Using Arduino Nano and NRF24l01+ as trasnmit and recieve only nodes

Hello, I am currently taking a project based on Arduino nano(ATMEGA328p) and NRF24l01+. So, my basic communication is like I have 2 transmitters which are only transmitters not a transceivers module and Receiver is used like an unidirectional nodes. Hence, 2 transmitters are communicating with one receiver is the basic version. Problems I am facing is it not able to transmit continuously as NRF24l01+ datasheet suggests that Transmitting cannot happen more than 4micrseconds. But my requirements are to make it transmit continuously. So, this is my one requirement. And another one is I am using 2 independent transmit nodes such that no interface between two nodes but I need to implement an algorithm which needs to be applied such that this two independent node should be controlled[i.e After my first transmitter finishes transmitting my second transmitter should start transmitting but they are independent of each other]. So, can any one suggest me how to apply these logic it would be of great help. I am using COM ports so can anyone tell me whether is it possible to control Arduino through COM ports connected. Thanking you in advance. Hope I conveyed everything so any things which aren't clear one can post. Sorry for my bad English