UWB مقابل البلوتوث: مما يوفر دقة أفضل لتحديد المواقع في الأماكن المغلقة

لقد دخلنا عصر تحديد المواقع في الأماكن المغلقة بشكل جيد وحقيقي – سواء كان ذلك من خلال أنظمة تتبع الأصول, الخدمات القائمة على الموقع أو أدوات التنقل المتقدمة, indoor positioning is revolutionizing how we interact with enclosed spaces. The demand for accurate indoor positioning is only set to intensify – Markets and Markets projects the indoor positioning market to reach $31.4 مليار بواسطة 2029! But implementation success hinges on choosing the right technology – the reliability of any indoor positioning system is only as good as its underlying tracking method. في هذه المقالة, we compare two leading contenders in the space – النطاق العريض الفائق (UWB) and Bluetooth Low Energy (أصبح) – to help you determine which technology best suits your indoor positioning needs.

Available indoor positioning technologies today

When out and about, we often rely on GPS to find our way around. It picks up signals from satellites orbiting Earth and achieves roughly a 5 – 20 meter level of accuracy. ومع ذلك, GPS has its limitations – once we step inside a building or head underground, those satellite signals get distorted. كنتيجة ل, GPS becomes much less accurate indoors.

This is where Bluetooth and Wi-Fi positioning systems step in. These technologies based on received signal strength can help us locate objects and people within a few meters, making them suitable for basic indoor navigation. But technology is moving forward – new technologies like UWB and Bluetooth 5.1 aim to deliver even higher sub-meter accuracy down to just a few centimeters. This unlocks highly precise indoor applications for interaction with various actors in the environment like hands-free access control, تتبع الأصول, وأكثر بكثير.

What is UWB and how it provides location

UWB is a short-range wireless technology that operates through low-powered radio frequencies. It operates within at least 500 MHz bandwidth, من 3.1 إلى 10.6 غيغاهرتز. You might wonder if this range interferes with other technologies. في الواقع, no. Here’s why: UWB transmits data through nanosecond pulses without a carrier wave, using incredibly low power levels – just -41.3 dBm/MHz. فى السنوات الاخيرة, the IEEE 802.15.4z amendment has improved the MAC and PHY layers for ranging and localization purposes.

UWB mainly offers four methods to position objects and people:

• ToA (Time of Arrival)
• TDoA (Time Difference of Arrival)
• TWR (Two-Way Ranging)
• AoA (زاوية الوصول)

It’s worth noting that most companies choosing UWB for asset tracking prefer TDoA because of its low power consumption, which extends tag battery life.

UWB TDoA vs ToA vs TWR vs AoA

The TDoA technique is very similar to ToA, as both rely on measuring signal propagation time. ومع ذلك, TDoA has a clever advantage: it only needs receiver time synchronization, not absolute timing. In TDoA, tags broadcast signals to anchors, which relay the data to a central server. The positioning engine at the server then calculates the time differences of arrival to determine the tag’s location, achieving an accuracy of 10 إلى 30 سم. To perform this calculation, the server needs timestamps from a minimum of four anchors.

TWR works different, relying on individual tag-anchor ranging, but it’s more complex – requiring nine travel back and forth messages for a single position calculation. As for AoA? حسنا, it’s pricier and less accurate, and it’s not the popular go-to choice in UWB positioning.

How does Bluetooth enable location

Bluetooth is a frequency-hopping radio technology transmitting data in packet, which operates in the 2.4 نطاق جيجاهرتز. There are two main categories: Classic Bluetooth (الإصدارات 1.0-3.0) and Bluetooth Low Energy (أصبح, إصدار 4.0 و لاحقا). The key difference? استهلاك الطاقة! BLE is specifically designed for low power consumption applications.

Bluetooth RSSI vs Bluetooth AoA/AoD

Prior to Bluetooth 5.1, BLE was widely used for indoor positioning using RSSI (Received Signal Strength Indicator) to measure path loss and estimate distances between transmitters and receivers. ومع ذلك, traditional BLE asset tracking was more about proximity than precise location – if you wanted better accuracy, you had to deploy more beacons into the area.

في 2019, the Bluetooth SIG updated the 5.1 core specification with enhanced direction-finding capabilities. This specification enables asset tracking using Angle of Arrival (AoA) or Angle of Departure (AoD) by utilizing antenna arrays to determine signal direction, achieving positioning accuracy within 1 متر. AoA requires multiple antennas at the receiver, while AoD needs implementation at the transmitter.

