Since its intial rollout in 1985 with three carriers using an analogue-based system, the cell phone industry has evolved and grown into a product and service that have become almost essential to out everyday lives. Now, 25+ years later we have multiple carriers offering various services marketed towards key consumer segments. There are a number of carriers that build and maintain physical networks; Bell, Rogers, Telus, Wind (and Shaw turning on spring 2011), although there are many brand names reselling services on those networks (Koodo, Solo, Fido, Virgin, PC Choice, 7-11, etc). Below is a chart outlining the technology breakdown of the carriers and their physical networks.

CARRIER (in Alberta)	NETWORK	VOICE Frequency Band	DATA Frequency Band
Calgary3 & Edmonton	CDMA	1900 MHz	1900 MHz
Calgary3 & Edmonton	HSPA1,5	800 & 1900 MHz	800 & 1900 MHz
in rural areas	CDMA	800 MHz	800 MHz
in rural areas	HSPA1	800 & 1900 MHz6	800 & 1900 MHz6
in all areas	Mike (iden)	800 MHz2	800 MHz2
in most urban areas	CDMA	1900 MHz	1900 MHz
in most urban areas	HSPA1	1900 MHz (see Telus info)	800 MHz (see Telus info)
in rural areas4	CDMA & HSPA1	800 & 1900 MHz	800 & 1900 MHz
in all areas	GSM	800 & 1900 MHz	800 & 1900 MHz
in all areas	AWS	1700/2100 MHz	1700/2100 MHz
in all areas	AWS	1700/2100 MHz	1700/2100 MHz

1 this is a joint-venture network shared between Telus & Bell
2 this 800 MHz band is not the same as the cellular 800 MHz band and requires different amplifier equipment
3 this includes (to some degree); Airdire, Crossfield, Cochrane, Bragg Creek, Turner Valley, Black Diamond, Okotoks, High River, Chestermere, Strathmore
4 in rural Alberta, Bell Mobilty uses Telus' network
5 both 800 MHz & 1900 MHz are used as needed for voice and/or data in the majority of the city now
6 some high traffic areas now have 1900 MHz assignments as well, such as; Rocky Mountain House, Fort McMurray, Grande Prairie, Red Deer, Lethbridge, Medicine Hat - in fact Telus is deploying dual-band equipment on many many towers throughout the province

Voice Band includes: voice calls, standard text messaging, and voicemail notification
Data Band includes: multimedia text messaging, email, and web browsing

Each hardware device is specific to a carrier and is also specific to a network for that carrier. 
The frequency assignments (aka channels) in a given frequency band are unique to each carrier.

There are a number of carrier towers throughout the city, province, and country. For example, Telus has over 450 CDMA towers in Alberta and about 125 in Calgary alone.

Some towers are exclusive to a specific carrier and others are shared by multiple carriers.

Tower height is very important in that a shorter tower will more likely be affected by terrain and obstructions.
Cellular signals will not penetrate or go over hills or metal structures.
(see coverage plot pictures in "getting started")

Antenna placement on a given tower is generally one of two configuration types. The most common type is three antennas placed 120 degrees apart with the first pointing roughly north. The second type is two antennas 180 degrees apart pointing along a road and/or through a valley.