What is isolation in MIMO antenna?
In the MIMO system, two or more antennas are used on both the transmitter and receiver sides. A critical point is to arrange compact antenna elements without impairing antenna performance and system requirements. To do that, mutual coupling or isolation between adjacent antennas is a key factor.
What is spatial multiplexing in MIMO?
Spatial multiplexing in wireless communications is based on multi-input and multiple-output (MIMO) technology where multiple antennas at both the transmitter and receiver are used to carry multiple data streams simultaneously within the same frequency band.
How does MIMO spatial multiplexing work?
Spatial multiplexing is a technique that allows each transmitting antenna to send multiple streams of data to many receiving antenna at the same time and via the same frequency within the same sector. The user equipment (UE) in turn decodes each stream of data and reconstructs the data into its original sequence.
How do you improve isolation between two antennas?
A standard method in improving isolation is to limit the radiation in the propagating direction and to increase the distance between the antennas. However, this method is not highly efficient because the area allocated to the antennas in mobile device is very small.
How is antenna isolation calculated?
Vertical isolation can be computed by the following equation [9]: IV [dB] = 28 + 40*log (dV / λ) – (GTx + GRx) (11). IV[dB]: isolation between vertically separated transmitter and receiver antennas.
How is antenna isolation measured?
Isolation between a GPS and WIFI antenna that are near each other will be on the order of 20-30 dB, with higher values being preferred. The method of measuring isolation is typically done by connecting both antennas to a Vector Network Analyzer, and measuring S12 (the transmission coefficient).
How are dual pole antennas used in MIMO?
As an alternative to spatially separated antennas, dual-pole antennas are increasingly being used in MIMO deployments, as the measured performance differences between the two antenna configurations are negligible in real world applications. Dual-pole antennas are a great solution in situations where only a single antenna housing can be installed.
What should be the spacing between an antenna?
The minimum spacing between antennas specified in industry literature ranges widely, from 3 to 7 wavelengths. In theory, one wavelength of separation should be sufficient, but it depends on the environment and the amount of signal scattering.
What should the angular separation of an antenna be?
Angular separation improves as the distance increases between the antennas in the system. The minimum spacing between antennas specified in industry literature ranges widely, from 3 to 7 wavelengths. In theory, one wavelength of separation should be sufficient, but it depends on the environment and the amount of signal scattering.