris’ full-featured DRM content server, the DRM

modulator, the transmitter upgrade procedure and required parts. Available services will

include site review, training, transmitter upgrade and acceptance tests as needed.

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Conclusion

Even by the standards of today’s fast-paced world, DRM has developed rapidly.

In only five years since the first planning meeting in China, the standard has been

defined, the technology developed, and the first regular daily broadcasts initiated in

Europe, Asia and North America. The first fixed receivers are being introduced in 2004,

with portable/mobile/car receivers to follow in 2005. As early as 2008, it is expected that

a global market for broadcasters, service providers and receiver manufacturers alike will

be established.

There are probably many reasons why DRM is rapidly gaining a foothold:

First, by incorporating many of the most advanced technologies available, DRM

truly does provide the means to improve the quality and the service capability of AM

radio.

Second, DRM is an in-band system that preserves the worldwide frequency

allocation infrastructure.

Third, DRM is an open, non-proprietary and evolutionary standard..

Naturally, however, broadcasters and service providers must be concerned about

how they will eventually migrate to DRM. Many are wondering whether their current

transmission systems will be able to be upgraded, and others who are considering

investing in new systems want assurance that the equipment they purchase will not

become prematurely obsolete. To know whether transmission equipment is upgradeable,

broadcasters should pay careful attention to four important parameters—bandwidth (both

RF and AF), group delay, noise, and output matching network. These specifications are

key determinants whether a transmitter is suitable for DRM (or other digital) operation.

Since 1987 when Harris developed Digital Amplitude Modulation—the company

has focused on developing transmission equipment that provides a smooth and cost-

effective upgrade path to digital. Harris also has invested more than $60 million to offer

broadcasting’s largest range of solutions for digital radio and television broadcasting.

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As a result, the more-than-1,000 AM broadcasters worldwide who are operating

Harris DX Series 10-through-2000 kW transmitters, 3DX50 transmitters, and now Harris’

new DAX Series 1-6 kW transmitters are ready for the DRM future. Moreover, drawing

on its expertise in digital encoding, multiplexing, data broadcasting and modulation,

Harris is developing a full line of DRM products including a content server, an audio

server and a modulator. Harris is also offering a DRM Demo Kit that can enable key

customers to test DRM with their actual transmission systems now, and will release an

upgrade kit for Harris DRM-capable transmitters and support services in time for the

commercial launch of DRM receivers in 2004.

Dax AM Digital Transmitter

There is no question that DRM is a reality and one of the most exciting

developments in AM radio since its inception. Harris is ready and willing to be of

service as broadcasters transition to the dynamic and exciting future.

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Appendix A

Harris DRM-Capable Transmitters

Low power 1-6 kW

DAX Brand new modulation technology for high efficiency, superior performance and low cost of ownership in the low power segment

• Exceptional linearity and bandwidth • Digital Adaptive Modulation with digital

adaptative correction • Broadband design • High efficiency (75%-plus) • Compact design • Digital ready (IBOC and DRM) • Internal DRM modulator • Internal or external DRM content server

DX10/15/25/50 Harris patented Direct Digital Synthesis for high efficiency, high performance in the medium and high power segments

• Field proven technology (widest customer base in the world: 1500-plus units on air)

• High efficiency (80% plus) • Digital ready (IBOC and DRM) • Internal DRM modulator • External DRM content server

Medium power 10-50 kW

3DX50 New 3D Direct Digital Drive technology for highest efficiency and auto serviceability

• Exceptional linearity and bandwidth • Direct Digital Drive (no RF drives) • Auto servicing without reduction of the on-air

power (automatic module re-assignment) • Hot pluggable modules • High efficiency (88%-plus) • Digital ready (IBOC and DRM) • External DRM modulator • External DRM content server

High power 50-2000 kW

DX100/200/600 • Same technology and same user benefits as the medium power DX series

• Widest installed base worldwide • Available for LW transmission • External DRM modulator • External DRM content server

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Appendix B

Specifications: Harris DRM Products Content Server:

• Supports all audio encoding defined in the DRM standard (AAC, AAC+SBR, CELP, HVXC), for one audio service, at all encoding rates

• Support of all data applications defined in the standard

• Flexible data input format (TCP/IP based)

• Generates the DRM multiplex, including the mandatory signalization in FAC, SDC, MSC channels

• Supports MFN and SFN modes

• Output compliant with the DI (distribution interface) standard (IP over Ethernet)

• Synchronizable by an external GPS

• Local and remote GUI for configuration and control

• Support of dynamic reconfiguration

• Full compliance with the DRM standards

• 19” 2RU housing

Harris DRM Audio Server:

• Supports all audio encoding defined in the standard (AAC, AAC+SBR, CELP, HVXC), one audio service, at all encoding rates

• Output compliant with the DI (distribution interface) standard (IP over Ethernet)

• Synchronizable by an external GPS

• Local and remote GUI for configuration and control

• Support of dynamic reconfiguration

• Full compliance with the DRM standards

• 19” 2RU housing

Harris DRM Modulator:

• COFDM encoding and modulation fully compliant with DRM standard ETSI ES 201 980

• Supports all channel encoding rates

• Supports all constellations and mappings (non-hierarchical and hierarchical)

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Appendix B: Specifications for Harris DRM Products

Page 2

Harris DRM Modulator (continued)

• Supports all RF bandwidths

• Supports all MFN and SFN modes

• Available with digital mode and hybrid mode (simulcast) as an option

• Input compliant with the DI standard (Distribution interface, IP over Ethernet)

• Integrated GPS receiver for time and frequency synchronization

• Output interfaces: audio and RF

• Operational mode setting from the Content Server through the DI interface

• 19” 1RU housing or add-on board for Harris DX transmitters

• Local and remote GUI for configuration and control