Throughput and BER test with nRF24L01+ radio and Teensy microcontroller I am trying to modify the example given in the this page to a basic throughput and BER test with two nRF24L01+ and Teensy 3.0 modules. 

I want to modify the nrf24l01_send_string example in a way that I can remove the powerUp powerDown and delay and transmit the next packet purely based on the ACK received from the receiver. The problem is RF24 class does not seem to have a method to transmit ACK (not ACK+Payload) and the datasheet does give any information on the structure of the ACK message. The example works when powerUp and powerDown are removed, but I need to modify it to measure throughput by removing the delay.
@Gerben remarked:   


  You can't send the ACK manually. The module itself sends the ACK
  automatically (if enabled that is), once it receives the package. This
  way the sending module only need to be listening for the ACK for the
  shortest amount of time, reducing power usage. To attach data to the
  ACK package you need the writeAckPayload function. But you have to
  prepare this before any package is received