Page History

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• High interference - the influence of third-party wireless data transmission systems that use same frequency channels.
• Inefficient use of the input power - often the input power is used inefficiently due to the antennas weak directional properties. This factor also leads to interference.

Системы связи без использования технологии формирования луча

Диаграмма направленности антенн устройств, не поддерживающих технологию формирования луча, является фиксированной и не может быть изменена в процессе передачи данных. Пример работы сектора базовой станции, к которому подключены три абонентских устройства, представлен на видеоролике 1.

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Communication systems without beamforming technology

The antenna's radiation pattern without beamforming technology support is fixed and cannot be changed during data transfer. An example of the base station sector with three subscriber devices is shown in the video 1.

The base station sector consistently exchange data with the subscriber devices bidirectionally: the sector transmits data to the subscriber device 1, waiting for a response from it, then performs data exchange with the third and second subscribers. Downlink messages transmitted from the base station to the subscriber are received by all subscriber devices, regardless of the recipient, i.e. message sended to subscriber device 1, will be received by subscriber devices 2 and 3, but will not be processed.

Такой подход имеет несколько недостатков:

• Неэффективное использование мощности излучения (независимо от устройства-получателя, сектор выполняет передачу данных всем абонентским устройствам, попадающим в зону покрытия), т.е. энергетика канала связи с конкретным абонентским устройством может быть увеличена.
• Низкий уровень безопасности (получив доступ к одному из абонентских устройств, злоумышленник может перехватить весь исходящий трафик сектора для любого из абонентов).
• Появление локальной помехи на сектор оказывает влияние на работу всех абонентских устройств, подключенных к этому сектору.

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This approach has several disadvantages:

• Inefficient use of radiation power (the sector performs data transmission to all subscriber devices that are within the coverage area, regardless of the recipient device), i.e. the link power with a specific subscriber unit can be higher.
• Low security level (by gaining access to one of the subscriber devices, the attacker can intercept whole outgoing traffic of the sector for all subscribers).
• The appearance of local interference on the sector affects all subscriber devices operation connected to this sector.

Video 2 shows the operation of the base station sector with three subscribers, under the local interference conditions. At time intervals allocated for uplink data transmission, the sector receives the sum of the subscriber signal and interference. In case of high interference level, the sector cannot separate the useful subscriber component from the sum of received signals and the data transmission must be repeated. It will take extra time, i.e. system resources will be used inefficiently. Note that the interference signal in the sector coverage area affects the operation of all subscribers, since the wide radiation pattern main lobe does not allow selective spatial suppression. In other words, any signal into the main lobe of the sector radiation pattern will influence the entire system operation.

Технология формирования луча

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