Wikipedia Mobile Phone Signal
A mobile phone signal (or reception) is the signal strength (measured in dBm) of the connection to the mobile phone with its network. Depending on various factors, such as proximity to a tower, obstructions such as buildings or trees, etc., the signal may vary. Most mobile devices use a set of bars of varying heights to display the strength of the signal where the device is located. Traditionally five bars are used; see five by five.
Areas where cell phones cannot transmit to a nearby cell site, base station, or repeater are known as dead zones. In these areas, the cell phone is said to be in a state of outage. Dead zones are usually areas where cell phone service is not available because the signal between the handset and cell site antennas is blocked, usually by hilly terrain, excessive foliage, or physical distance.
A number of factors can create dead zones which may exist even in locations in which a wireless carrier offers coverage, due to limitations in cellular network architecture (the locations of antennas), limited network density, interference with other cell sites, and topography. Since cell phones rely on radio waves, and radio waves travel though the air and are easily attenuated, cell phones may be unreliable at times. Like other radio transmissions, cell phone calls can be interrupted by large buildings, terrain, trees, or other objects between the phone and the nearest base station antennas.
Many wireless service providers work continually to improve and upgrade their networks in order to minimize dropped calls, access failures, and dead zones (which they call “coverage holes” or “no-service areas”).
Arbitrary Strength Unit (ASU) is an integer value proportional to the received signal strength measured by the mobile phone.
It is possible to calculate the real signal strength measured in dBm (and thereby power in Watts) by a formula. However, there are different formulas for 2G and 3G networks.
- dBm = 2 × ASU – 113, ASU in the range of 0..31 and 99 (for not known or not detectable)
- dBm = ASU – 116, ASU in the range of -5..91 and 255 (for not known or not detectable)
It is widely disbelieved[by whom?] that ASU = “Active Set update”. The Active Set Update is a signalling message used in handover procedures of UMTS and CDMA mobile telephony standards. On Androidphones, the acronym ASU has nothing to do with Active Set Update. It has not been declared precisely by Google developers.
Mapping Mobile Phone Signal
Coverage Map. User enters details to receive specific information regarding their mobile phone carrier. Read full article HERE
Another website that shows mobile phone signal, it also does exactly what I suggested earlier, it allows users to add different networks and additional information. Seems to be an American only site – HERE
BBC Website – Data 3G & 2G Coverage HERE
About the data
The data displayed on the map was collected by people who chose to participate in our survey by downloading the app to their phone. The data only provides a snapshot of the mobile coverage experienced by this self-selecting group over a short period. The BBC has not attempted to balance the participants either geographically or by service provider.
Each box on the map indicates the average reception within that area over the survey period. Areas showing no coverage could be the result of a single phone losing signal. The map does not take into account factors such as reduced reception while in buildings. The map is not intended to replace the service providers’ own coverage maps when making a decision about taking out a mobile phone contract.
In terms of my map and data I will need to decided how I will decided what is high or low signal strength. Do I want to show places that are only full signal spots? Or do I also want to show locations that have weak or medium signal? Is that necessary information to know. I think personally I would only care about full signal spots, but I do know some people love to wonder while on the phone, perhaps knowing where the signal will get weak will stop them wondering off to far so that their call drops.
This also brings up another issue, how will I divide up the space? By square meters? Or general sections such as stairs, door ways etc. There are a lot of questions, which I need to think of, as it would not be helpful for these questions to arise while half way through my project. I think I will need to find out from other students what they would need from this map.