As for my study project about UWB distance measuring with PA, i took APS004 as my reference.
However, the firmware on STM32L4A6VG which works properly on the DWM3000 but fail on DW3210. My schemetic for DW3210 is similar with the DWM3000 and merely adding PA circuit reference with APS004.
If i implementing a combination of DWM3000 and the board of DW3210 with PA, they could do ranging some time within 5m and the RSSI is -83dB.But if I implement the combination of both anchor and tag using DW3210 with PA, the communication fail and the MCU stuck in a loop with DW3210 and never come back.
In both case above,the GPIO5 and GPIO6 could not generate a logic high signal to open the RF switch and the LNA. Moreover, DWM3210 stuck in a loop while causing my MCU also stuck in a loop. What factor may cause this problem and how could solve it?
LNA:BGB707L7
RF switch: MASW-007107
Attentuator:GAT-8+
LDO:LP59073-3
MCU: STM32L4A6VG
Hi @lschanaf
hard to say what is wrong, but do you use channel 5 or channel 9?
You are mentioning PA but APS004 refers to LNA and not PA.
In my opinion try to remove the attenuator and try it again, if you need to use LNA then you don’t need to take care about short distances.
You are mentioning that the DW3xxx cannot drive the LNA and TX switches - the DW3xxx cannot drive high currents (barely few mA), for driving the TX switches it is OK but how do you drive the LNA?
Cheers
JK
Thank you for the quick response for my question.
I am using channel 5 in my design.
In datasheet of DW3000, the output current could reach 0.8mA , in theory the GPIO output current is enough to drive the RF switch(1uA) and the LNA(20uA).
About the LNA, it has a VCC input pin and a logical input pin. For the VCC pin ,i connect it with my main power source LP59073-3, and connect GPIO5/6 to the logic input pin. The GPIO5/6 in the DW3210 only connect two Rf switch and one LNA. It should be fine according the datasheet but reality is the IC can not drive a high signal to these components.
Hi @lschanaf
the DW3K should be able to drive those signals. Could you disconnect the DWM3120 and use external voltage with amperemeter to see if the current is at expected level?
Does your design have integrated antenna or do you use SMA connector? Could you check how the signal looks with the Spectrum analyzer?
Cheers
JK
Thank you for the response. After removing the attenuator from my design. The system finally could opearating normally when they have stable connection. The average RSSI is about -45dB in 1 meter.
But another question pops out that i can not figure out what factor cause the problem - My board is difficult to communicate with each other, it seems they can not find each other even they are in close distance. When i tried using DWM3000 on one side , another side using my board , the communication could establish easily and work properly. But if I changed both side are my DW3120 with LNA board, they can not establish the connection. But putting them running after a radom long time, they could suddenly making a stable connection without disconnecting.
Do this problem may causing by the RF delay or some protocol issue? I can not figure out and can not find a way to solve it.
Hi @lschanaf
without proper tools it is hard to say what is wrong. It could be also a protocol issue.
Just a few questions:
- What it your output power? (try 0xFFFFFFFF, maximum power)
- What is your PG delay? ( try 0x34 most common value)
- Have you trimmed Xtall offset? (this needs to be measured)
Cheers
JK