حاليا, most commercial implementations still rely on RSSI due to its simplicity and widespread hardware support. ومع ذلك, Bluetooth AoA is creating quite a buzz in the positioning market by combining BLE’s cost-effectiveness with UWB-level precision. MOKO SMART has already launched tags and gateways that support this high-precision Bluetooth AoA positioning.

At the time of this writing, بلوتوث 6.0 has been released, with a focus on Bluetooth Channel Sounding. It uses phase-based ranging (PBR) and round-trip time (RTT) for secure and fine ranging between devices. More distance awareness applications are waiting for us to explore!

Comparison of UWB vs Bluetooth positioning

We’re witnessing some exciting battles in indoor positioning technologies. UWB and Bluetooth are both making waves, but they each bring something unique. Let’s zoom in on UWB and Bluetooth AoA to compare them against each other.

Precision and Coverage

UWB has a clear advantage in positioning accuracy, achieving centimeter-level precision (typically 10-30 سم) due to its ultra-wideband characteristics, which is hard to match with other narrowband systems. بالاضافة, UWB signals can pass through obstacles, such as walls/floors, and machines, and are therefore ideal for complex industrial environments.

نظريا, UWB can cover up to 200 أمتار. In large, open spaces, you will require fewer devices to cover the same area. في المقابل, Bluetooth AOA has a smaller coverage range and is significantly affected by installation height.

Want to see these solutions in action? We’ve deployed both Bluetooth AOA and UWB positioning systems at the MOKO factory – reach out to us for a demo video!

Interference Resistance

At the same data transmission rate, UWB outperforms Bluetooth in interference resistance. ال 2.4 GHz frequency band used by Bluetooth is getting pretty crowded, with interference from various devices and networks. UWB, ومع ذلك, leverages its higher frequency band and unique signal characteristics to maintain rock-solid performance even in complex wireless environments.

استهلاك الطاقة

In comparison of minimum average power consumption, BLE typically takes the win, consuming less power than UWB. But here’s the interesting part – in real-world applications, the difference might not be as dramatic due to the operational mode of tags! In BLE AOA or UWB cloud computing mode, tags spend most of their time in sleep mode, only waking up to transmit signals while the network handles positioning calculations. Their life can last up to 1-2 سنوات. If using a device-side computing mode, where tags must stay awake longer, their lifespan may drastically reduce to just a few weeks or days.

Deployment Challenges

Practically, it is usually easier to implement UWB TDoA. Its time-based algorithms are relatively simple, while Bluetooth AOA systems need multiple calibration points – زمن, زاوية, and anchor positions all need to be just right.

علاوة على ذلك, UWB maintains high accuracy across various environments, including complex building structures. But for Bluetooth AOA? It’s a bit more sensitive to environmental changes. Sometimes it requires extra calibration, or may require additional base stations to maintain optimal performance in some challenging spaces.

Cost and Scalability

Now we come to costs, Bluetooth AOA and UWB TDOA base stations are in a similar price range, but there’s a significant difference in tag costs. Bluetooth AOA tags are more budget-friendly than their UWB counterparts – a difference that really adds up in large-scale deployments. Bluetooth AOA’s cost-effective tags could save you substantial money if you plan to track numerous assets.

Comparison table of UWB vs BLE RSSI vs BLE AoA

UWB or BLE: the choice for indoor positioning

Choosing the right indoor positioning solution isn’t a one-size-fits-all decision. We need to take various factors into consideration: the environment, system architecture, existing infrastructure, ميزانية, وبالطبع, the positioning precision. If you need high accuracy, UWB and BLE AoA are the way to go. If precision isn’t your top priority, Bluetooth RSSI positioning might be your best bet – it’s practical and cost-effective.

For high-precision positioning, the choice between Bluetooth AOA and UWB really comes down to your specific use case. If you’re tracking a limited number of high-value assets with extreme precision? UWB TDoA is probably your best bet. If you’re looking to track numerous assets with “pretty good” صحة? Bluetooth AOA’s lower tag costs and decent precision might be the way to go. Don’t forget about system compatibility – Bluetooth positioning is more widely supported across various devices. ومع ذلك, UWB integration typically needs more specialized hardware and software.

Here at MOKO SMART, we’re all about getting you the IoT devices that fit your needs. Our product range includes various منارات بلوتوث, مجسات, BLE AoA tags, alongside our UWB tags. We don’t just throw technology at you – we’ll help you figure out exactly what devices make sense for your specific situation.