Senior RF / Phased Array Systems Engineer

About the Company

Our client is a seed-stage defense tech startup building a new class of distributed sensing systems enabled by modern RF and communications infrastructure.

Traditional sensing systems are often expensive, centralized, and increasingly vulnerable in modern operating environments. Our client is taking a different approach, developing systems designed to be more scalable, resilient, and deployable across a wide range of conditions.

Recent advances in satellite and communications infrastructure have created a meaningful shift in the availability of RF signals globally. Our client is leveraging these conditions to enable sensing capabilities that were previously impractical to deploy at scale.

The long-term vision is a low-cost, distributed sensing layer that can be deployed broadly rather than relying on a small number of high-cost systems. This enables more persistent awareness, greater resilience, and new capabilities across defense and commercial applications.

They are currently in a rapid build phase, working toward an early system demonstration with strong interest and backing from government and commercial stakeholders.

This is a unique opportunity to join at the ground floor of a high-caliber founding team composed of former SpaceX and Capella engineers, building a system with real traction.

This is a direct hire, permanent placement position for a client of AdAstra Talent Advisors. This position is based in San Francisco, CA. More company details will be shared during an initial call.

About the Role

Our client is seeking an RF-first engineer to own the design and development of phased array antenna hardware for a novel sensing system.

This role will serve as the primary owner of antenna and RF hardware, with responsibility spanning early prototype validation through custom antenna design.

This is a ground-floor role focused on 0→1 system development, where you will define the RF and antenna architecture from first principles rather than inheriting an existing design.

This is not a narrow component role, but a system-level ownership position with broad responsibility across the antenna and RF domain.

You will collaborate closely with radar, DSP, and software teams to translate system requirements into physical hardware. The team operates with a strong bias toward speed and execution and is actively working toward an early system demonstration that this role will directly support.

Responsibilities

• Own the design and development of phased array antenna hardware from prototype through productization

• Define RF and antenna architecture, including array geometry, element design, and system integration

• Lead hands-on bring-up, measurement, debugging, and experimental validation of RF systems

• Lead or contribute to early prototype efforts using commercial off-the-shelf hardware

• Drive system-level trade studies across performance, cost, power, and scalability

• Work closely with radar, DSP, and software teams to ensure antenna and RF hardware are tightly integrated into overall system performance

• Drive the transition from prototype hardware to custom antenna design and scalable deployment

Requirements

• 5 years of relevant experience in RF systems, antenna design, or multi-element sensing systems

• BS, MS, or PhD in Electrical Engineering or related field, or equivalent industry experience

• Hands-on experience with phased array antenna systems beyond a single subcomponent

• Demonstrated ownership of complex RF or antenna systems from concept through validation or deployment

• Solid understanding of RF signal chains and system-level tradeoffs

• Strong experience designing and developing RF hardware, including hands-on bring-up, debugging, and validation

• Ability to reason from first principles and make architectural tradeoffs

• Ability to operate effectively in fast-paced, low-structure environments

• Experience working in complex RF environments (e.g., satellite communications, radar, or similar systems)

• Experience using or working with EM simulation tools (HFSS, CST, or similar) as part of RF or antenna system design

Logistical Requirements

• This position is on-site in San Francisco, CA 

ITAR Requirement

• To conform to U.S. Government space technology export regulations, applicant must be a U.S. citizen, lawful permanent resident of the U.S., protected individual as defined by ITAR (22 CFR §120.15), or eligible to obtain the required authorizations from the U.S. Department of State. Learn more about the ITAR here. 
  
  

Cash compensation of $200,000 – $280,000 per year plus meaningful early-stage ownership grant. Compensation is determined by role, level, location, and alignment with market data. Individual pay may vary based on job-related skills, education, experience, technical capabilities, and internal equity.

Equal Opportunity

Our client is an equal opportunity employer. They evaluate qualified applicants without regard to race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.

About AdAstra                                                                                                                         

AdAstra Talent Advisors is a headhunting and talent advising firm focused on the Climate, Space, and Defense sectors of Hard Tech. We specialize in pairing highly technical and executive talent with some of the world’s leading Hard Tech startups.

At AdAstra, we catalyze the innovations that future generations depend on by placing the right people in the right seats. Our dedicated work enables inconceivable technology from Earth, to the stars. And it’s all because of trailblazing talent like you - those driven to do what’s never been done before. 

We care about long term relationships with both candidates and companies. Even if the role we initially discuss isn’t a perfect fit, it’s likely we’ll have something relevant to share with you in the future. 

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