Principal Engineer RAN (Satellite to Cellular Networks) Miami, Florida, United States Position Available In Miami-Dade, Florida

Principal Engineer – RAN (Satellite to Cellular Networks)
at AST SpaceMobile
Miami, Florida, United States AST SpaceMobile and our global partners are building the first and only space-based cellular broadband network to be accessible by standard smartphones. Called SpaceMobile, this ultra-powerful network is being designed to provide connectivity at 4G/5G speeds everywhere on the planet – on land, at sea and in flight.

Summary:

Act as the end-to-end technical authority for the Radio Access Network within AST’s Satellite & Cellular Networks Integration (SCNI) program. This role blends system-level architecture, Layer 1-3 troubleshooting, and deep RF protocol expertise. You’ll lead validation from lab to field, drive performance alignment with Tier 1 operators and other global operators and ensure the radio interface is launch-ready for AST’s direct-to-device satellite service. This role serves as the face of AST for all RAN-related matters—acting as the E2E technical authority across internal teams and external stakeholders, both local and international.

Key Responsibilities:

Architect and own RAN subsystem integration across satellite and terrestrial interfaces
Drive simulations, E2E scenario design, vendor interoperability, and benchmark testing
Execute RF analysis, cell parameter tuning, and interference resolution for multi-vendor RAN
Lead deep-dive debugging across Layer 1 (PHY), Layer 2 (MAC/RLC), and Layer 3 (RRC/S1AP)
Perform log-level analysis using UE tools (QXDM, TEMS, Accuver) and network-side logs
Validate handovers, paging, call flows, and KPIs across satellite beam and terrestrial boundaries
Collaborate with device OEMs, gateway teams, and satellite payload SMEs to align RF interface
Contribute to lab setup, coverage modeling, and automation of testing pipelines

Preferred Background:

15-20+ years of telecom experience with deep technical ownership in RAN, RF, and Layer 3 protocols
VoLTE and VoNR expert with hands-on optimization across NTN to TN (Satellite to Cellular) call flows as per 3GPP Release 17/18
The RAN Principal Engineer must have deep expertise across LTE, 5G NR, VoLTE, and VoNR features, with hands-on experience in performance analysis using tools such as QXDM, Actix, and TEMS— owning the validation cycle end-to-end through to production-grade acceptance.
Must be able to lead deep-dive debugging across Layer 1 (PHY), Layer 2 (MAC/RLC), and Layer 3 (RRC/S1AP).
Proven delivery in Tier-1 operator environments
Strong expertise in physical layer design, Layer 3 decoding, and protocol-level troubleshooting
Experience with 5G SA/NSA, cloud-native architectures, and satellite NTN adaptations
Hands-on with tools: TEMS, QXDM, Accuver, Keysight, Spirent, Anritsu, Wireshark
Vendor management experience

Operator Standards & Tools:

TEO, iPro, Service Assurance, TEMS Investigation, InSite

IRIS, MOSHELL, NEMO, QA

processes

Notable Achievements:

Led commercial rollouts or lab-to-field transitions in Tier-1 networks
Developed architecture or troubleshooting frameworks adopted across OEMs
Filed patents or delivered innovative solutions in RF or Layer 3 domains

Soft Skills:

High accountability and execution under pressure
Cross-functional influence without formal authority
Exceptional documentation, system modeling, and executive communication skills
Independent and result-driven, able to deliver without direct supervision AST SpaceMobile is an Equal Opportunity, at will Employer; employment is governed on the basis of merit, competence and qualifications and will not be influenced in any manner by 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.