I want to build a robot car with an camera gimbal on top of it. This robot and gimbal should be controlled wireless by a gamepad and the head tracking of an Oculus Rift. As it is with the Oculus Rift, it has to have a low latency. Now I am searching a wireless solution to send the control bytes (about 5 bytes with max. 1000Hz) from a computer to an Arduino. The latency has to be as short as possible (1-3 ms). I already searched and I found these RF systems:

Is there a better solution? Or which of the RF systems above is the best for my case?


2 Answers 2


5 bytes (8 bits) at 1kbaud (1000 Hz) means that the payload is 40 bits and this with my simple maths implies a minimum latency of 40 milli seconds. Given that the payload will need to be packaged like this....

  • Preamble to lock-in the receiver possibly as low as 24 bits)
  • Header (address of the receiver possibly 8 bits)
  • Payload ( 40 bits)
  • Error check (16 bits)

Total number of bits is 88 bits and at 1kbaud this is a latency of 88 milli seconds just to receive and check the data is valid.

Going at 10kbaud means a latency of obviously 8.8 milli seconds.

This device can transmit at 115.2kbps and has an output power of +8dBm so is a more likely contender and here is the matching receiver module: -

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I've not gone into looking at these in any technical detail but they do seem the sort of module to use. They are FM too so there's a couple of dB more resilience for the same transmit power/ distance compared to AM.

  • \$\begingroup\$ Thanks for your answer. What are the advantages to the RFM22B module? Wouldn't the nRF24L01+ and nRF24LU1+ modules have a lower latency, because they are working on the 2.4 Ghz frequency? \$\endgroup\$
    – JoLau
    Jun 14, 2014 at 15:21
  • \$\begingroup\$ @JoLau There's going to be a bit of sophisticated silicon between the data port and the rf stuff on the Nordic module and there's no guarantee what length of preamble it might use. On the more basic module (generally) you can define this preamble to be as short as you can get it to lock in the receiver. Shop around and read the data sheets to see what the receiver lock-time is likely to be. Maybe the Nordic is good? It's not down to the operating frequency usually - it's down to the type of data slicer they use for reconstructing the data from the demodulated carrier. \$\endgroup\$
    – Andy aka
    Jun 14, 2014 at 15:50

One of my co-worker suggested to use Bluetooth modules of the company u-blox, because they are low latency and also optimizable. I used two connectBlue OBS421I-26-0 and one connectBlue ACC-34. The ACC-34 is just a serial-to-USB adapter to connect the Bluetooth module with the stationary PC.


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