Senior Systems Engineer, Wireless

In a Systems Engineering role at Tarana you will be working on all aspects of our next-generation Fixed Wireless Access products (ngFWA).  We develop both the base stations, CPE, and cloud management tools for a complete solution to FWA providers.  System Engineers are involved at the individual device level (base station or CPE) but also the link level, sector/cell level, and network level.  This spans from low-level front-end RF and calibration through PHY and MAC layer, switches/network interface, and sector and network design and optimization.  Tasks range from simulation and analysis of new features/products to hands-on testing and bring-up of new hardware and to analyzing and conducting experiments on real customer deployed systems and whole sectors and networks.  We are a fast-paced company with many opportunities to learn, grow, and have a big impact.

A successful candidate will be able to:

• Play a significant role in developing new features
  • Identify areas for system performance improvement in line with business and customer use cases and product road maps
  • Document proposed feature and support expected performance or justification for feature with analysis, simulation, and lab/field test data
  • Present feature to team/developers and iterate on architecture/algorithm based on developer feedback and implementation/platform limitations
  • Provide simulation results/test vectors for developers to use for implementation verification
  • Design tests and procedures and communicate expected results to testers
  • Work with field support team to follow up with design implementation once deployed to verify correct performance in the real world
• Design tests to verify feature/sub-system performance
  • Identify requirements and comprehensive corner cases that need to be verified
  • Manually run systems tests to prototype procedures, demonstrate expected results, and provide detailed procedure or test techniques and expected results to the automation team
• Support debugging and root cause analysis efforts of performance shortfalls
  • Help with test data analysis and manual testing of systems in lab or field to diagnose sources of bugs
  • As an expert in the system (or at least a representative of the systems team), provide detailed instructions/ideas for support and test groups to focus on in the debug efforts
  • Run existing or create new simulations to help in the debug effort
  • Work with developers during software release/integration to test proposed fixes and provide feedback and detailed ‘steps to reproduce a bug’
  • Be able to take system-level behavior and identify possible root causes or subsystems that could be at fault.  Suggest tests to isolate which piece of the system may be the issue.  Manually run tests on the system to do the above.
  • Be willing to ‘own’ a problem, even if you aren’t an expert in that particular piece.  Proactively search out experts and necessary knowledge to support the effort. 
• Develop ‘hands on’ capability to run systems in the lab and characterize different aspects.  Be able to quickly (without waiting for automated test development) put a new release/feature through its paces and assess if there are any bugs/shortcomings, etc.  This includes
  • Traffic/latency tests
  • Range vs Rate and system gain
  • Calibration aspects.  Transmit power and distortion.  Noise figure.
  • Interference rejection
  • Scheduling and multi-user performance 
• Collaborate with the RF team to analyze hardware performance results to ensure that system specifications are met across all supported hardware configurations, and fold hardware characteristics into software.
• Support manufacturing tests
  • Debug system and board acceptance test procedures/scripts
  • Identify appropriate thresholds for tests
  • Support debugging of manufacturing yield issues

Required Skills & Experience:

• M.S. or Ph.D. in Electrical Engineering 
• 5-12 years of industry experience developing wireless technologies
• Have theoretical and practical knowledge in all aspects of an OFDM-based wireless communications system with detailed knowledge in several of the following:
  • RF (modulation, rf impairments and mitigation, calibration, antenna gain, link budgets)
  • PHY (coding schemes, ACM/MCS, ARQ/HARQ, error rates, equalization, synchronization)
  • MAC (ethernet, packet formats, PER vs BLER/TBER vs packet size, scheduling algorithms)
  • MIMO processing (beamforming, channel models, channel capacity)
  • Transport layer (TCP/BBR/QUIC/UDP/streaming protocols)
  • Ethernet Switch (BDP and buffer size selection, bottleneck links/BW, standing queues/bufferbloat/AQM)
  • Network optimization (cell planning, sector loading, sector capacity analysis)
• Candidate should be able/willing to do a deep dive into any one of the above system components to become a ‘resident expert’ even if they haven’t had a strong focus on it in the past
  • Emphasis is on understanding the function of each piece, how to test, and what expected/required performance should be
• Ability to develop / maintain Matlab simulation of system components at various levels
  • Be able to generate small Matlab simulations quickly from scratch to investigate specific issues/concepts that may not be covered by an existing simulator
  • Be able to work to run/modify existing simulation frameworks. Have enough general understanding of communication system components/concepts to pick up a simulation of any aspect and make progress (even if not an expert in the particular domain)
  • Experience with fixed-point modeling a plus
• Be able/willing to become the Systems Engineering point of contact for a given aspect of the system (RF/PHY/MAC, etc).
• Excellent written and verbal communication skills and a go-getter attitude
• Strong foundation in wireless radio receiver/transmitter architecture, sampling theory and signal processing
• Prior experience working on 3GPP or WLAN based products or other OFDM MIMO based wireless products
• Familiarity with lab equipment such as signal generators, spectrum analyzers, power meters, signal analyzers and network analyzers
• Comfortable using Python for development of experiments and regression suites

The salary range for this position is: $130,000 to $175,000

Compensation will be determined based on several factors including, but not limited to: skill set, years of experience and the employee’s geographic location.

Tarana provides competitive benefits to employees in this role including: Medical, dental and vision benefits, 401K match, flexible time off and stock option.