Month: January 2015
Angulation (Angle-Based) Techniques
Localization is based on the angle of the received signal.
Angle of Arrival (AoA) / Direction of Arrival (DoA)
AoA determines the angle of Incidence at which signals arrive at the receiving sensor. This angle is used to estimate the location of the device using the intersection of the two lines of bearing (LoB) formed by a radical line to each receiving sensor. For 2D planes, 2 receivers are needed. When at least 3 receivers are used, this is known as triangulation. Read the rest of this entry »
Received Signal Strength (RSS)
Localization is based on the received signal strength. The RSS is measured either by the mobile device or by the receiving sensor.
The following information is needed to calculate the distance between the sensor and the device:
- Transmitter output power
- Cable losses
- Antenna gain
- Path loss model(PL)
CCNP Wireless 642-747 IUWMS Summary Notes 3 : Location Tracking Techniques – Lateration (ToA and TDoA)
Distance-Based (Lateration) Techniques
The tracking position is determined based on distance. The distance can be measured in three different ways:
- Using Time of Arrival (ToA)
- Using Time Difference of Arrival (TDoA)
- Using Received Signal Strength
In ToA and TDoA, localization is based on propagation time, whereas for RSS systems, propagation is based on signal strength.
Tracking systems are classified by the measurement technique that they use. Real Time Location Systems (RTLS) are grouped into the following:
- Cell of Origin ( Nearest Cell)
- Lateration ( depending on Distance)
- Angulation (depending on the angle)
- Location patterning ( pattern recognition)
Advantages of Location-based services.
Location-based services helps us to:
- Effectively locate assets and personnel.
- Improve productivity by locating effectively.
- Reduce unauthorized removal of assets and, thus, helps reduce losses.
- Improve customer satisfaction
- Improve WLAN planning and tuning
- Coordinate device location with Security policy enforcement
- Determine rogue device location
- Monitor health and status of key assets.
- Wi-Fi Location-Based Services 4.1 Design Guide by Cisco Press.
Happy New Year and thank you for sticking with me thus far !
In this post, I will share my CUWSS experience.
I finished studying for my CUWSS Exam in the beginning of December and booked my again for around December the 15th. My first attempt to give the exam was unsuccessful :(. To be honest, I was rather lazy during my preparation and was not as dedicated as was supposed to be. I did not go the extra mile to look for information and that might have contributed to my failure. I thought that going through the Study guide for the previous version of the exam (since I could not access the newer one), the Quick Reference Guide from v2.0, the IP Expert Videos for v1.0 and my extensive WiFi experience was enough to ace that exam, but No! I Failed. Read the rest of this entry »