Recommendation itu-r sm. 1538-1 Technical and operating parameters and spectrum requirements for short range radiocommunication devices




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3.4 Equipment for detecting avalanche victims


Avalanche beacons are radio location systems used for searching for and/or finding avalanche victims, for the purpose of direct rescue.

3.5 Broadband radio local area networks (RLANs)


RLANs were conceived in order to replace physical cables for the connection of data networks within a building, thus providing a more flexible and, possibly, a more economic approach to the installation, reconfiguration and use of such networks within the business and industrial environments.

These systems often take advantage of spread spectrum modulation or other redundant (i.e. error correction) transmission techniques, which enable them to operate satisfactorily in a noisy radio environment. In the lower microwave or in UHF bands, satisfactory in-building propagation may be achieved but systems are limited to low data rates (up to 1 Mbit/s) because of spectrum availability.

To ensure compatibility with other radio applications in the 2.4 and 5 GHz band a number of restrictions and mandatory features are required. Other studies on RLANs are going on in the Radiocommunication Study Groups.

3.6 Railway applications


Applications specifically intended for use on railways comprise mainly the following three categories:

3.6.1 Automatic vehicle identification (AVI)


The AVI system uses data transmission between a transponder located on a vehicle and a fixed interrogator positioned on the track to provide for the automatic and unambiguous identification of a passing vehicle. The system also enables any other stored data to be read and provides for the bidirectional exchange of variable data.

3.6.2 Balise system


Balise is a system designed for locally defined transmission links between train and track. Data transmission is possible in both directions. The physical data transmission path length is of the order of 1 m, i.e. it is significantly shorter than a vehicle. The interrogator is secured under the locomotive and the transponder is positioned at the centre of the track. Power is supplied to the transponder by the interrogator.

3.6.3 Loop system


The loop system is designed for the transmission of data between train and track. Data transmission is possible in both directions. There are short loops and medium loops which provide for intermittent and continuous transmissions. In case of short loops the contact length is of the order of 10 m. The contact length in the case of medium loops is between 500 m and 6 000 m. No train location functions are possible in the case of continuous transmission. The contact length is greater than in the case of intermittent transmission and generally exceeds the length of a block. A block is a section of the track in which only one train may be situated.

3.7 Road transport and traffic telematics (RTTTs)


(Also referred to as dedicated short-range communications for transport information and control systems (TICSs).)

RTTT systems are defined as systems providing data communication between two or more road vehicles and between road vehicles and the road infrastructure for various information-based travel and transport applications, including automatic toll-collection, route and parking guidance, collision avoidance and similar applications.


3.8 Equipment for detecting movement and equipment for alert


Equipment for detecting movement and equipment for alert are low power radar systems for radiodetermination purposes. Radiodetermination means the determination of the position, velocity and/or other characteristics of an object, or the obtaining of information relating to these parameters, by means of the propagation properties of radio waves.

3.9 Alarms

3.9.1 Alarm in general


The use of radiocommunication for indicating an alarm condition at a distant location.

3.9.2 Social alarms


The social alarm service is an emergency assistance service intended to allow people to signal that they are in distress and allow them to receive the appropriate assistance. The service is organized as any assistance network, generally with a team available on a 24-hour basis in a station where alarm signals are received and appropriate steps are taken to provide the required assistance (calling a doctor, the fire brigade etc.).

The alarm is usually sent via the telephone line, automatic dialling being ensured by fixed equipment (local unit) connected to the line. The local unit is activated from a small portable radio device (trigger) worn by the individual.

Social alarm systems are typically designed to provide as high a level of reliability as is practically feasible. For radio systems, the interference risk would be limited if frequencies were reserved for their exclusive use.

3.10 Model control


Model control covers the application of radio model control equipment, which is solely for the purpose of controlling the movement of the model (toy), in the air, on land or over or under the water surface.

3.11 Inductive applications


Inductive loop systems are communication systems based on magnetic fields generally at low RF frequencies.

The regulations for inductive systems are different in various countries. In some countries this equipment is not considered as radio equipment, and neither type approval nor limits for the magnetic field are set. In other countries inductive equipment is considered as radio equipment and there are various national or international type approval standards.

Inductive applications include for example car immobilizers, car access systems or car detectors, animal identification, alarm systems, item management and logistic systems, cable detection, waste management, personal identification, wireless voice links, access control, proximity sensors, anti theft systems including RF anti-theft induction systems, data transfer to handheld devices, automatic article identification, wireless control systems and automatic road tolling.

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