Duplex communication with VirtualWire and two frequencies?

Projects Networking, Protocols, and Devices
1

I would like to build group of devices communicating by radio data link in following configuration:

There is one "Base station" (Arduino Uno) - it has 433MHz transmitter and 315MHz receiver
There are many "Client stations" (Arduino Nanos) - each has 433Mhz receiver and 315Mhz transmitter

Based on that I would like to create protocol using VirtualWire.h messages. Each message would contain address (number) of device it is addressed to, and sender address (number).
Base station would send commands to clients like TURN_RELAY_ON, TURN_RELAY_OFF, the client stations wold report relay status and send back some more sensors data (specific usage is not relevant to my questions).

Questions are:

  1. Is above scenario possible with VirtualWire and cheap receivers and transmitters working on 433MHz and 315MHz? Can VirtualWire be configured to listen using one freq and receive using another?
  2. Are there any simpler solutions for achieving above communication scenario? We could assume that "Base station" is alwas initiating communication (sends first message), and client stations report afterwards.
2

We could assume that "Base station" is alwas initiating communication (sends first message), and client stations report afterwards.

That would be my approach, or at least have some form of telling the slaves when to transmit. If they can just do their own thing how will you sort out the mess at the master end when they all talk at once?

Rob

3

Graynomad:

We could assume that "Base station" is alwas initiating communication (sends first message), and client stations report afterwards.

That would be my approach, or at least have some form of telling the slaves when to transmit. If they can just do their own thing how will you sort out the mess at the master end when they all talk at once?

Rob

My approach would be to ask specific slave (one at a time) for reporting sensor value. Each slave would be identified with a number (address). Master would send ASK- message, and only the slave with matching would respond.