Sr. Satcom Modem Engineer

Welcome to Planet. We believe in using space to help life on Earth. Planet designs, builds, and operates the largest constellation of imaging satellites in history. This constellation delivers an unprecedented dataset of empirical information via a revolutionary cloud-based platform to authoritative figures in commercial, environmental, and humanitarian sectors. We are both a space company and data company all rolled into one. Customers and users across the globe use Planet's data to develop new technologies, drive revenue, power research, and solve our world’s toughest obstacles. As we control every component of hardware design, manufacturing, data processing, and software engineering, our office is a truly inspiring mix of experts from a variety of domains. We have a people-centric approach toward culture and community and we strive to iterate in a way that puts our team members first and prepares our company for growth. Join Planet and be a part of our mission to change the way people see the world. Planet is a global company with employees working remotely world wide and joining us from offices in San Francisco, Washington DC, Germany, Austria, Slovenia, and The Netherlands. About the Role: Planet is developing the next generation of small satellite buses, featuring high-resolution optical imaging payloads, a space-based data center connected by optical inter-satellite links (OISLs), and high-speed RF/Microwave communication links. We continuously iterate on and develop small spacecraft communication systems—including board-level hardware, antennas, and ground station equipment—to achieve record data rates and link performance. Our system utilizes proprietary and industry-standard modems, transceivers across several bands, optical laser communication systems, and a worldwide network of ground stations. We are seeking an experienced Satcom Modem Engineer to develop and mature our next-generation onboard satcom links, ground radios, and antenna systems, pushing the frontiers of satellite communications. You will architect, design, simulate, implement, and validate cutting-edge software-defined Satcom radios. Responsibilities include characterizing the SDR link performance of Planet’s next-generation S through Ka-band and optical terminals, selecting vendors, and managing subcontractors for Satcom solutions. You will facilitate and conduct rigorous testing on space and ground communication subsystems to ensure flight readiness. Success requires close collaboration with RF, EE, Flight SW, systems engineering, missions, and manufacturing teams. The ideal candidate thrives in an agile, fast-paced environment and is comfortable with ambiguity. This is a full-time, hybrid role which will require you to work from our San Francisco office 3 days per week. Impact You'll Own: Develop GnuRadio-based ground modem solutions. Architect, design, and verify space segment software-defined radios and modems. Lead on-orbit performance validation for end-to-end satellite communications systems. Lead RF/MW/Optical Communications system integration and testing. What You Bring: Strong experience with DSP algorithms, digital communication theory, and implementation (including digital modulation, synchronization, error correction, floating-point, and fixed-point design). Experience with Software Defined Radios (SDR), specifically GNU Radio and Linux development tools. Experience defining and measuring radio performance metrics in real time (e.g., SNR, BER, PER, and constellation visualization). Experience with state-of-the-art RF System-on-Chip (SoC) implementations. BS in Electrical/Computer Science or equivalent experience with a focus on digital communicatons. What Makes You Stand Out: MS or Ph.D. in Electrical Engineering with a focus on digital communications. Expertise in Matlab and Simulink for modem design. Experience with SDR platforms and associated signal processing libraries (e.g., GNURadio). Proficiency in Linux, Python, and data analy…