Weightless is an open-standard LPWAN technology developed by the Weightless Special Interest Group (Weightless SIG), a non-profit standards organization. Unlike Sigfox (proprietary, single operator) or NB-IoT (cellular-licensed), Weightless offers an open standard that any vendor can implement. The technology comes in three variants—Weightless-W, Weightless-N, and Weightless-P—each optimized for different use cases and spectrum allocations.
By the end of this chapter, you will be able to:
Before diving into this chapter, you should be familiar with:
LPWAN Fundamentals: Understanding core LPWAN concepts including long-range communication, ultra-low power operation, and trade-offs between range, data rate, and battery life provides essential context for Weightless technologies
Networking Basics: Knowledge of wireless communication fundamentals, frequency bands, modulation schemes, and network topologies helps understand Weightless variants’ technical differences
LoRaWAN: Familiarity with LoRaWAN architecture and capabilities provides a comparison baseline for evaluating Weightless’s market positioning and technical approach
Imagine you’re shopping for a car, and the dealer says “We have three models: the Economy for city driving, the Truck for hauling cargo, and the Luxury for long highway trips.” Each vehicle is optimized for different needs. Weightless is similar—it’s not one technology but three different versions (Weightless-W, Weightless-N, and Weightless-P), each designed for different IoT use cases.
Why three versions? Because there’s no “one size fits all” in IoT. Some applications need to send data both ways (sensors receiving commands), some only need to send (simple tracking), some need TV white space spectrum, and some need bidirectional communication with good battery life. Rather than forcing everyone to use one design, Weightless offers options.
The key innovation of Weightless-W is using TV white spaces—unused TV broadcast frequencies that became available when TV went digital. Imagine empty radio channels that no one is using—Weightless-W borrows these for long-range IoT communication. This gives excellent range and penetration through buildings.
Weightless-N is the simplest variant—one-way communication only (device to base station), ultra-low power, perfect for “report sensor reading every hour” applications. Weightless-P adds two-way communication, making it suitable for devices that need to receive commands or confirmations.
| Term | Simple Explanation |
|---|---|
| Weightless-W | Original variant using TV white space spectrum (bidirectional) |
| Weightless-N | Narrow-band variant—one-way communication only (ultra low power) |
| Weightless-P | Two-way communication variant—best balance of features |
| TV White Space | Unused TV broadcast frequencies available for unlicensed use |
| Open Standard | Anyone can implement—no single company controls it |
| ISM Band | Industrial, Scientific, Medical—unlicensed radio frequencies |
| Bidirectional | Two-way communication (device can send and receive) |
| Unidirectional | One-way only (device only sends, doesn’t receive) |
“Weightless sounds like a superhero name!” said Lila the LED.
Max the Microcontroller grinned. “It’s actually a family of open LPWAN standards created as an alternative to proprietary technologies. The Weightless SIG (Special Interest Group) designed three variants: W, N, and P – each targeting different use cases.”
“The coolest thing about Weightless-W,” said Sammy the Sensor, “is that it uses TV white spaces – unused TV frequencies that penetrate buildings incredibly well. Imagine sending your sensor data through walls and floors with ease because you’re using the same frequencies that TV signals use to reach inside every house!”
Bella the Battery noted: “Being an open standard means no single company controls it. Any manufacturer can build Weightless devices without paying licensing fees. That’s the same philosophy as WiFi and Bluetooth – open standards that anyone can implement. It drives down costs for everyone!”
The Weightless Special Interest Group was founded in 2012 to develop open standards for LPWAN communications. The organization includes members from across the IoT ecosystem: chipset manufacturers, network operators, system integrators, and end users.
Philosophy:
Weightless networks follow a star topology similar to LoRaWAN and Sigfox. End devices communicate directly with base stations (not through mesh routing), which reduces complexity and power consumption. The core network handles authentication, data routing, and application server integration.
Weightless-W’s use of TV white space spectrum provides excellent range and building penetration due to lower frequencies (470-790 MHz). However, TV white space availability varies by region and requires database coordination to avoid interfering with TV broadcasts.
