Dear Balam 

                  IF you are familiar with OMNET++ then there is a module "Castalia" which integrates with OMENT++ and provide support in terms of protocols for WBAN plus there are example scenarios of BAN . You may look at my following paper (full text available on RG ) where we have use Castalia.

1) A Novel QoS Algorithm for Health Care Applications of Body Area Sensor Networks

2) RPRP: Routing Protocol to ensure the reliability in health care systems.

Dr Adnan Nadeem

You can Use NS2 or Qualnet . Best regards 

You can use Qualnet,, Users can evaluate the basic behavior of a network, and test combinations of network features that are likely to work, simple and easy to use.

The QualNet® communications simulation platform (QualNet) is a planning, testing and training tool that "mimics" the behavior of a real communications network. Simulation is a cost-effective method for developing, deploying and managing network-centric systems throughout their entire lifecycle.

You can use Castalia , it is a simulator for wireless Body Area Networks (BAN) , its features include:

-  model for temporal variation of path loss

-  fine-grain interference and RSSI calculation

-   Physical process modeling, node clock drift, and several popular MAC protocols implemented.

-   It is highly parametric. It provides tools to help run large parametric simulation studies process and visualize the results.

I recommend OMNET++ for this purpose, check this link. 

https://omnetpp.org/doc/omnetpp/tictoc-tutorial/index.html

You can look at this post https://www.researchgate.net/post/Please_suggest_best_simulator_tool_for_Wireless_Body_Area_Network

Nice Dear Muneer Bani Yassein

i suggest " Castalia"

you can install omnet 4.6 and under it you install Castalia 3.3 (it's a simulator of WBANs and it contains many modules programmed with C++ language) you can use the configuration files and you can use an example BANtest to know how ti simulate the network and how to add new nodes or sinks.

Good Luck

This is something I found on WBAN simulation https://support.tetcos.com/support/solutions/articles/14000106347-wireless-body-area-network-wban-application-reading-sensor-measurements-from-a-csv-xl-file