To understand the impact of the channel, let’s assume that the base station receiver is facing many challenges in the same MIMO receiver that universal areas, but also must receive data simultaneously from multiple users. In terms of MIMO UM, each signal is derived from a separate UE, because each signal is completely independent channel, slightly different power levels and different time. These features can be emulated Agilent N5106A scanning a MIMO receiver (PxB), in combination with the RF signal generator.
Testing : Affects of the Channel in LTE MIMO
Test Configuration ENB receiver configuration differs from the UE. UE normally sends error reports in the uplink packet back to the test system and base station equipment is more likely that the appropriate demodulated output signal available.
Note that the recovery of the MIMO channel separation involves several components of the signal in the presence of noise and interference. When the transmitted signals are orthogonal, but once you get a lot of signal coupling path radiation receivers can reduce the difference between the signals.
Normal Operation: Affects of the Channel in LTE MIMO
In normal operation, the receiver will have to deal with complex and change the channel, but the channel fading by such means, testing is not repeatable, if you want to ensure that the basic bandwidth action is appropriate. Fading channel constructed from phase differences and simple for roads, provides deterministic signal may be designed to check the capacity limit of the receiver. Adding noise to the channel may be easily creating a control signal, wherein some subcarriers are harder than other demodulation.
In order to test the dual phase line source standard RF bandwidth and transient that can be achieved by means of a common reference frequency signal and the frame synchronization is sufficient for most applications.
If necessary fading configuration such as shown offers more ways off independent constant output analog or digital tester using Agilent N5106A MIMO receiver.
Direct MIMO: Affects of the Channel in LTE MIMO
For direct MIMO mapping test phase relationship between the open loop test signals do not affect the receiver, because the signals are orthogonal to connect adding twice the vector to occur. In a closed loop system, the phase of test signals must be constant when the channel is sampled, allowing the first coupling coefficients to be calculated and applied. This may require the system to be stable than phase.
The number of channel condition can be used to determine the SNR required achieving a specified performance de modulator. Number state is a composite measure of performance channel. Each layer of MIMO may, in fact, different performance.