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harrison0511
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Joined: 2014-06-23 06:27
Near Field Mode

Hi,

We are interested in using Near Field Mode. In this mode, how long (how many cm ?) does DA14580 connect together ? Roughly 2 -3 cm ? or 1 - 2 m ?

JE_Dialog
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Joined: 2013-12-05 14:02
Hi Harrison, it is difficult

Hi Harrison, it is difficult to put a specific number on range as thats got so many other factors which affect that. We specify a -20dBm reduction in output power.

BR JE_Dialog

Alex Luo
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Joined: 2014-02-28 19:16
based on sdk, how do change

based on sdk, how to change the output power level? set register or have api to change it? If reduce 20dB, the output about -20dBm, how far can be reached based on the pcb antenna?
If I want to reach about 2-3 meters LOS, could you advise how much dB reduction roughly?

Thanks.

BB_Dialog
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Hi Alex,

Hi Alex,

the DA14580 has only two power levels: 0dBm and -20 dBm.
The 0 dBm is the default setting, the -20 dBm can be set as follows:

SetWord16(RF_ENABLE_CONFIG13_REG, 0x0030);          // set Near Field Mode -20 dBm

Back to the 0 dBm setting: 
SetWord16(RF_ENABLE_CONFIG13_REG, 0xD030);          // normal 0 dBm mode

For a link budget of say 90 dB, the theoretical range (LOS) would be 100 meters.
For 70 dB (-20 dBm) , thetheoretical LOS range would be 16 meters.

 

Best regards, BB_Dialog.

 

Alex Luo
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Thanks BB.

Thanks BB.

Did you test DK Basic board with PCB antenna? I simplly tested with my iPhone5s, it coverage about 28 meters. Maybe something wrong? My target is >50meter LOS and 20-30m indoor. Any advices about it?

For simulating nfc, I want <2meters coverage without compromise of maximium coverage. Any suggestion?

Thanks,
Alex

Alex Luo
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Last seen: 2 years 1 week ago
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Joined: 2014-02-28 19:16
Thanks BB.

Thanks BB.

Did you test DK Basic board with PCB antenna? I simplly tested with my iPhone5s, it coverage about 28 meters. Maybe something wrong? My target is >50meter LOS and 20-30m indoor. Any advices about it?

For simulating nfc, I want <2meters coverage without compromise of maximium coverage. Any suggestion?

Thanks,
Alex

BB_Dialog
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Last seen: 1 year 4 months ago
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Joined: 2013-12-05 14:44
Hi Alex,

Hi Alex,

you could try to detune, mismatch the printed antenna on the basic DK board.

e.g. soldering a short wire (0.15 square millimeter thick) at the shunt inductor L2 posistion will give about 30 dB attenuation.
RSSI reading at 10 cm disance will be about -60/-70 dBm.

Or remove the coupling capacitor (labeled R3).  That will also result in 30/40 dB attenuation.

Best regards, BB_Dialog.

Alex Luo
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Last seen: 2 years 1 week ago
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Joined: 2014-02-28 19:16
Thanks BB,

Thanks BB,

For output power level and sensitivity, are they related to VCC? For example, 2V supply may output lower level? Please advice.

Thanks,
Alex

BB_Dialog
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Last seen: 1 year 4 months ago
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Hi Alex,

Hi Alex,

sorry, no. Sensitivity and Output power are not related to supply voltage. The RF circuits are supplied by LDO's.

Best regards, BB_Dialog.

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