Low-power electronics are not a single product category in the military domain — they are an enabling capability that cuts across almost every aspect of modern defence operations. From a sensor buried in a hillside that has not needed a battery change in three years, to a soldier’s biometric monitor that streams vital signs over a body-area network, to a drone payload that maps a minefield on a single charge — ultra-low-power design is the common thread.
This post maps the six major domains where low-power electronics are deployed operationally or are the subject of active military research and acquisition programmes.
1. Unattended Ground Sensors (UGS)
Unattended Ground Sensors are among the most mature and operationally proven applications of low-power electronics in the military. A UGS is a small, typically covert sensor node placed in terrain to detect and report on the movement of personnel, vehicles, or materiel — without requiring a human presence.
How they work
Modern UGS nodes use a layered detection architecture:
- Always-on front-end sensors — seismic geophones, passive magnetic sensors, or PIR (passive infrared) detectors run continuously at nanowatt to low-microwatt power levels. They consume so little energy that a single lithium primary cell can power them for years.
- Hardware comparator / wake-up trigger — when the always-on sensor detects a signal exceeding a threshold (a footfall, a vehicle engine, a metallic mass), it fires a hardware interrupt, consuming no software overhead.
- Main processing and radio — the microcontroller and RF subsystem power up, classify the detection event (personnel vs. vehicle, direction, speed estimate), and transmit a compressed encrypted report. This active phase may last 200–500 ms before the system returns to sleep.
This “asleep yet aware” architecture is the fundamental design pattern of DARPA’s N-ZERO programme (see Case Study 1) and is now standard in commercial and military UGS products.
Sensor modalities
| Modality | What it detects | Standby power |
|---|---|---|
| Seismic (geophone) | Ground vibration from footsteps, vehicles | 1–10 µA |
| Acoustic (MEMS microphone) | Engine noise, voices, gunshots | 5–50 µA |
| Passive magnetic (magnetometer) | Ferrous metal mass (vehicles, weapons) | 1–5 µA |
| PIR (passive infrared) | Body heat movement | 1–10 µA |
| Daylight camera | Visual imagery on trigger | 0 (gated off) |
| Seismic + camera combined | Multi-modal confirmation | Wake-up chain |
Current platforms
- McQ RANGER — US-made multi-sensor ground node with encrypted RF reporting, seismic and acoustic detection, multi-year battery life
- Bertin Technologies POLARIS — European multi-modal network with acoustic and seismic channels, NATO-qualified under STANAG 4370
- Textron Unattended Ground Sensor — used by US Army for persistent perimeter surveillance and route monitoring
Standards compliance required
UGS platforms must meet MIL-STD-810H (environmental), MIL-STD-461G (EMC), and IP67 minimum for ground burial in wet terrain. European and NATO procurement additionally requires STANAG 4370 / AECTP-200 qualification.
2. The Internet of Battlefield Things (IoBT)
The Internet of Battlefield Things is the US Army’s formal framework for connecting heterogeneous tactical assets — sensors, robots, vehicles, soldiers, aircraft — into a unified data fabric that enables machine-speed situational awareness and decision support.
Origins and research infrastructure
The US Army Research Laboratory (ARL) established IoBT as a research programme in 2016. In 2017, ARL formed the IoBT Collaborative Research Alliance (IoBT-CRA), bringing together university, industry, and government researchers around five core problem areas: network architectures, perception, analytics, security, and — critically — energy.
A 2025 survey published in Springer Nature’s Discover Internet of Things journal (“The Internet of Battle Things: a survey on communication challenges and recent solutions”) identifies power and energy management as one of the four primary bottlenecks preventing IoBT from scaling to operational deployment.
Why energy is the IoBT constraint
Consider a tactical operation deploying 500 sensor nodes across a 10 km × 10 km area. If each node requires battery replacement every three months, that is 2,000 battery maintenance visits per year — each requiring a logistics sortie into potentially contested terrain. If each node operates for three years between maintenance visits, that becomes 167 visits per year — a fundamentally different operational proposition.
