Principal architect, designer, and developer for a software defined radio implementing the full Digital Data Link (DDL) communications protocol including security related TRANSEC and COMSEC extensions. Two embedded system firmware (red and black processors) were developed as 60K lines of C++/C/POSIX code using the open-source Zephyr RTOS. DDL is an IP based, small, lightweight, digital network protocol enabling enhanced command and control of a mesh network of airborne and ground assets. The firmware included an extensive interface for XML based configuration, and an extensive Shell interface (serial or Telnet) for radio status and control.Created and implemented a network emulation environment on a standard Linux platform using common Linux device drivers and scripting to enable SDR development in the absence of a target RISCV based embedded hardware. Network emulation supported various configurations: centralized (single workstation for multiple radios), distributed (one workstation per radio), as well as distributed with RF communications using commodity RF hardware for the over the air interface.

I implemented a framework and custom Linux scripting using EMANE for integrating, testing, and analysis of Delay Tolerant Networking (DTN) technologies from Ratheon BBN technologies as a function of various network topologies and path losses. This involved porting BBN applications written for a single instance embedded platform into a multi-instance EMANE/Linux Container environment with a shared file system and integration with our EMANE real-time spectrum viewer. Automated EMANE event scripting was used to dynamically change network node path losses to evaluate and characterize DTN behaviors. The EMANE stack was modified to drive our Robocom EMANE spectrum waterfall viewer application.

http://www.robocomtech.com/emane-wnw-dsa-network-emulation/The Extended Mobile Ad-hoc Network Emulator (EMANE) real-time network emulation framework provides real time network emulation of complex communication devices and custom radio waveforms.I implemented and developed a real-time network emulation framework for analyzing and testing the performance of a multi-node network using the JTRS Wideband Networking Waveform (WNW) based radio waveform. Baseline testing of the WNW performance was augmented by testing with the additions of digital spectrum access (DSA) capabilities to the DSA-enabled WNW waveform.This implementation required the development of thousands of lines or Linux bash shell scripts to orchestrate and control the full network emulation environment based on Linux Containers for virtualization, including EMANE software components, custom WNW software components, and custom developments to support DSA enabled operation.The EMANE network emulation modules (NEM) protocol stack supports customization through the development of custom “shim” layers that exist as part of the executing NEM software stack. A custom shim layer is inserted between component layers in an NEM layer stack without requiring those components to have knowledge of its presence. Custom MAC Layer and PHY Layer shims were required to support DSA integration into the baseline WNW network stack.The PHY Layer shim was responsible for adding and removing a 1024 FFT power spectral density (PSD) signature for the WNW waveform. The MAC Layer shim was responsible for intercepting messages between the EMANE application space and a custom EMANE MAC Layer model, deserializing the messages using Google Protobuf technology, and forwarding the content to the front end of a detector application.All custom software was written in C++ compatible with the EMANE framework, or Linux bash shell scripting.Refer to http://www.robocomtech.com/emane-wnw-dsa-network-emulation/ for more information.

http://www.robocomtech.com/emane-viewer/The Extendable Mobile Ad-hoc Network Emulator (EMANE) is a next-generation framework for real-time modeling of mobile network systems. EMANE is missing a real-time spectrum and waterfall viewer for displaying real time information important to the design and development of communications systems.I created a standalone real-time spectrum and waterfall view application for use within the EMANE network emulation environment. This application monitors and visually decodes the network packets on the EMANE over-the-air control bus.This application represents the only known real-time spectrum analyzer with waterfall heatmap tool for the EMANE network environment. It greatly enhances the usability of the EMANE framework which is currently limited in visualization capabilities to viewing text based log file content, tabular text content, and a standalone visual node positioning application.This application was written in C++ and uses the Qt toolkit to provide cross platform support.Refer to the following URL for more information on this application:http://www.robocomtech.com/emane-viewer/

http://www.robocomtech.com/emane-jammer/EMANE is an industry leading network emulation framework for real-time design and analysis of networking systems. The addition of jamming capability is essential to analyzing and testing frequency agile systems and anti-jamming technologies. I created a custom jammer implemented as an EMANE shim to provide multi-mode jamming capabilities into the EMANE network emulation environment implemented as a fully functional EMANE Network Emulation Network Emulation Module (NEM). The jammer shim exists as part for of the EMANE NEM stack and executes within a separate IP stack facilitated using Linux container technology (LXC). The jammer “shim” is configured for various operating modes to match common jammer types as follows:1. Fixed frequency (CW tone) at a configured center frequency and bandwidth.2. Sweep frequency (sweep through tones) between a start and stop frequency with sweep frequency step interval and sweep rate.3. Hop-set frequencies (stepped tones) with sweep rate and optional random ordering.The jammer shim was written in C++ and adheres to the EMANE framework requirements of an EMANE shim.Refer to the following URL for more information on this application:http://www.robocomtech.com/emane-jammer/

