Powershell to Meterpreter

Hi guys,

I manage to get powershell session with netcat, my problem is there a way to get meterpreter session over powershell. I manage to bind my netcat session with metasploit /cmd/unix/reverse_netcat.However when I use post ......./...../ shelltometerpreter I get error saying "you cannot upgrade unix command session to meterpreter at this time." is there any other way to get meterpreter session like powershell commands NOTE:I am doing this over WAN.