IoBT energy research focuses on:
– Energy harvesting — solar, thermoelectric, vibrational, RF energy scavenging to supplement or replace primary batteries
– Energy-aware routing — network protocols that route data through nodes with more remaining energy, balancing load across the network
– Dynamic duty cycling — adaptive sleep schedules based on threat level, time of day, and network traffic patterns
– Wake-up radio architectures — ultra-low-power secondary receivers that listen for a wake-up signal while the main radio sleeps
IoBT vs. commercial IoT
IoBT shares technology with commercial IoT — many IoBT research nodes use LoRa, 802.15.4, or Bluetooth LE radios — but the operational requirements diverge sharply:
| Requirement | Commercial IoT | IoBT |
|---|---|---|
| Security | TLS / certificate-based | Military encryption, TEMPEST, anti-jam |
| Operating environment | Indoor / urban / controlled | All terrain, all weather, −55 °C to +70 °C |
| Network infrastructure | Fixed gateways, cloud backhaul | Ad hoc mesh, satellite backhaul, denied comms |
| Adversarial context | None / minimal | Active jamming, direction-finding, physical capture |
| Lifetime | 2–5 years | 5–10 years |
| Component qualification | Commercial | MIL-PRF-38535 or equivalent |
3. LoRa and LPWAN for Tactical Military Applications
LoRa (Long Range) is a chirp spread-spectrum physical layer developed by Semtech, originally for civilian smart city and utility monitoring applications. Its combination of ultra-low transmit power (~25–100 mW), kilometre-scale range (2–15 km depending on terrain), and sub-mW standby consumption has made it an active subject of military research as a tactical edge radio.
Why LoRa is attractive for military edge sensing
- No infrastructure dependency — LoRa works point-to-point or in star topology without a fixed network. Nodes can report to a mobile gateway mounted on a vehicle, UAV, or carried by a soldier.
- Penetration — at 433 MHz (an evaluated military band), LoRa penetrates foliage and building materials significantly better than 2.4 GHz Wi-Fi or cellular frequencies.
- Power budget — a LoRa end node transmitting once per minute draws an average current well under 1 mA, enabling 6–24 months on a standard AA lithium cell.
- Spread spectrum — LoRa’s chirp modulation is inherently resistant to narrowband interference and provides some natural protection against jamming and interception, though it does not provide military-grade COMSEC without additional encryption layers.
Key research findings
2017 (IEEE): “A Long-Range Low-Power Wireless Sensor Network Based on U-LoRa Technology for Tactical Troops Tracking Systems” demonstrated LoRa-based soldier position reporting at 5 km range in open terrain and 2 km in forested areas, with node current draw under 1 mA average and full BOM cost under $15 at prototype scale.
2018 (ResearchGate): “Evaluating LoRaWAN-based IoT devices for the tactical military environment” identified LoRaWAN as a viable physical layer for logistics tracking and non-critical sensor reporting in tactical environments, with key caveats around duty-cycle limits and the need for additional encryption.
2019 (IEEE): “Investigating LoRa for the Internet of Battlefield Things: A Cyber Perspective” conducted a security analysis of LoRa in IoBT scenarios, confirming that LoRa’s physical-layer spread spectrum provides measurable resistance to detection, while recommending end-to-end AES-256 encryption for message confidentiality.
2025 (IEEE): “Design and Implementation of a LoRa-Based Tactical Communication System Using Low-Power Sensors” presented a complete implementation enabling real-time sensor data transfer, situational awareness display, and encrypted command messaging in a degraded communications environment — without relying on any fixed infrastructure.
Limitations and mitigations
LoRa in its standard LoRaWAN protocol stack is subject to regional duty cycle limits (1% in the EU 868 MHz band), limited payload sizes (up to 242 bytes per transmission at low spreading factors), and lacks native military-grade COMSEC. Military deployments mitigate these through:
– Operation on dedicated military frequency allocations outside civilian LoRaWAN bands
– Custom protocol stacks (such as ThingsLog’s Open LoRa Protocol) that optimise payload efficiency and allow longer transmission windows
– Application-layer AES-256 encryption on all payloads before LoRa transmission
4. Soldier-Worn and Body Sensor Networks
Modern infantry soldiers are becoming mobile sensor platforms. The devices they carry — or will carry in the near future — include:
- GPS position tracker and inertial navigation unit
- Encrypted voice and data radio
- Helmet-mounted camera and night-vision system
- Biometric health monitor (heart rate, core temperature, hydration, stress indicators)
- Ballistic protection sensor (impact detection)
- Weapon-mounted sight with thermal and digital zoom
- Handheld mission terminal
The power demand from this electronics load during active operations can exceed 20 W. Carrying sufficient battery capacity for a 72-hour mission without resupply would add more than 5 kg to the soldier’s load — on top of an already unsustainable burden.
Body Sensor Network (BSN) architecture
The research response to this problem is the Body Sensor Network — a short-range wireless network that connects all worn sensors to a single hub device:
- Each individual sensor (health monitor, weapon sight, GPS) transmits its data over an ultra-low-power short-range radio (Bluetooth LE, ANT+, IEEE 802.15.4 / Thread) to the body hub.