http://www.robocomtech.com/projects/nv/RoboComNV: author of a .NET/Windows client tool in C# that provides network operators and analysts the capability to monitor the performance and status of a wireless network system. This application displays content of data originating from a data source over a network connection. Results may be monitored in real-time streaming or playback mode from previously recorded network activities. The tool facilitates presentation of network performance related to node connectivity, network connectivity, traffic throughput and latency in a quickly comprehended and easily configured visual interface.

http://www.robocomtech.com/projects/ev/RoboComEV: author of a C++ based set of classes that are used to instrument a multithreaded application to record precise real time signal timing and trace information for visualization and analysis. These class libraries provide “Lock-Free” and “Wait-Free” concurrent access to signal trace storage memory from multiple threads to avoid locking issues in multithreaded programming (such a priority inversions) allowing application code to be instrumented without changing its behavior or timing. This analysis tool is used to perform debugging on C++ application code providing C++ developers the features associated with VHDL/EDA/FPGA development following the Verilog or VHDL simulation model of post-mortem interactive visualization following data acquisition to memory storage and the generation of dumpfiles. This class library generates dumpfiles in the Value Change Dump (VCD) format, an industry standard file format generated by most Verilog simulators.

http://www.robocomtech.com/maritime-radio-sbir-phase-2/SBIR Phase 2 Radio Software: Senior software engineer, architect, and developer for an R&D effort to create a low latency high throughput software defined radio (SDR) in C++/Qt code as a Linux daemon. The radio software executes on a network of Xilinx ZC706 and Raspberry Pi 3 multicore ARM based hardware platforms operating under embedded Linux. The software implements smart bridge/firewall technology which limits Ethernet Layer 2 packets transmitted over the RF interface from the wired interface to only packets destined for known host devices passively learned from the network, packets necessary for network discovery and management, or packets filtered by Ethernet frame type. The software stack provides SNMP agent support with compatibility to a legacy radio and configuration persistence to XML formatted files. The technology includes CPU pinning and real time thread priorities to obtain closer to real time performance on a generalized embedded Linux operating system distribution which provides support for user data rates up to 100 Mbps. The headless daemon provides a full featured and mature web interface developed for “mobility first” using the popular Twitter Bootstrap web framework which operates as an integrated web server. The radio software provides standard Linux logging with integral log rotation and user settable log levels. Advanced logging is provided with highly detailed microsecond precision signal timing (similar to a logic analyzer capture) by way of Value Change Dump (VCD) generated output with web settable signal capture filters. The application includes a fully integrated FTP/FTPS client to allow for importing and exporting dynamic configuration and log files. Secured interfaces include support for the HTTPS, FTPS, and the SNMPv3 protocols. Distribution, configuration, and updates of the software components to various hardware platforms are by way of a developed Debian (.deb) package.

http://www.robocomtech.com/inet-link-manager/iNET Link Manager: Senior software engineer and principle architect and software developer (95% of LOC) for the iNET Link Manager as 770K lines of C++/Qt code. The iNET Link Manager provides real time highly reliable control of a distributed radio network providing centralized shared channel TDMA access for the next generation of military test range networked communications. It executes as a Linux daemon on a Red Hat Linux platform. It features a secure Qt based HTTP(S) 1.1 web server and SNMPv3 agent for external control and monitoring, precise time synchronization via Precision Time Protocol (PTP) software, soft configuration via FTPS client loading of XML configuration from an external FTPS server, and built in diagnostics including generation of real time signal timing via Value Change Dump (VCD) formatted output and standard Linux log files with internal rotation. The iNET Link Manager daemon features lock free programming to avoid common errors associated with locking in multithreaded programming (priority inversions, deadlocks, etc.), and takes advantage of parallel processing on multi-processor and multi-core processors platforms via CPU isolation and CPU thread pinning (i.e. CPU shielding). The Link Manager includes a built in Qt based web server providing web content designed using the responsive web design (RWD) approach (using Bootstrap) which supports a wide range of devices from desktop computer monitors to mobile phones. I created Red Hat Package Manager (RPM) files to provide proper Linux platform distribution, installation, and configuration for various software modules. The TDMA algorithm used by the iNET Link Manager was developed and verified using OPNET modeling and simulation tools.

http://www.robocomtech.com/projects/rs/iNET Radio Emulator: Developed a real time radio network emulation cross platform GUI test application in Qt/C++ to emulate the network interface messaging and timing of RF transceivers for execution on a network of Raspberry Pi hardware platforms using Ubuntu or Linux desktops using CentOS/RHEL. Contents for the various generated messages come from loaded spreadsheet files which define message content and repeat patterns to allow for soft coding different test scenarios and conditions. The radio simulator generates real time signal timing tracing via Value Change Dump (VCD) for recording and analysis of precise signal timing.

