Wireless Communications

In a world of increasing mobility, there is a growing need for people to communicate with each other and have timely access to information regardless of the location of the individuals within a terminal, station or train. A phone call placed from passenger may close a business deal, remote access to medical records by a paramedic may save a life, or a request for updates by a police officer with may affect the outcome of an incident.

Firstco offers wireless Communications solutions in the following areas:

• In Building WLAN
• Distributed Antenna Systems (DAS)
• GSM-R (Global System for Mobile Communications - Railway) coverage

WLAN solutions

Wireless Local Area Networks (WLANs) have become an essential part of any modern building communications infrastructure. Wi-Fi technology is widely used to support users in a variety of environments, from airports to conference centres to universities and corporate offices. The improvement of WLAN technology (such as with the introduction and adoption of the new 802.11n-draft standard) is expected to give WLAN utilisation a significant boost and allow it to take over services traditionally supported only by wired LANs.

Firstco offers WLAN system design solutions with the following characteristics:

• Resilient coverage: the system can be designed in a way that avoids single points of failure and guarantees a minimum level of coverage in case of component failures.
• Centralised architecture: The WLAN network uses central intelligent units to drive “thin” Access Points, transferring wireless traffic over the fixed LAN. Wireless data is segregated from the rest of the network traffic using virtual tunnelling from the Access Point to the central units.
• Seamless client roaming: The Access Points are deployed and configured in a manner that guarantees the seamless handover between one Access Point to another, preventing loss of connectivity or throughput degradation.
• Services prioritisation: Intelligent bandwidth allocation and service prioritisation can be used for effective QoS management of interruption sensitive services such as VoIP and VioIP.
• Intrusion detection and security: Intelligent Access Point configuration allows for the quick identification and suppression of “rogue” clients and intruder devices. The use of “thin” Access Points means that all data processing effectively takes place in the core of the system, resulting in increased security.

The basic components of a WLAN system are the following:

• Access Points: They provide the interface between the wireless client and the fixed LAN. Combinations of the various WiFi standards can be supported by a single Access Point. They usually come with in-built antennas but external antennas can also be used to achieve the desired coverage characteristics.
• Fixed LAN: All data passing through the Access Points is transferred over a fixed LAN to the core of the WLAN, the wireless controllers, where it is processed and routed back to the Access Points or to other devices connected to the LAN. All traffic between the Access Points and the core of the WLAN is completely segregated from the rest of the data in the LAN.
• Wireless Controllers: These devices form the core of the WLAN and perform all the processing of the wireless data traffic. They reside logically within the fixed LAN and are responsible for the control, monitoring and configuration of the Access Points.

DAS solutions

Firstco offers Distributed Antenna System (DAS) design solutions to enable (Private Mobile Radio) PMR and Cellular terminals to operate seamlessly throughout buildings, tunnels or any other complex. Firstco are vendor independent and therefore review and choose the most reliable equipment from the market to suit your needs.

A DAS solution has the following attributes:

• Guaranteed Coverage
  • A building or complex façade may attenuate external signals and prevent reliable operation of wireless equipment. A DAS will re broadcast within the building thereby eliminating this problem.
  • External signals cannot penetrate into basements, tunnels and metal clad corridors. A DAS will re broadcast within the building thereby eliminating this problem.
• High Capacity
  • Buildings may contain a large number of cellular and Private Mobile Radio (PMR) users requiring the addition of base station and other equipment to support them. A DAS will ensure that the users will preferentially associate with this equipment ensuring that nearby base stations do not become overloaded.
• Integrated Solution
  • The large number of operators and services can result in problems of management, control and maintenance. A DAS managed by a single body will ensure operator equipment is placed in a single location. These Operators will not have physical access to other parts of the DAS.
  • Traditional systems have operator equipment installed at many locations within buildings resulting in issues of power, space, access and cooling. An DAS will eliminate duplicated elements of traditional systems by the use of single antenna infrastructure.
  • Installation of several antenna systems can result in architectural design problems. A DAS system will minimise this equipment and may result in the system being more aesthetically pleasing by minimising visual intrusion and accommodation requirements.
  • Indoor wireless distribution antenna systems are complex and expensive to install. An DAS can result in a lower cost per operator as its costs may be divided amongst them.
  • Traditional systems result in different levels of coverage for different operators due to different positioning of antennas and feeders. An IBDAS will ensure all operators will have equal coverage thereby eliminating discrimination

A DAS consists of active and passive components to amplify, filter and radiate RF signals throughout its area of coverage. These include

• Passive Radiating Infrastructure - Radiating cable, antennas, couplers, splitters, combiners and associated equipment required for the transmission and reception of radio signals.
• Multi Service Combining - The combining systems form the hub of the DAS and enables several systems to be combined to enable effective transmission of the RF system.
• Active RF Transmission and Amplification system.

GSM-R solutions

Global System for Mobile Communications - Railway (GSM-R) is built on GSM technology and benefits from the economies of scale of its GSM technology heritage.

GSM-R is aiming at being a cost efficient digital replacement for existing incompatible in-track cable and analogue railway radio networks. Network Rail are in the process of upgrading their existing analogue radio systems to a digital GSM-R network.

GSM-R shall create a single standardised communications network with higher security and shall also ultimately enable more integration between signalling and other systems.

Firstco have been working with Heathrow Express and in partnership with Network Rail to develop a high level network solution that could enable GSM-R coverage within the Heathrow Express tunnels and its associated rail stations.

Heathrow Express currently use the Ultra High Frequency (UHF) Cab Secure Radio (CSR) System and would need to upgrade to GSM-R in order to have a seamless communication system with the signallers when travelling on the Great Western Main line and Heathrow Express tunnels.

Following agreement on the solution and scope of activities, Firstco have been tasked by Heathrow Express to provide a detailed design for enabling the GSM-R network rollout and keeping the CSR operational in parallel until the migration occurs.