Has anyone been successful in making a 1 watt of higher power version for Halowlink?
Or if someone willing to make one/ collaborate.
Team Morse, if you are open to making a higher power one, please count me in.
As of today there are no 30dBm (1W) modules available - but I’m sure that gap will be filled soon.
Quectel have a 27dBm (500mW) module available - https://www.quectel.com/product/wi-fi-halow-fgh100m-h/, which has been used on the Seeed Studio miniPCIe cards. This would work on single board computers or products which expose SPI lines on pins 45,47,49,51 of the mini pcie connector. A non-standard pinout, but it does exist.
I’m working on a PCB that should reach 30dBm, but to do this and remain within FCC limits, the board must use closed loop power control. The MM6108 doesn’t really support closed loop power control, so I’m designing an external power monitoring circuit so that the host MCU can control the amount of input power to the PA using an external attenuator. This should more or less control the power on an average basis, but cannot react fast enough to control the power on each packet burst. This circuit will not be low power or low cost and is targeted as an AP.
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Were you able to prototype this?
It is in the works. I’ve been delayed a bit due to a move. Had to take down my lab and move to a new location. The frontend looks pretty solid and I think it will come down to the controller and firmware. Since I can’t buy chips directly, I’m having to buy modules and float the chips off and place them on my PCB. Which MCU/controller are you using or are interested in?
I was using halowlink1 directly. As it was a ready to uses setup to try halow.
Anything Linux based would be ok, that can do mesh 802.11s
The MCU that I’m prototyping with is the STM32U575ZIT6 based upon the MM6108-EKH08, so it’s a STM32CubeIDE environment for firmware. I suppose a board spin could easily put it on a Pi Hat to get you into Linux.
The RF frontend has an analog signal which is proportional to the output power during a Tx burst that needs to be monitored with a 12bit ADC, triggered by the MM6108 Tx state. It also needs an SPI type interface for the digital attenuator which controls the input power to the PA. The STM32 provides these connections, so a similar set of connections would need to be implemented on the Raspberry Pi. Let me know if that would work for you or if you had something else in mind.
Normally, this kind of closed loop power control would be calibrated with a power meter as the attenuator is swept over the useful power range, so the attenuator settings associated with power levels are stored in a LUT. This creates a correlation between the power levels read by the log amp on the board, the attenuator settings and the measurements made with the power meter … and then there is compensation for temperature and voltage variations, but that would probably be more for a commercially available and FCC certified module. For prototyping, just 25 C and stable supply voltage could be assumed.