SENER Aeroespacial Concept Receiver for Indoor Positioning Techniques (SCRIPT) is a technological demonstrator
that takes advantage of new technological developments in location systems based on wireless technologies, in
combination with new techniques for position estimation and data fusion for ubiquitous indoor positioning.
This work is supported by ESA Contract Nº 4000133576/20/NL/CRS.
SCRIPT is an innovative solution for a Cost-Efficient Indoor Positioning with Sparse Local Infrastructure:
• Offering mass-market wireless technologies based on low-cost COTS HW.
• Wireless technologies which are complementing GNSS to cover indoor environments.
• Inertial and position measurements to enhance the resilience of the positioning solution.
The fusion of commercial technologies approaches the challenged quasi-ubiquitous indoor positioning accuracies:
• UWB (Ultra-Wide band) that enables fine time resolution, which allows identifying direct path received
signal, mitigating multipath effect very effectively.
• WiFi RTT (Round Trip Time) taking advantage of the widespread use of WLAN access points that allows use
of simple infrastructures.
• Bluetooth is widely adopted in consumer market and supports AoA/AoD with relatively simple HW.
• The CTTC’s (Centre Tecnològic Telecomunicacions Catalunya) GNSS Receiver is expanded to include high
sensitivity algorithms in signal acquisition.
• The activity investigates the potential of 5G waveforms for ranging and direction of arrival estimation by
a 5G emulation.

The capacity of developing navigation algorithms for data fusion are key aspects covered in SCRIPT. Fusion
navigation solutions based on ranging, direction of departure (DOD) and direction of arrival (DOA) and GNSS based
on single and multiple anchors and peers for outdoor-to-indoor scenarios are developed.
Our own concept in the field of data fusion for indoor/outdoor location, based on a Sigma Point Kalman Filter
(SKPF), the hybrid filter that combines a particle filter with the classical Kalman filter, is used. The SW Receiver
applications are implemented based on Open-Source SW.
Peer to peer/Collaborative positioning algorithms, exploiting ranging and/or Angle of Arrival /Angle of Departure
(AoA/AoD) data between different Remote Units, are deployed as well.