Hasan Rashid

Led the 802.11ac Wave 2 160 MHz chip bring-up for access points by Qualcomm Atheros.

I led the collaboration between multi-geographical teams in China, India, and Taiwan and cross-functional teams, including hardware, protocol, host systems, QA, and product management. I leveraged emulation code for silicon bring-up and directed the team in developing WiFi chip radio configuration and performance algorithms. We delivered a functional chip in four weeks, with the live demo securing key customers' businesses.

This access point chip had dual 80 MHz synthesizers working in tandem to deliver a 160 MHz bandwidth. It also featured multi-user, multiple input, multiple output (MU-MIMO) technology with peak data rates of up to 1.7 gigabits per second.

A customer needed a lower-cost solution to ACMS data. Typical products cost around $100,000, and I was asked to devise a more cost-effective way to access this flight data. There was limited information on the protocol used, only that it is transferred over RS-422 between embedded devices in the electronics bay of the aircraft.

The customer offered access to one of their Boeing 777 cargo planes for development and data gathering. I devised a plan to sniff the data during transmission, decode the protocol live, and then create the software application that would eventually run on our product. The electronics bay of the Boeing 777 was cramped, and only two people could get in. We fired up the engines, and the plane was transmitting while I was hooked into the RS-422 lines, eavesdropping on the data. It took 20 hours inside the avionics bay to decode the complete protocol. I implemented the solution and tested and verified it with a concocted simulation setup of captured data logs. We implemented this in our product, which was one-fifth of the cost of our competitors.

Wi-Fi links are half-duplex between two repeater APs. One of the key limiters in increasing the back-haul link capacity of a wireless ISP is the radio bandwidth. The APs I worked with had two Wi-Fi radios, but only one was used for AP<->AP connections. I analyzed the problem and devised a solution utilizing the existing HW. I customized the Linux bridging module and, in essence, created a full-duplex wireless link between two APs, effectively boosting the physical bandwidth by 90% and usable link capacity by 70%, including the packet overhead.

I directed and coordinated the deployment of this FW upgrade throughout the 8,000-node WISP network, including rural sites. The dramatic increase in link efficiency improved bandwidth availability for the promised speeds to customer CPE.