RDMS3 Front Panel Controller: Created a Telnet Server and Network Agent in C#/.NET/Mono for the Arch Linux embedded Linux platform. The Network Agent is responsible for beaconing messages over the network of the current radio’s status, listening to all other radios on the network and accumulating all network settings, and for the generation of a custom packed binary file that is requested by the web site periodically via AJAX calls to provide the web user a flicker free real time presentation/view of the telemetry radio network.

RDMS2 Control Application: Diagnosed and reworked a multiple man year developed Windows based C# fat client .NET based application used to configure, control, and monitor a telemetry receiver network to provide resiliency to Ethernet network defects (duplicate, dropped, and delayed packets).

http://www.robocomtech.com/projects/sc/RDMS3 Web Interface: Senior software engineer, principle architect, and co-author of an embedded web interface for a telemetry receiver as web backend Python code and client side 3K lines of Javascript. This embedded Arch Linux based web interface providing real time streaming of RF receiver status as eye pattern and power spectral density plots (6 concurrent plots at 10 FPS), configuration, and control for a high performance aeronautical telemetry receiver. This thin client interface replaces the functionality of a previous fat client based application. It is implemented based on the Django/Python/SQLite based framework and uses HTML5, AJAX PUTS & GETS, CSS, Bootstrap, jQuery, browser local storage, and JavaScript technologies. The Django based web site uses the Model–view–controller (MVC) software architectural pattern and runs as a FastCGI application to a lighttpd embedded web server. I created for this embedded site a page lockout scheme to ensure integrity of changes from multiple concurrent web users, a network page displaying real time information for all RDMS3 radios found in the network, loading and saving of user defined preset configurations to the current radio configuration, importing and exporting of radio configuration to/from external JSON formatted files, client side input validation, and the client side Javascript responsible for requesting and rendering visual content including real-time graphics with text overlays and bargraph displays. The web site interfaces with a Front Panel Controller C#/.NET/Mono based application via SQLite database tables, database triggers, and custom binary files including images with appended metadata, and radio network status as a packed binary file.

In telecommunication, LTE is a standard for high-speed wireless communication for mobile phones and data terminals. Carrier aggregation (CA) is used in LTE-Advanced in order to increase the bandwidth, and thereby increase the bitrate, and is used in both Frequency Division Duplex (FDD ) and Time Division Duplex (TDD) modes. 3GPP is the telecommunications standards organization for LTE development.I am currently working with a corporate partner on a high-performance air-to-ground network based on the LTE standard. This network provides carrier aggregation to an LTE airborne deployment using external packet aggregation and custom signal processing at the OSI physical layer to extend network range. This design provides increased data bandwidth and allows for uplink/downlink CA channel combinations which currently exceed the 3GPP specifications which specifies a maximum configuration of 3 downlinks from the eNB to the handset user equipment (UE), and 2 uplinks from the UE to the eNB. This solution uses four 1.4 MHz inter-band non-contiguous carriers in a 4 uplink/4 downlink configuration with each channel operating in SISO mode.The solution required the development of a custom LTE aggregator network device at 225K lines of C++/Qt code to provide access to the LTE network from both the ground & airborne sides of the LTE network to external host devices for user data. The LTE Aggregator application executes as a Linux daemon on a 64-bit Ubuntu multi-core Intel desktop platform on an external platform, but can also execute on either the UE or EPC platforms. It is responsible for:* providing a gateway interface to host facing devices,* smart bridging of host traffic across the LTE network using tunneling/ip encapsulation,* best channel selection adaptive scheduling based on channel link metrics or non-adaptive round robin scheduling, * OSI Network Layer 2 to 3 packet conversions, and* Multipath packet reordering.

Sentinel Blackbelt Pro: created a multithreaded application for embedded Debian Linux as 3K lines of C++ source code which provides the touch screen user interface for CTS’s latest multi-test, multi-port, multi-channel leak test instrument. This application was written using Qt/C++ and communicates with a real time processor via UDP in a dual processor configuration. The user interface provides the characteristics of modern cell phone fluid interfaces including touch screen control, swipe navigation, rich multiline list controls, embedded keyboards, pop up context menus, icon based selection screens, animated scene transitions, over scroll animations, international language support, and kinetic scrolling. Implemented real time 2D line graph plotting which utilizes a max-min data decimation algorithm to handle plotting unlimited data.

