I was writing firmware for RX transceivers when Bluetooth was specified. I feel like they wrote the spec with very little input from chip designers and without building prototype hardware.
That's why they chose a GFSK frequency hopper. Which ignored the expected advances in low power spread spectrum radio's. Previously the power requirements for a spread spectrum receiver were way too high, but within a two years of releasing the spec power requirements dropped dramatically. RF chip designers new this was going to happen.
Same time their baseband requirements were almost impossible to meet with a low power budget even in 2003 or so. So you had a crummy GFSK radio, frequency hopper. Married to a fat piggy baseband spec.
What I remember is about two dozen design groups spent a couple of years developing Bluetooth hardware and by 2004 or so exactly three of them succeeded. That's big indictment of the spec. And here 20 years later it still sucks.
That's why they chose a GFSK frequency hopper. Which ignored the expected advances in low power spread spectrum radio's. Previously the power requirements for a spread spectrum receiver were way too high, but within a two years of releasing the spec power requirements dropped dramatically. RF chip designers new this was going to happen.
Same time their baseband requirements were almost impossible to meet with a low power budget even in 2003 or so. So you had a crummy GFSK radio, frequency hopper. Married to a fat piggy baseband spec.
What I remember is about two dozen design groups spent a couple of years developing Bluetooth hardware and by 2004 or so exactly three of them succeeded. That's big indictment of the spec. And here 20 years later it still sucks.