LTE System Toolbox: What is the difference between the LTE Downlink RMC generator and the LTE Testmodel generator

I am currently working on a LTE receiver with the use of the LTE System Toolbox. To test the receiver I want to use the lteTestModelTool() function. To develop the receiver I use the example in: https://nl.mathworks.com/help/lte/examples/cell-search-mib-and-sib1-recovery.html

In this example they use the LTE Downlink RMC generator. I want to use the code in this example for the lte Testmodel generator, but when I use the Testmodel generator the PBCH is not decoded (MIB bits remain zero). To solve this problem I want to know exactly the difference between the LTE signals created by the Downlink RMC generator and the Testmodel generator.

Testmodel generator: https://nl.mathworks.com/help/lte/ug/generate-a-test-model.html

Downlink RMC generator: https://nl.mathworks.com/help/lte/ug/generate-lte-downlink-rmc-waveforms.html#bt88oux

[Varun Gunda]

The following link may help you: https://in.mathworks.com/matlabcentral/answers/321123-why-can-i-not-recover-the-mib-when-i-use-the-lte-downlink-channel-example-to-generate-waveform?s_tid=answers_rc1-2_p2_BOTH

[Meerten]

Sorry for the late reply (I am new with this platform). Thank you very much, very helpfull!

Answer 1

[Graham Freeland]

Hi Meerten,

The primary difference between RMC (Reference Measurement Channels)/FRC (Fixed Reference Channels) and the E-TM (Evolved Test Models) is that the test models don't include any transport channel encoding. They just push certain bit patterns through the physical channels and onto the subframe resource elements. The resulting waveforms are properly formatted, in terms of physical channel and physical signal placement, but there is no data encoding. The test models are also only single port.

Test models are intended to assess RF performance whereas RMC/FRC are for demodulation performance etc since they include the transport channel processing.

Note that the waveform generators in LTE System Toolbox are capable of generating more general LTE waveforms than just standard defined RMC/E-TM. A selected set of RMC/E-TM have been chosen as 'pre-canned' configurations to make it very easy to generate LTE signals out-of-the-box.

Cheers,

Graham

[Meerten]

Thanks, now it is totally clear to me!