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Hi Fmedina:

IEEE 802.11 clause 15 defines DSSS PHY with 1 and 2 Mbps modulations and defines channels to be non-overlapping if center to center channel separation is at least 30 MHz.

IEEE 802.11 clause 18 defines HR/DSSS PHY with 1, 2, 5.5, and 11 Mbps modulations and defines channels to be non-overlapping if center to center channel separation is at least 25 MHz, regardless of modulation.

I wish I could explain why 25 MHz is good for HR/DSSS PHY while 30 MHz is good for DSSS PHY, but I can't.

I can say that HR/DSSS and ERP PHYs interoperate fairly well even when their channels overlap a bit. And there aren't many DSSS PHYs in service in 2006 (I hope).

I hope this helps. Can you put your location in your forum profile? Thanks. /criss