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El‑Sheimy and Li Satell Navig (2021) 2:7 Page 8 of 23

Table 6 New WiFi, BLE, 5G, and LPWAN features that can enhance PLAN
Technology New feature
WiFi Long range, low power consumption in WiFi HaLow (WiFi‑Alliance 2020); high‑precision ranging in WiFi RTT (IEEE 802.11 mc) (IEEE 2020)
BLE Long range in BT long range (BT 5) (Bluetooth 2017); high‑precision direction fnding in Bluetooth 5.1 (Bluetooth 2019)
5G Higher base station density (Andrews et al. 2014), mmWave Multiple‑Input And Multiple‑Output (MIMO), large‑scale antenna, and
beamforming (Witrisal et al. 2016), device‑to‑device communication (Zhang et al. 2017a), new measurement types (del Peral‑Rosado
et al. 2017)
LPWAN Low cost, low‑power consumption, long range, new measurement types (Li et al. 2020a)

three application categories (Restrepo 2020), includ- thus enhance PLAN performance. Also, it is feasible to
ing Ultra-Reliable and Low-Latency Communication add new measurement types (e.g., TDoA (Leugner et al.
(URLLC) for high-reliability (e.g., 99.999% reliable under 2016) and AoA (Badawy et al. 2014)) into the 5G and
500 km/h high-speed motion) and low-latency (e.g., mil- LPWAN base stations.
lisecond-level) scenarios (e.g., vehicle networks, indus- Most of the existing research on 5G and LPWAN based
trial control, and telemedicine), enhanced Mobile Broad PLAN is based on theoretical analysis and simulation
Band (eMBB) for high-data-rate (e.g., gigabit-per-second- data because there are limited real systems. Te stand-
level, with a peak of 10 gigabits-per-second) and strong ard for mmWave signal has been late and therefore it is
mobility scenarios (e.g., video, augmented reality, virtual difcult to fnd the hardware for experimenting. Te
reality, and remote ofcing), and massive Machine-Type accuracy ranges from 100-m-level to centimeter-level,
Communication (mMTC) for application scenarios (e.g., depending on the base station deployment density and
intelligent agriculture, logistics, home, city, and environ- the type of measurement used. Te survey paper (Li et al.
ment monitoring) that have massive nodes which have a 2020a) provides a systematic review of 5G and LPWAN
low cost, low power consumption, and low data rate. standardizations, PLAN techniques, error sources, and
5G has strong potential to change the cellular-based mitigation. In particular, it summarizes the PLAN errors
PLAN. First, the coverage range of 5G base stations may by end-device-related errors, environment-related errors,
be shrunk from kilometers to hundreds of meters or base-station-related errors, and data-related errors. It is
even within 100 m (Andrews et al. 2014). Te increase important to mitigate these error sources when using 5G
of base stations will enhance the signal geometry and and LPWAN signals for PLAN purposes.
mitigate Non-Line-of-Sight (NLoS) conditions. Second, Tere are indoor PLAN solutions based on other types
5G has new features, including mmWave Multiple-Input of environmental signals, such as the magnetic (Kok and
and Multiple-Output (MIMO), large-scale antenna, and Solin 2018), acoustic (Wang et al. 2017), air pressure (Li
beamforming. Tese features make it possible to use et al. 2018), visible light (Zhuang et al. 2019), and mass
multipath signals to enhance PLAN (Witrisal et al. 2016). fow (Li et al. 2019a).
Tird, 5G may introduce device-to-device communi-
cation (Zhang et al. 2017a), which makes cooperative Navigation and positioning sensors
PLAN possible. Inertial navigation system
Meanwhile, the newly-emerged IoT signals and the An INS derives motion states by using angular-rate and
Low-Power Wide-Area Network (LPWAN, e.g., long- linear specifc-force measurements from gyros and accel-
range (LoRa), Narrow Band-IoT (NB-IoT), Sigfox, and erometers, respectively. Te review paper (El-Sheimy and
Long Term Evolution for Machines (LTE-M) have the Youssef 2020) summarizes the state of the art and future
advantages such as long-range, low-cost, low-power- trends of inertial sensor technologies. INS is tradition-
consumption, and massive connections (Li et al. 2020a). ally used in professional applications such as military,
Figure 3 demonstrates the communication ranges of 5G aerospace, and mobile surveying. Since the 2000s, low-
and LPWAN signals, with a comparison with other wire- cost MEMS-based inertial sensors were introduced into
less technologies. the PLAN of land vehicles (El-Sheimy and Niu 2007a,
5G and LPWAN systems provide a possibility for the b). Since the release of the iPhone 4, MEMS-based iner-
wide-area localization in indoor and urban areas. Simi- tial sensors have become a standard feature on smart-
lar to 5G, LPWAN systems no longer require an extra phones and have brought in new applications such as
communication module that costs $ 10 level in the cur- gyro-based gaming and pedestrian indoor PLAN. Table 7
rent PLAN systems. LPWAN signals are compatible with compares a typical inertial sensor performance in mobile
more and more smart home appliances. Tese nodes will mapping and mobile phones. Diferent grades of iner-
increase the deployment density of IoT networks and tial sensors have various performances and costs. Tus,