Frequency Hopping would be the most effecient approach. With FH a radio typically uses a 1MHz channel and stays there for approximately 200ms. Because the channel is so small, the FCC allows for higher TX power. In 2.4Ghz the 50mw limit for Spread Spectrum is compared to 500mw for Frequency Hoppers. The system must also change frequencies without repeating the same frequency again until 80% of the channels have been utilized in a sequence. This mitigates interference very effectively. Add something like OFDM and QAM128 and you have a very powerfull system.
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Frequency Hopping would be the most effecient approach. With FH a radio typically uses a 1MHz channel and stays there for approximately 200ms. Because the channel is so small, the FCC allows for higher TX power. In 2.4Ghz the 50mw limit for Spread Spectrum is compared to 500mw for Frequency Hoppers. The system must also change frequencies without repeating the same frequency again until 80% of the channels have been utilized in a sequence. This mitigates interference very effectively. Add something like OFDM and QAM128 and you have a very powerfull system.