This decision tree helps select the appropriate Weightless variant based on application requirements: throughput needs, spectrum availability, and bidirectional communication.
Weightless is designed for applications requiring: - Wide area coverage (urban and rural) - Low power consumption (multi-year battery life) - Low data rate communications - Cost-effective connectivity - Open standards (no vendor lock-in)
Example applications:
| Feature | Weightless-W | Weightless-N | Weightless-P |
|---|---|---|---|
| Spectrum | TV White Space (470-790 MHz) | Sub-GHz ISM | Sub-GHz ISM (868/915 MHz) |
| Data Rate | 1 kbps - 10 Mbps | 100 bps | 200 bps - 100 kbps |
| Range | 5+ km | 3 km | 2-5 km |
| Direction | Bidirectional | Uplink only | Bidirectional |
| Power | Medium | Ultra-low | Low |
| Status | Limited adoption | Discontinued | Active |
| Best For | High bandwidth, rural | Simple sensors | Most IoT applications |
Key Insight: Weightless-P has emerged as the primary variant due to its balance of features and simpler deployment (no TV White Space database required).
Use this tool to find the most suitable Weightless variant based on your requirements.
How does Weightless-W’s lower frequency (470-790 MHz TVWS) compare to Weightless-P (868 MHz ISM) for range? Consider free-space path loss (FSPL).
Path loss formula: \(\text{FSPL (dB)} = 20\log_{10}(d) + 20\log_{10}(f) + 32.45\) where \(d\) = distance (km), \(f\) = frequency (MHz)
Weightless-W at 600 MHz (TVWS midband): \[\text{FSPL}_{5\text{ km}} = 20\log_{10}(5) + 20\log_{10}(600) + 32.45 = 14.0 + 55.6 + 32.45 = 102.0\text{ dB}\]
Weightless-P at 868 MHz (ISM): \[\text{FSPL}_{5\text{ km}} = 20\log_{10}(5) + 20\log_{10}(868) + 32.45 = 14.0 + 58.8 + 32.45 = 105.2\text{ dB}\]
Frequency advantage: Weightless-W has 3.2 dB less path loss (lower frequency propagates better). With 20 dBm TX power and -124 dBm sensitivity (144 dB link budget): - Weightless-W margin at 5 km: \(144 - 102 = 42\text{ dB}\) (good for in-building penetration) - Weightless-P margin: \(144 - 105.2 = 38.8\text{ dB}\) (3.2 dB less penetration)
Range difference (assuming 100 dB path loss needed for reliability): - Weightless-W: FSPL = 100 dB → solve for \(d\): \(d = 10^{(100 - 55.6 - 32.45)/20} = 3.3\text{ km}\) - Weightless-P: FSPL = 100 dB → \(d = 10^{(100 - 58.8 - 32.45)/20} = 2.3\text{ km}\)
Conclusion: Weightless-W achieves 43% longer range (3.3 km vs 2.3 km) due to superior propagation at lower TVWS frequencies, but regulatory complexity limits deployments!
Scenario: A city deploys Weightless-W traffic sensors using TV white space spectrum at 600 MHz. How does the link budget compare to LoRaWAN at 868 MHz?
