Is it possible to use bcm43438 for other frequencies?

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Anonymous
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I am interested in the question of whether it is theoretically possible to use the bcm43438 chip on other frequencies than 2.4G and 5G, which is presumably equivalent to the question of whether the band filtering is done in hardware inside the chip, in software inside the chip or in hardware outside of it.  I am fully aware of (and have no intention of ignoring) the separate regulatory issues, and equally so that the firmware would not support this.  It might be helpful to state what is probably obvious: that I know more about hardware programming than about hardware assembly.

Thank you!

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PriyaM_16
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I am afraid you can not use the chip for frequencies other than 2.4G and 5G. You can refer the WLAN Radio Subsystem in the 43438 datasheet. It says that the CYW43438 includes an integrated WLAN RF transceiver that has been optimized for use in 2.4 GHz Wireless LAN systems. It is designed to provide low power, low cost, and robust communications for applications operating in the globally available 2.4 GHz unlicensed ISM band. The transmit and receive sections include all *on-chip filtering*, mixing, and gain control functions. The Radio functional block diagram is: pastedImage_0.png

Hence it is clear that filtering is in hardware inside the chip.
There are some parameters in the nvram file(specific to platform) regarding the kind of filters used. So part of filtering is also controlled by software.

CYW43438 supports only 2.4Ghz so it can not be used for 5Ghz in any case. I hope this clears your query.

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