Wireless Network Protocol Engineer

About the Role

We are building a next-generation SDR-based wireless mesh network for real-time voice, video, and data in challenging environments. Our stack includes a custom PHY, frequency hopping, and multi-hop MANET routing.

We're looking for a Wireless Network Protocol Engineer who can bridge the gap between radio hardware (SDR) and Linux networking, designing robust MAC / link-layer protocols and integrating them with mesh routing (e.g., batman-adv).

If you enjoy making packets survive over noisy RF links, tuning protocols at MAC level, and working close to the metal, this role is for you.

Key Responsibilities

• Design & implement the radio MAC / link layer on top of our existing PHY:

Frame structure, sequence numbers, ARQ/retransmissions

Fragmentation / reassembly for larger packets

Basic QoS for voice, video, and file/data traffic

• Integrate the radio with Linux networking:

Expose the radio as a Linux network interface (netdev) (e.g., sdr0)

Make it work seamlessly with batman-adv or similar mesh / MANET protocols

Support standard IP networking over the mesh

• Work with frequency hopping and scheduling:

Implement time-slot based transmission and frequency hopping patterns

Design a link-layer scheduler that respects QoS and slot timing

• Performance & reliability:

Measure and optimise throughput, latency, and packet loss over multi-hop links

Tune parameters (MTU, retries, timers, CW, etc.) based on real-world tests

• Collaboration:

Work closely with the hardware / SDR / FPGA team on timing, RF tuning, and integration

Coordinate with application / AI / backend teams to understand traffic patterns and QoS needs

• Documentation & testing:

Write clear documentation for protocols, APIs, and configuration

Develop test plans, simulation setups, and on-device tests for various topologies

Must-Have Qualifications

• Strong proficiency in C for systems / embedded programming
• Solid understanding of computer networking fundamentals:
• Ethernet, ARP, IP, UDP/TCP
• L2 vs L3, routing vs bridging, MTU, fragmentation
• Hands-on experience with wireless protocols at MAC / driver level, for example:
• Wi-Fi (802.11), 802.11s mesh, Wi-SUN, LoRa/LoRaWAN, 6LoWPAN, ZigBee, or similar
• Experience with Linux networking:
• Working with network interfaces, routing, bridging
• Using tools like ip, tcpdump, wireshark, tc, etc.
• Exposure to at least one of:
• Mesh / ad hoc networking (batman-adv, OLSR, Babel, 802.11s, OpenWrt)
• Software Defined Radio (SDR) (USRP, GNU Radio, LimeSDR, etc.)

Nice-to-Have Skills

• Experience writing or modifying Linux network drivers (netdev):
• Familiarity with ndo_start_xmit, netif_rx, SKBs, and kernel networking APIs
• Knowledge of OFDM / COFDM, SNR, link budgets, and RF basics
• Experience with frequency hopping and time-synchronised TDMA or similar schemes
• Familiarity with OpenWrt or embedded Linux systems
• Experience with network security / crypto, such as:
• WireGuard, IPsec, TLS, or custom link-layer encryption
• Prior work on MANET research (ns-3 simulations, academic projects, theses, etc.)

What We're Looking For (Mindset)

• You like working close to the hardware, not just at the application layer
• You're comfortable debugging with tcpdump, Wireshark, logic analyzers, and RF tools
• You enjoy reading specs, protocol RFCs, and digging into kernel code when needed
• You can take a high-level we need voice + video over a mesh in bad RF conditions requirement and turn it into a concrete protocol and implementation plan