Wideband Networking Waveform (WNW) Viewer: Created as 5K lines of C# code a standalone .NET based network visualization application for understanding and visually analyzing highly mobile wireless networking algorithms, protocols, issues, interference, and ad hoc routing. This application communicates with an OPNET network simulator over the network adding real time visualization capabilities to OPNET. It enables two-dimensional displays of OPNET network simulations that incorporate node relationships, node connectivity, and performance statistics in the form of line graphs. The application provides simulation results storage and playback to allow for viewing simulation results without OPNET.

MEADS Radio: Researched, designed, developed, and documented all Point to Point Over Ethernet (PPPoE) specific threads, interfaces, and routines to support a real time multithreaded radio which executes under embedded MontaVista Linux on a PowerPC platform. Developed Cisco router configurations to support testing of multiple radios using PPPoE with credit flow.MEADS Radio: Member of a design team which created an embedded Linux application which implements a dynamic TDMA scheduler based on obtaining multiple Cisco routers’ unicast and multicast router tables content via SNMP, and allocating bandwidth by analysis of the network node connectivity.MEADS Radio Emulator: Developed a real time multithreaded application for Red Hat Fedora Linux emulating Mobile Ad Hoc Network (MANET) radios and providing PPPoE connections to Cisco routers for router-to-radio communications, PPP Data Link Layer bridging for peer router-to-router communications and fully implementing credit flow and quality of service (QoS) extensions to PPPoE. This application generates event notifications via SNMP and allows for customizing radio parameters such as neighbor lists, packet latencies, packet drops and bandwidth allocations per link.

Custom Microsoft Office Add-In: Designed and developed a version neutral, application neutral, lightweight Microsoft Office for Windows add-in in C++/ATL/COM that allows a user to send very large documents from within Office applications to the cloud based application server.

Lexmart Custom Test Stand: Designed and developed a human machine interface (HMI) application in National Instrument’s LabVIEW graphical programming environment to implement a customized multi-station automated leak test system for leak testing printer cartridges during manufacturing test. The HMI operates on a touch screen industrial computer and communicates with a PLC to control tooling.Custom Leak Test Stand: Developed the middleware to allow a custom leak test stand to display user guides in PowerPoint as controlled by a PLC via a DDE connection to Rockwell Automation’s RSLinx communications server. C28: Integrated an embedded systems USB host stack into CTS’s C28 Leak Test Instrument based on Freescale Coldfire processors communicating over a CAN network.Leak Test Instrument Source Code Generation Tool: Designed and developed a custom software developer productivity tool in Microsoft Access and extensive Visual Basic for Applications (VBA) programming that automatically generates source code files in embedded ‘C’ and includes support for multiple foreign languages with the ability to import/export UTF-8/Unicode content as language translation files with a built-in XML Localization Interchange File Format (XLIFF) parser.

Sentinel I-24: Developed firmware using Metrowerks-AT MQX RTOS and networked Motorola Cold Fire 5282 boards communicating over CAN bus. Responsible for flash storage device drivers, test results statistics, counters, system backup/restore, advanced diagnostic logging, USB storage, electronic regulator support, environmental drift correction, configuration, encryption, and improvements to system performance and reliability.Sentinel I-24: Generated a reliable communications stack in C#, refactored, profiled, enhanced, and added features and 3rd party controls to a performance critical, multithreaded .NET WinForms HMI application. Modified the GUI of the .NET based application using a plug-in based architecture to look and behave like MS Office. Developed a PC based LabView compatible DLL in C++ used to communicate with instruments from a NI LabView test and analysis application. Developed DLLs in C++ to successfully integrate a LabView based control application with an I24 and engine control module using mail slots and global shared memory for Inter-Process Communications (IPC).