Transmit power: 20 dBm (100 mW, typical TVWS limit)
Receiver sensitivity: -124 dBm (Weightless-W narrowband mode)
Maximum link budget: 20 - (-124) = 144 dB
FSPL at 5 km, 600 MHz:
FSPL = 20*log10(5) + 20*log10(600) + 32.45
FSPL = 13.98 + 55.56 + 32.45 = 101.99 dB
Link margin at 5 km: 144 - 102 = 42 dB
(Sufficient for 2 concrete walls at 15 dB each + 12 dB fade margin)Transmit power: 14 dBm (25 mW, EU regulatory limit)
Receiver sensitivity: -137 dBm (LoRa SF12)
Maximum link budget: 14 - (-137) = 151 dB
FSPL at 5 km, 868 MHz:
FSPL = 20*log10(5) + 20*log10(868) + 32.45
FSPL = 13.98 + 58.77 + 32.45 = 105.20 dB
Link margin at 5 km: 151 - 105.2 = 45.8 dB| Parameter | Weightless-W (600 MHz) | LoRaWAN (868 MHz) |
|---|---|---|
| Link budget | 144 dB | 151 dB |
| FSPL at 5 km | 102 dB | 105.2 dB |
| Link margin at 5 km | 42 dB | 45.8 dB |
| Building penetration | 3.2 dB better (lower frequency) | Baseline |
| Effective indoor margin | ~45 dB | ~45.8 dB |
Key Insight: Despite LoRaWAN’s superior receiver sensitivity (-137 vs -124 dBm), Weightless-W’s lower frequency (600 vs 868 MHz) provides 3.2 dB better building penetration, making their effective indoor performance nearly identical. The real differentiator is spectrum access: TVWS requires database coordination and varies by region, while ISM bands are universally available.
Understanding why Weightless has limited market adoption despite technical merit:
| Factor | Weightless | LoRaWAN | Sigfox |
|---|---|---|---|
| Chipset vendors | 2-3 | 15+ (Semtech, STM, Nordic) | 5+ |
| Module cost (2025) | $15-25 | $5-12 | $3-8 |
| Global networks | < 10 | 200+ in 180 countries | 70+ countries |
| Developer community | Small | 500K+ developers | 100K+ |
| Standardization | Weightless SIG (open) | LoRa Alliance (open) | Sigfox SA (proprietary) |
| First deployment | 2015 | 2015 | 2012 |
| 2025 connections | < 500K | ~300M | ~20M |
Why Weightless Lost Market Share:
Lesson for IoT Protocol Selection: Technical superiority alone does not determine market success. Ecosystem health – chipset availability, developer tools, community support, and deployment track record – often matters more than raw specifications for long-term IoT deployments spanning 10-15 years.
Despite limited market adoption, there are specific scenarios where Weightless remains worth evaluating.
Consider Weightless-P when:
Consider Weightless-W when:
Default to LoRaWAN or NB-IoT unless one of the above conditions applies. Ecosystem health matters more than specifications for 10+ year deployments.
The Weightless paradox illustrates a fundamental tension in IoT technology selection:
Weightless proves that being open is necessary but not sufficient. LoRaWAN succeeded with an open standard AND aggressive ecosystem building (Semtech’s chipset subsidies, The Things Network community, 500K+ developers). Weightless had the open standard but not the ecosystem investment.
Weightless module availability and network infrastructure is limited compared to LoRaWAN or NB-IoT. Verify chipset and module availability, network operator presence, and development tool support before committing to Weightless.
Weightless-W operation in TV White Space requires querying a geolocation database to obtain available frequency assignments — this is a regulatory requirement. Devices must have GPS or network-provided location data to query the database.
:
Three Variants = Different Physics Trade-offs: Weightless-W (TV White Space, 470-790 MHz) offers superior building penetration (lower frequency) but requires cognitive radio complexity (geolocation database, spectrum sensing). Weightless-N (ultra-narrowband) maximizes battery life (uplink-only, no receiver) but sacrifices downlink (no firmware OTA, no commands). Weightless-P (ISM band) balances bidirectionality with deployment simplicity. Each variant optimizes ONE dimension at expense of others.
Open Standard does not equal Market Success: Weightless SIG published open specifications (anyone can implement), unlike Sigfox (proprietary). But openness without ecosystem support creates fragmentation — multiple vendors with incompatible implementations, no reference platform, no interoperability testing. LoRaWAN Overview succeeded with BOTH open standard AND ecosystem coordination (LoRa Alliance certification program).
LPWAN Landscape:
Technical Deep Dives:
Market Analysis:
| If you want to… | Read this |
|---|---|
| Study Weightless technical specifications | Weightless Technical Details |
| Compare Weightless with other LPWAN technologies | Weightless Market Comparison |
| Understand TVWS spectrum and regulations | Weightless Technical Details |
| Evaluate Weightless for your IoT deployment | Weightless Market Comparison |