Lousy throughput with DPAC Airborne WiFi module

Some of the guys at my company are seeing lousy throughput performance
with the DPAC Airborne WiFi module ( WLNB-AN-DP102). It is hooked into
our embedded system with SPI. The rating is for 20MHz SPI frequency,
but we can only get it to talk at 1.5MHz. So that is one problem.

Even worse, when in use with many TCP or UDP packets, the module seems
to buffer data for a long time and then dribble packets out at a
300msec interval rate. The spec says we should be able to sustain
300kbs in one direction and 70kbs in the other... I think we are
getting only a very small fraction of this.

Any ideas on what we should check into or try to do differently?
Anyone else seen this kind of behavior with the DPAC modules? DPAC
Tech's not responsive lately to inquiries. Any insight you smart folks
can lend, we would appreciate! We are open to switching brands if
anyone has seen really good results with another comparable module.
--
Mike

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