update doc/BUILD.md and doc/RUNMODEM.md to reflect develop/develop-nr merge...

update doc/BUILD.md and doc/RUNMODEM.md to reflect develop/develop-nr merge and latest merge requests affecting the build procedure

doc/RUNMODEM.md

@@ -20,13 +20,12 @@ See the [dedicated page](BASIC_SIM.md).
 
 # RF Simulator
 
-The rf simulator is a oai device replacing the radio heads (for example the USRP device). It allows connecting the oai UE and the oai eNodeB through a network interface carrying the time-domain samples, getting rid of over the air unpredictable perturbations. This is the ideal tool to check signal processing algorithms and protocols implementation.
+The rf simulator is a oai device replacing the radio heads (for example the USRP device). It allows connecting the oai UE (LTE or 5G) and respectively the oai eNodeB or gNodeB through a network interface carrying the time-domain samples, getting rid of over the air unpredictable perturbations. This is the ideal tool to check signal processing algorithms and protocols implementation.  The rf simulator has some preliminary support for channel modeling.
 
 It is planned to enhance this simulator with the following functionalities:
 
-- Support for multiple UE connections,each UE being a `lte-uesoftmodem` instance.
-- Support for multiple eNodeB for hand-over tests
-- Support for channel modeling
+- Support for multiple UE connections,each UE being a `lte-uesoftmodem` or `nr_uesoftmodem` instance.
+- Support for multiple eNodeB's or gNodeB's for hand-over tests
 
    This is an easy use-case to setup and test, as no specific hardware is required. The [rfsimulator page](../targets/ARCH/rfsimulator/README.md ) contains the detailed documentation.