Using the internet to get the message across

Today’s immediate need is for radio interoperability. Standards, industry and government initiatives are addressing the issue, but not entirely and, arguably, not quickly enough. It is important that standards are developed, and the efforts to define them are invaluable.

Future radio formats must have interoperability as a key attribute. Yet is interoperability solely achievable through costly platforms, complex systems and lengthy standards processes?

It is not. Interoperability can be achieved now. It can be realised cost effectively, within the existing radio network and using readily available products and technology. It does not require wholesale change and investment.

Interoperability requires, first and foremost, a change of purpose and mindset. We must be clear on our purpose: interoperability is a means to an end. The purpose is to connect a radio user, operator, dispatcher - whoever, to another user or service - wherever. That is true interoperability.

It is not the aim of this article to debate the different approaches to interoperability. Yet it needs to be made clear that operators and users do have a choice. With the right information, they can decide how to realise interoperability, to which level and at what pace and cost.

We are used to viewing radio networks as dedicated to a specific purpose: emergency services, transport, government, private operators, etc. Each is a more or less independent network with its own infrastructure and operations. It is imperative that these can become interoperable.

Yet interoperability is more than integrating disparate radio networks. Today, two-way radio is one of many technologies that provide a user access to a service (function, application, communication).

Where that service originates, or indeed who offers it, will not limit its availability. 3G (UMTS) and its UTRAN radio interface is a good example: 3G is defined by one standard, but that doesn’t restrict the user from accessing services outside that standard or network.

For two-way radio, this means also that a user no longer may need an actual radio to use a radio network: a dispatcher may use a PC console; an incident coordinator may use a mobile phone.

It is up to us to look beyond radio itself and take advantage of the capabilities on offer from today’s IT and telecommunications technology.

Radio-over-IP is just such an ‘enabler’, allowing users to communicate across networks and radio standards.

Figure 1: Interoperability ‘solutions’ versus interoperability enablers.

The client has a legacy of disparate communications systems that serve urban, rural and remote areas. Numerous radio networks are spread across the country, mainly in analog (VHF) technology. These serve a large number of users across various provinces.

The infrastructure differs across the provinces with some areas already having IP access while others do not. Some consolidation has taken place in past years. Common-design Wi-Fi radio links and Wi-Fi distribution points have been installed.

These provide rural and remote areas access to VoIP, data and fax services. They operate in point-to-point and in multipoint configurations, with links spanning up to 100 km.

The two-way radio networks themselves are not integrated with either wireless or wireline IP network(s). They continue to provide stand-alone radio communication and trunked radio.

The client’s long-term objective is a comprehensively integrated and cost-effective solution. Two-way radio and Wi-Fi, wireline telecoms and IT will each provide a different access method to a common IP-based backbone and beyond to the internet.

Users will be able to access both services and each other, beyond the radio network. Any limitations are given by the terminal, not the network.

Users will also be able to retain and use their ‘old’ equipment and upgrade when and how they choose.

Access will be transparent across networks, allowing, for example, a VoIP user to call a mobile radio, a radio user to access data services or a PC user to download data from a remote radio site.

On the radio side, traditional, dispatch-based and/or trunked radio services will continue to be supported, eg, for government, security and emergency services. Here, availability and coverage, reliability, robustness and security are vital.

The physical implementation will be through individual, defined projects. In parallel, ‘end of life cycle’ replacement of equipment will be used to upgrade sites. Each phase or project builds on the previous without creating redundant infrastructure or capabilities.

The key requirements are:

• integrate land mobile radio networks with the IP backbone;
• enable transparent access from/to other telecommunications and IT networks;
• support continued use of existing assets;
• maintain, support and further current operations and infrastructure;
• minimise upfront investments and/or lead times;
• maintain open design and continual cost control, contain overheads;
• readily accommodate change;
• support future capabilities including, among others, smart sensors and cameras;
• provide for enhanced dispatch, command and control and surveillance functions.

The plan starts by enabling individual radio sites (base stations) with RoIP. This allows base band content to be transported via internet protocol over an IP network. Information (voice, messages and data) is placed into IP packets, the universal transport ‘container’ on any IP network.

As a result, where this content comes from and where it goes is independent of the radio network. RoIP access itself is independent of radio standards, formats, even frequency allocations and digital or analog.

A ‘RoIP-enabled’ radio infrastructure is inherently robust, cost effective and largely futureproof.

Deploying RoIP to sites is straightforward and cost effective. A single RoIP interface unit is placed with each radio. A PC-based soft console provides operator control, without further HW required. With RoIP, each radio is simply a node on a ubiquitous IP network.

By connecting radio-over-IP (RoIP) devices to radios we effectively create a RoIP backbone for the radio network. This backbone can be extended by simply adding more RoIP-enabled radio sites.

It can be also extended in functionality by, for example, adding RoIP network repeaters/servers with SIP (VoIP) interfaces and other network functions. The implementation can be done at the pace and cost that suits the user, if need be one radio at a time.

Since the integration occurs ‘behind’ the radio, existing equipment such as analog radios can continue to be used. Upgrades can be done on a case-by-case basis rather than across all users.

A RoIP infrastructure will also support new, currently unavailable radios, formats and features without requiring network upgrades.

Figure 2: ‘Any-to-any’ interoperability using a structured, open RoIP system.

With RoIP, users will be able to connect from a suitable VHF/UHF radio to both IT and telecommunications users and services including the internet and PCs, PSTN and VoIP.

Operations benefit from enhanced functionalities. Operators can, for example, patch digital to analog radios, providing a very cost-effective form of interoperability within the network itself.

Since RoIP allows many functions to be PC based, organisations can use and integrate with a much larger range of applications. RoIP allows users to access the radio network from the internet.

A user can be literally halfway around the world on a laptop and still access a local user on a two-way portable.

With RoIP, the radio network becomes a two-way radio ‘interface’ to a much larger network and user base, spread out over a variety of networks and geographies.

Not only does the radio network become interoperable, it now gives users access to an abundance of capabilities, services and applications.

How this is achieved, the level and types of interoperability and the infrastructure required will be described in detail in Part II of this article.