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Observing my cellphone switch towers
11–20 of 137 posts
Re: Observing my cellphone switch towers
#12> Along the way, five towers and nine cells (a.k.a eNB for Evolved NodeB) What does this mean? Whats the diff between tower and cell?
It's explained in the article, one tower can have multiple antennas (author found out they're typically set at 120°) on a single mast. Each antenna is then a cell, altough mounted on a single tower.
Ah multiple antennas. Makes sense. Thanks!
Re: Observing my cellphone switch towers
#13Nice, that would be really nice to have for large Wi-Fi systems in big commercial buildings too.
This is exactly how (big) wifi systems work. (mesh)
If this is not the case in a big commercial building, it was done by choice or because of incompetence.
Re: Observing my cellphone switch towers
#14The iPhone entries in the table could give a misleading impression of the timing. UMTS 3G phones had long been commonplace by the time the iPhone 1 was announced.
Re: Observing my cellphone switch towers
#15> Along the way, five towers and nine cells (a.k.a eNB for Evolved NodeB) What does this mean? Whats the diff between tower and cell?
it gets even more fun when you throw in beamforming.
a tower is just a mast on which radios are mounted. a site is the location of the equipment. a node is the name for a set of radios and base systems. a nodes service can be divided in to sectors. a cell is usually a certain coverage area served, the frequency of cells will differ a bit from it's neighbor to stop interface. and a beam is specific focused radio that serves one UE.
Re: Observing my cellphone switch towers
#16This is nicely done, and takes me back to when I worked in mobile network planning.
Most people are blissfully unaware of how much radio chatter and constant adjustment is actually holding up their browsing session from second to second, with the UE negotiating the best possible terms (power, throughput, etc.) with adjacent cell towers before it decides (or is prompted) to hand-over to a new cell.
Optimizing cell hand-over and adjacency matrices is something that operators need to do quite frequently as traffic patterns and network topology change and a computationally neat problem that can be scaled horizontally (I once optimized one such job to run in 4 hours instead of 24).
Re: Observing my cellphone switch towers
#17Would be great to have an app that shows a map with my position and the position of the current cell. And that could create such maps as in the article on-the-fly.
Anybody knows of such an app?
Re: Observing my cellphone switch towers
#18This is nicely done, and takes me back to when I worked in mobile network planning. Most people are blissfully unaware of how much radio chatter and constant adjustment is actually holding up their browsing session from second to second, with the UE negotiating the best possible terms (power, throughput, etc.) with adjacent cell towers before it decides (or is prompted) to hand-over to a new cell. Optimizing cell han…
Um, I'm pretty sure that there is not much of that handover stuff happening while browsing hacker news since that's likely in a low-velocity scenario, i.e., sitting on the toilet.
Re: Observing my cellphone switch towers
#19This discussion reminded me of an iOS app that visualized cell towers in AR. I can't remember the name, though.
Re: Observing my cellphone switch towers
#20On a related note, this same mechanism can be used as a fallback for GPS to determine device location.
I have worked on an IoT device with builtin SIM in the personal alarm space. Often when a device is indoors no GPS fix can be found, but the GSM module can report all celltower ids in range with signal strengths. These can be used to triangulate the device location. Google has an API for this where you can pass celtower ids and signal strengths.
edit: and of course similar triangulation fallbacks/methods can be applied to WiFi AP's or Bluetooth Beacons, if you have a database with APs or beacons and their location. This database can be externally sourced but also built automatically by sending celltower ids/aps/beacons along with GPS fixes. I assume this is one of the many things Google is doing with their fleet of Streetview cars.