XM-7 Spider: Developed embedded software for secure, frequency hopping, spread spectrum wireless transceiver for next generation networked intelligent munitions which required firmware for dual processors: 32-bit TI 5510 DSP and 16-bit TI MSP430 RISC low power mixed signal processor. The 30 thousand lines of ‘C’ language code followed object oriented constructs and utilized the TI DSP BIOS RTOS while following the IEEE 802.11 wireless specification. XM-7 Spider: Collaborated on system requirements and architecture, hardware interfaces and protocols, device drivers, development of application level processes (duty-cycled low powered sleep mode, over the air programming, built in self test, establishing a global clock) and the following ISO/OSI network layers: Physical (including all hardware and interface device drivers: EHPI, SPI, RS-232, Flash), Logical Link Control, and Medium Access Control (using Carrier Sense Multiple Access with Collision Avoidance). XM-7 Spider Test: Developed a custom application in C++/Windows to analyze transceiver network behavior, performance, timing and adherence to the system specifications, and composes any of the hundreds of system messages from the embedded transceiver with unique parameters proving decoded send, receive and binary panes. Transceiver Configuration Tool: Designed, implemented and documented a specialized OLE/ActiveX control in C++ for Windows used by system integrators to configure commercial wireless ad hoc IP router which uses UDP to detect the radio's IP address, and thereafter TCP/IP to set the radio's final IP address and operational parameters.

FN2LV: Developed a highly reliable custom image conversion applications for converting/importing/migrating electronic medical records stored on legacy FileNET optical servers into the LanVision Electronic Medical Record (EMR) system which operates in a hospital environment 24x7.Created several enterprise applications as part of the LanVision Professional Services department and as part of the LanVision EMR application development team.Developed LanVision's OmniVision image-enabling application and underlying image components. This application provides physicians and clinicians access to the entire electronic medical record and is used to image enable health information service applications like Oacis using OmniVision’s OLE automation interfaces.

Custom Medical Procedure and Billing Application: Designed and developed a complete multi-user database entry and reporting solution in Microsoft Access for managing medical procedures and associated CPT codes for billing and insurance. Created a custom application in C++ to convert legacy medical records in Excel format into normalized database format for importing into Access databases.

ColdServ application: Responsible for modifying, diagnosis, field support, and enhancing IDX’s ColdServ application. ColdServ is a listener agent that obtains electronic medical records from a mainframe over a TCP/IP network connection for printing and storing to disk (COLD). The EMR originates on a Tandem mainframe as part of the IDX LastWord Enterprise Clinical System.

Modified machine control man-machine interface (MMI) software to support advanced OLE drag and drop between OLE servers. Principal system architect for the design and development of a wireless pager gateway system in C++/MFC utilized in medical enterprises for automated consult referrals. This system is a listener agent/application that obtains medical referral information from a network accessible computer over a TCP/IP link, and implemented and utilized the Telelocator Alphanumeric Protocol (TAP) for sending short messages via a land-line modem to a provider of pager and/or SMS services, for onward transmission to pagers and mobile phones.Designed and developed an OLE compliant server side wireless gateway.

IBM Mainframe access ODBC Driver: Responsible for the commercial release of an industry leading client/server ODBC driver/middleware tool that allows users to access and manipulate IBM host data using any ODBC compatible Windows application. This driver supports IBM’s Distributed Relational Database Architecture (DRDA) protocols. Enhanced product performance and compatibility with leading commercial applications, developed multithreaded test applications for driver verification and bench marking, diagnosed and fixed numerous customer deployment field problems and created installation applications (32 and 16 bit releases).

EMR Software: Responsible for the design, coding, testing, implementation, maintenance, bug corrections and performance enhancements of various component modules of a high-end enterprise wide client/server based medical document imaging system. Modified client software modules including standalone servers, executables, and support DLLs to support FileNET and LaserData Optical servers. Developed a C++/MFC/embedded SQL based quality assurance application to verifying the integrity of all images stored on magnetic or optical storage for EMRs. Developed a general-purpose text/image viewer toolset/suite as embeddable OLE components or OLE servers for use in LanVision applications for viewing medical documents including annotation support.

Responsible for program management, system engineering and lead design engineering on several programs for the design of low power communications systems and automatic test software. Designed products using a range of hardware (with emphasis on Motorola/Intel microprocessors) and software/firmware languages (with emphasis on C++, C, and assembly).Created secure voice based applications utilizing object-oriented application frameworks featuring real-time full duplex operation, audio compression and decompression and an implementation of the XModem communications protocol. Developed firmware for a hand held programmer that included a custom real time interrupt driven non-preemptive multitasking operating system, software partitioning into separately executing tasks, semaphores, inter-process communications, internal diagnostics and automatic testing support.Reverse engineered and modified the assembly language firmware for the TRS-80 Model 100, one of the first notebook-style computers, repurposing this notebook computer to act as a terminal.

Subsystem leader for highly reliable avionics used on an aerospace satellite communications system deployed using the Space Shuttle. Responsible for the digital hardware design of flight hardware, timing and worst case analysis, development of automatic test equipment software for a custom test rack, and hands-on diagnostics and troubleshooting of equipment failures during formal spaceborne Qualification and Environmental Testing.