- The body hub aggregates all sensor streams and manages the single, higher-power uplink radio that communicates with the platoon network or satellite link.
- Power is distributed from a single large central battery in the plate carrier, eliminating the redundant weight of individual per-device batteries.
A PMC-published study (“Systematic Analysis of a Military Wearable Device Based on a Multi-Level Fusion Framework”) proposes a four-level data fusion hierarchy for BSN data — raw sensor, feature extraction, decision fusion, and command output — with energy-aware processing assigned to whichever level consumes least power for each data type.
Current programmes
US Army CombatConnect (PEO Soldier): A smart hub integrated into the plate carrier that distributes data and power to worn devices via a common interface. Designed to meet MIL-STD-810H for dismounted infantry operations. See Case Study 4 for full details.
Elitac Wearables (Netherlands): European developer of tactical wearable sensor harnesses for NATO land forces, integrating biometric monitoring, GPS, and encrypted radio into a low-profile soldier-worn system.
Energy harvesting research: The US DoD is funding development of kinetic energy harvesting that converts the mechanical energy of walking into electrical power — potentially recovering 5–10 W from normal infantry gait, enough to sustain low-power wearable electronics indefinitely.
5. UAV and UGV Sensor Payloads
Small unmanned aerial systems (sUAS) — quadrotors, fixed-wing gliders, loitering munitions — have become standard features of peer and near-peer military operations. The payload mass budget for a tactical sUAS is typically 100–500 g; the power budget for the payload is 1–10 W.
Every milliwatt saved in the sensor payload translates directly into extended flight time, longer range, or a smaller and quieter airframe.
Low-power payload design for UAVs
Triggered imaging: Rather than streaming video continuously, a low-power electro-optical (EO) or infrared (IR) sensor operates in triggered mode — a low-power motion detector or acoustic sensor wakes the camera only when a target is detected. The camera captures a burst of imagery, transmits it compressed over a low-power data link, and returns to sleep.
Edge AI inference: Running neural network inference on-board the UAV payload (rather than streaming raw video to a ground station) can reduce the data transmission power budget by 90% or more. Neuromorphic processors — which mimic the event-driven spike-based computation of biological neural systems — can perform object recognition at under 100 mW, compared to several watts for a conventional GPU-based approach.
LoRa telemetry: For slow-update-rate sensor data (environmental, chemical, radiation), LoRa provides a data link capable of multi-kilometre range at a fraction of the power cost of 4G LTE or satellite modems. ThingsLog LoRa hardware has been evaluated for small UAS payload integration in environmental monitoring applications.
UGV sensor payloads
Unmanned ground vehicles carry heavier payloads with larger power budgets, but their sensor subsystems still benefit from low-power design:
– Acoustic array: passive listening for IED detonation events, using ultra-low-power always-on microphone arrays
– Chemical detection: ion mobility spectrometry (IMS) sensors that duty-cycle their ionisation source, reducing average power by 80–90% compared to continuous operation
– Seismic: ground-coupled geophones for buried object detection, operating at microwatt levels between scan events
6. Space and High-Altitude Military Assets
Military small satellites and high-altitude pseudo-satellite (HAPS) platforms face the most extreme version of the power constraint: solar energy is the only available source, thermal cycling from sunlight to eclipse imposes extreme stress on electronics, and no maintenance is possible after launch.
Low-power electronics for space military applications must comply with:
– MIL-PRF-38535 Class V/S — the highest tier of military IC qualification, including full radiation hardness assurance (RHA)
– MIL-STD-461 — EMC in the spacecraft environment
– Total ionising dose (TID) and single-event effects (SEE) qualification for all active components
LoRa-based satellite-to-ground communication using small LEO cubesats has been demonstrated in commercial programmes (Lacuna Space, Sateliot), and military research is evaluating similar architectures for covert sensor exfiltration — using the satellite pass overhead as the communication window, with the ground sensor sleeping between passes.
Series Navigation
- Why Low Power Matters in Military Operations
- Key Application Domains
- How Military Low-Power Electronics Are Built
- Protective Coatings for Military Electronics
- Military Electronics Standards
- IP Ratings and Ingress Protection
- Case Study: DARPA N-ZERO
- Case Study: LoRa Tactical Troop Tracking
- Case Study: ThingsLog LPMDL in Antarctica
- Case Study : Army CombatConnect
- Case Study 4: Army CombatConnect
