Single antenna interference cancellation

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Single antenna interference cancellation (SAIC) is a technique used to boost the capacity of global system for mobile communications (GSM) networks without any other changes needed in the network. In a GPS network, there is a trade-off between downlink capacity and interference level. To optimize this trade-off, the mobile station (i.e. a cell phone) must exploit a property of the interferers. The techniques used to do this are commonly referred to as single antenna interference cancellation. [1] [2]

Use

Network operators want to use the allocated spectrum as efficiently as possible and to the highest possible capacity, to maximize the return from the investment into the license for it. The ideal frequency reuse is one, meaning that each cell can operate at the same frequency. This in turn creates interference to users operating in nearby places. Increase Interference causes voice quality to drop and may cause call drop. It is possible to cancel the interference at the mobile handset side by changing the baseband software without changing anything at the network side. SAIC-enabled mobiles can work at high levels of interference, and need less transmit power from the network, which in turn reduces interference in the network. Studies shows that the speech quality gain can be about 6% at a SAIC mobiles penetration of 10%, about 37% at a SAIC mobile penetration of 50%, and about 99% at a SAIC mobiles penetration of 100%.

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The Global System for Mobile Communications (GSM) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation (2G) digital cellular networks used by mobile devices such as mobile phones and tablets. It was first deployed in Finland in December 1991. By the mid-2010s, it became a global standard for mobile communications achieving over 90% market share, and operating in over 193 countries and territories.

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Base station subsystem

The base station subsystem (BSS) is the section of a traditional cellular telephone network which is responsible for handling traffic and signaling between a mobile phone and the network switching subsystem. The BSS carries out transcoding of speech channels, allocation of radio channels to mobile phones, paging, transmission and reception over the air interface and many other tasks related to the radio network.

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Cellular network Communication network

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GSM radio frequency optimization is the optimization of GSM radio frequencies. GSM network consist of different cells and each cell transmit signals to and receive signals from the mobile station, for proper working of base station many parameters are defined before functioning the base station such as the coverage area of a cell depends on different factors including the transmitting power of the base station, obstructing buildings in cells, height of the base station and location of base station. Radio Frequency Optimization is a process through which different soft and hard parameters of the Base transceiver stations are changed in order to improve the coverage area and improve quality of signal. Besides that there are various key performance indicators which have to be constantly monitored and necessary changes proposed in order to keep KPIs in agreed limits with the mobile operator.

Self-interference cancellation (SIC) is a signal processing technique that enables a radio transceiver to simultaneously transmit and receive on a single channel, a pair of partially-overlapping channels, or any pair of channels in the same frequency band. When used to allow simultaneous transmission and reception on the same frequency, sometimes referred to as “in-band full-duplex” or “simultaneous transmit and receive,” SIC effectively doubles spectral efficiency. SIC also enables devices and platforms containing two radios that use the same frequency band to operate both radios simultaneously.

References

  1. Chang, Chung (May 2005). "Single Antenna Interference Cancellation in Asynchronous GSM/GPRS Networks" (PDF).{{cite journal}}: Cite journal requires |journal= (help)
  2. Andrews, J.G. (April 2005). "Interference cancellation for cellular systems: a contemporary overview". IEEE Wireless Communications. 12 (2): 19–29. doi:10.1109/MWC.2005.1421925. ISSN   1558-0687.