Spatial multiplexing and Receive Diversity in Wimax Spatial multiplexing WiMAX also supports spatial multiplexing, where multiple independent streams are transmitted across multiple antennas. If the receiver also has multiple antennas, the streams can be separated out using space-time processing. Instead of increasing diversity, multiple antennas in this case are used to increase the data rate … Read more
Advanced Antenna Systems,Transmit diversity and Beamforming in Wimax Advanced Antenna Systems The WiMAX standard provides extensive support for implementing advanced multiantenna solutions to improve system performance. Significant gains in overall system capacity and spectral efficiency can be achieved by deploying the optional advanced antenna systems (AAS) defined in WiMAX. AAS includes support for a variety … Read more
What is Basic behind MIMO for LTE MIMO and other transmit spatial diversity scheme is a newer application than receive diversity and has become widely implemented only in the early 2000s. As the signals sent from different transmit antennas interfere with one another, processing is required at both the transmitter and the receiver in order … Read more
The effective Eb/No and hence the spectral efficiency depend on BLER. However there are QoS requirements which also have to be considered. Taking both into account leads to a target BLER. AMC is in use in order to tune BLER so that the target value is reached. Therefore when channel conditions change modulation and/or coding … Read more
LTE parameters Equipment related parameters include the base station, antenna, and terminal. The link budget parameters vary with the base stations, antennas, and terminals of different vendors. These parameters affect the link budget result. As a result, the downlink is unaffected in most scenarios. List of LTE parameters in LTE link Budget LTE Transmit Power LTE Power Combining … Read more
LTE devices use several modulation techniques to modulate data and control information. These modulation techniques include: QPSK (2 bits per symbol), 16QAM (4 bits per symbol), and 64QAM (6 bits per symbol). All of these modulation techniques are supported in the downlink direction; and all but 64QAM, which is optional, are supported in the uplink … Read more
Currently, beam forming is only applicable for TDD version of LTE. The time synchronous version of LTE TDD on uplink and downlink also makes the implementation of beam forming more attractive than in LTE FDD. Beam forming scheme is a signal processing technology that is used to direct radio transmission in a chosen angular direction. … Read more
The third assumption—that the background noise is Gaussian and uncorrelated with the transmissions—is especially suspect in a cellular MIMO system. All well-designed cellular systems are by nature interference limited: If they were not, it would be possible to increase the spectral efficiency by lowering the frequency reuse or increasing the average loading per cell. In the … Read more
Multiple antennas in LTE may also be used to transmit the same signal appropriately weighted for each antenna element such that the effect is to focus the transmitted beam in the direction of the receiver and away from interference, thereby improving the received SINR. The beam-forming weight vector should increase the antenna gain in the … Read more
Spatial multiplexing is where multiple independent streams are transmitted across multiple antennas. If the receiver also has multiple antennas, the streams can be separated out using spatial multiplexing. Instead of increasing diversity, multiple antennas in this case are used to increase the data rate or capacity of the system. In a rich multipath environment, the … Read more