Senior Software Specialist

AUG 2004 – APR 2009

Role

Accomplishments

  • Re-engineered core channel card product for important specialized application, with minimal support from overseas division.
  • Type approved layer 2&3 satellite terminal with INMARSAT in absence of key test equipment components.
  • Reverse engineered legacy components to run on more modern platforms.
  • Ported proprietary PPPoE stack to alternate platform.
  • Introduced SNMP and developed MIBs for core product.
  • Re-architected Aeronautical MCDU (Multifunction Control Display Unit) user interface software to facilitate rapid menu development and scalability.
  • Adapted satellite control processor subsystem to accommodate new product requirements
  • Assisted in RFP work 

Re-engineered Core Channel Card Product

Required to implement a “retro” data communications protocol on a new generation target. Integrated it onto a MIPS AU1100 platform with ATMEL MEGA/1890 RF Controller. RF controller required many modifications to compensate for new antenna, non-oven controlled reference oscillator, power amplifier, temperature compensation, GPS/Compass control, DAC and ADC configurations. Many new device drivers written for both platforms.

Challenges

No geo-proximate support for firmware. Support in the UK allowed a 3-4 hr daily window. Tight budget for UK resources . Received congratulatory letter for accomplishing the impossible.

Type Approved layers 2 & 3

Performed acceptance of a satellite terminal required Type Approval for layers 2 & 3. Learned and developed new test procedures and to use several new pieces of test equipment.

Challenges:

No pre-existing Type Approval equipment available. Special arrangements with INMARSAT and test equipment manufacturers were setup. Test equipment and their attendant HW and SW and scripts needed to be adapted. Identified and coordinated the adaptations.

INMARSAT satellite coverage in constant flux due to the bringing on line of new satellites and services. Learned to identify source of inconsistencies, tier partner responsible and adapt testing to compensate.

Reverse Engineered Legacy Components

Given ‘C’ code for old data communications protocol and ported it to C++ and integrated it onto a MIPS AU1100 platform with ATMEL MEGA/1890 RF Controller.

Challenges:

Integration onto modern platform required device driver, call setup and AT telephony modem protocol changes as well as introduction of PPPoE over the satellite link.
Ported PPPoE Stack
A satellite terminal product required that a PPPoE stack be installed on the MIPS AU1100 (main satellite protocol (GAN/BGAN) control card) to perform PPPoE over a satellite link. A proprietary PPPoE stack existed on another platform whose main function was to control communications between the GAN/BGAN card and peripherals that existed at the satellite terminal site. This stack was ported.

Challenges

The RTOS on both systems was different (MQX on one and Nucleus on the other). Required modification of COTS Nucleus RTOS device drivers to siphon off PPPoE packets.

The Discovery and LCP packets had to bridge more peers to the ISP than in the original version so the original stack needed adjustments. Latencies from the added peers compounded by the satellite link delay and the slow transmission rate offered by the service created “timeout” issues not handled by the ISP’s stack. Designed feature to spoof the ISP into resetting its timers.
SNMP
When first joining EMS, SNMP was to be installed on the Data Control Card to perform System management for their satellite terminals. After a week of discovery of their requirement and platform it was declared to be impossible to accomplish the task in the anticipated 2 week time line. Had opportunity to install the MIBs, utilizing COTS MQX SNMP stack and a provided design, at a later date.

Aeronautical MCDU

Worked to Re-architect Aeronautical MCDU (Multifunction Control Display Unit) user interface software to facilitate rapid menu development and scalability. This included ARINC device driver modifications. Work was performed in ‘C’ on a TMS320C30 target and required Makefile development under an MKS development system. Rework was necessitated by “legacy” coding and hardware, to extend life of platform.

Challenges

Requirements were extremely vague due to contractual circumstances. Ongoing development of the requirement specification was also performed.
Legacy software base was resource starved. Made appropriate coding decisions to mitigate problems.

Adapt Satellite Control Processor Subsystem

Adapted code to accommodate new
• Call Control interfaces and protocols (PRT/Classic AERO and GAN).
• BITE configuration
• Configuration management
• Power Control

Challenges

Legacy code with virtually no documentation. Relied mainly on reverse engineering techniques and observation.

Management changes.

Tight deadlines.

RFP Work

Performed risk analysis and developed contingency strategies to assist EMS and customers in decision making, to go forward with new products and features.

About EMS SATCOM

EMS SATCOM: provides its customers with more efficient mobile communications resources when and where they need them. With its alliances and partners, the company has excelled at delivering products that provide critical resources to users in the air, on land and at sea. The company is a wholly owned division of Atlanta-based EMS Technologies Inc. (NASDAQ:ELMG), and is a pioneer in the development of satellite-based communications equipment. Its products and services enable users with real-time mobile broadband voice, data and videoconferencing capabilities virtually anywhere in the world. Located in Ottawa, Canada, EMS SATCOM employs over 230 people and has sales offices in Washington, D.C. and Monterrey, Mexico—as well as a development lab in Tewkesbury, U.K.

The principal focus of EMS SATCOM is business and military aviation, but it has leveraged its expertise in satellite-based communications equipment to address the land mobile and maritime segments as well. Since 1978, the company has also been deeply involved in the Search and Rescue (SAR) field developing both equipment and software for the management of SAR operations that has saved more than 17,000 lives.

Allied with Inmarsat, the world leader in mobile satellite communications, the company’s products include terminals, antennas and radomes, and cabin network equipment. Its customers are front-runners in a diverse range of industry segments.

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