with 802.11b only, It's limited to 11 Mbps. You want a 802.11b/g or an 802.11a (or a/g).
802.11a and 802.11g have basically the same throughput (basic set-up is 54 Mbps, some setups are faster by reducing packet headers). The advantage of 802.11a is there are few phones and routers using that frequency (5GHz) so you have less interferance. The disadvantages are shorter range (25-75 feet versus 100-150 feet) and higher cost.