RE: The nRF905-EVBOARD

Suleyman — Thu, 22 Oct 2015 13:21:43 GMT

Hi, Ok I don'have anechoic chamber, but nothing prevent me doing relative measurement. I set the spectrum to fixed place and measure the values by an antenna (tuned to 868MHZ) connected to the spectrum analyzer. The antenna ot the transmitter and antenna connected to spectrum is 1cm .I do all my measurent at the same place same distance, even the board place on a fixed place. İnjecting 10mw of power to the antenna , and getting 1/20 of from the antenna (All parts are from eval kit , this can be seen by the range test as well compared with different brand 868Mhz chipsets). I did same measurement with different vendors transmitters. with same setup same distance. same place etc. I can see the bare difference .say the output of the chip is 16dBm directly measured with cable. with antenna the antenna at 1cm distance I get 11 dBm. From these comparative experiment I may say that the nrf905 eval board is not enough efficient. Then not enough to make evaluations. I think that nordic should provide anechoic chamber measurement in order to make real evaluation.

with my nrf905 I did about 50m range with obstruction. with the 16dBm module I get about 300m with obstruction. I need about 300 meters range line of sight) for my application which will be in industrial application like remote crane control ( we produce remote crane controller since 2006 about 50000 pcs of nrf2401A functionning in the market)

some suggestions please.

best regards

RE: The nRF905-EVBOARD

ketiljo — Wed, 21 Oct 2015 06:39:53 GMT

It would help if you can describe your setup when you do radiated measurements. You need a calibrated anechoic chamber (reflection free room) to do this properly.