This is regarding a wireless logger application: My final target application would require very small size of the part that will transmit data most of the time and will require a ceramic chip antenna; the receiving download station could be bigger and accept a duck antenna, at least 10cm long, perhaps even 20cm length. I only need short range of 10-20cm, however the medium transmitted through will not be very favorable, in fact the first goal will be to determine if it is possible at all at this frequency.
I have read some of the threads like this one,
viewtopic.php?t=6353&highlight=mirf++umirf which indicates that nRF24L01 is a better chip than nRF2401A. However I am uncertain about the short range reported for the MiRF v2 with ceramic chip antenna. Size is also an issue, however the board of MiRF v2 should be just acceptable. Power consumption in the logger/transmitter part would be very important due to small size and low battery capacity.
So how would two uMiRF’s measure up against a pair of MiRF v2, one with ceramic chip and the other with duck antenna?
It could seem as if the MiRf v.2 could be optimized more by removing the ground trace beneath the ceramic antenna. As it is now, it could seem it would suffer some from having the same PCB as the version with the antenna connector (as far as I can see from the images that is the reason for that trace).
I will always recommend the 24L01 over the 2401 (as I did in the post you linked). Removing the ground plane from the MiRF-v2 could certainly help out on distance, and is worth a shot. But when it comes down to it, the “unfavorable medium” that you are transmitting through might hinder a 2.4 GHz unit considerably, as waves at that high a frequency get attenuated quickly by walls, etc. You may end up having to go with a lower frequency RF unit depending on your needs, but I feel that the 24L01 is a good unit to work with. Plus I have a ton of info and source code for interfacing to it on my website.
Thanks for the response. Yes, the first stage will be to see if it can work at all through the unfavorable medium, and then go from there. The uMiRFs are being returned in in their sealed envelopes to be replaced by MiRF’s v2, one with duck antenna and one with ceramic chip antenna.
BTW the Nordic data sheet has a layout for a module with SMA connector that is very compact (only 10.6mm wide). Perhaps that could have been modified to make a uMIRF v 2 with chip antenna?
