How to simulate multiple LTE user equipments (UE) in uplink with fading channel

Hi all,

I am trying to simulate LTE uplink with the following configuration: 2 UEs transmit to a single eNB. An UE is close to eNB and the other one is far.

I would like to know if there is some example in LTE system toolbox that shows how to build two uplink signals that use distinct resource blocks at the same time (FDD duplexing). Such that I can simulate one signal through an uplink channel, and simulate the other one in another uplink channel.

The main issue here is how to build an LTE signal composed of these two signals and then decode PUSCH bits from each UE from a single signal RX at eNB (this signal RX is the sum of the two uplink signals received over distinct channels).

Any comments or suggestions are welcome.

Thank you

[John BG]

There is an LTE toolbox, would you consider trying it you can install the 30 day trial, you may have to splash some cash but not much if you are student.

[Leonardo Ramalho]

Thanks John. I have the LTE toolbox. But I did not find any example of Toolbox that do what I asked above.

All the examples or tools from toolbox create a LTE uplink signal for one UE only. They do not have didactic examples of how to build an uplink LTE signal from two UEs and decode the bits for each UE.

Answer 1

[Kevin]

Hi Leonardo,

On the tx side of the uplink, I am assuming that you are able to create one resource grid for one UE for one subframe. In the context of the LTE toolbox, a resource grid is just a MATLAB matrix and let just call it G1 (for UE1). Most of the elements in this matrix G1 are zero except the elements used for the transmission of PUSCH and PUSCH demodulation reference signal. Then call the function lteSCFDMAModulate() to generate the complex baseband IQ samples from G1. Apply channel fading to this IQ samples.

Now do the same thing for UE2 (of course using different transport block) and you should have another resource grid for UE2. Let call this resource grid G2.

Now you can simply add these 2 IQ samples (going through its own channel fading) and this is your received signal.

Does this make sense? Am I on the right track?

Let try to do the tx and channel first. After that, we can do the rx side.

Answer 2

[ima ne]

Hi Leonardo Ramalho ,i'd like to know if u have realized this type of communication between two UEs and one eNB. I want to simulate minimum two UE ,but don't find any examples.Could u help me! Thank u

[giancarlo maldonado cardenas]

HI ima ne.

did you manage to solve any of this problem?

I managed to solve in part, we can get together to develop it.