Wireless

Wireless is a Colonial term used to describe short- to medium-range electromagnetic communications between two sources over a practical distance, e.g. between vessels or ship-to-surface. The term is also used as a noun to describe the device used to pick up wireless broadcasts, such as a "shortwave wireless."

Wireless appears to work using frequencies available from a similar electromagnetic spectrum as used on the Earth we live on today. Shortwave transmissions exist in the Colonial wireless spectrum ^{(TRS: "Miniseries")}. With this similarity, wireless is limited in range based on other celestial bodies, antenna direction, nuclear and other man-made EM interference, distance (where the time to send or receive a message might be measured in minutes and not fractions of a second), and broadcast reception or transmission limits of the vehicles in communication. A Raptor, for instance, may be able to hear transmissions from its mother ship, Galactica, but may be too far away to return a reply as it may not have as strong a wireless transceiver than Galactica to push the message.

Repeaters and Communications Relays

Wireless transmissions are real-time sans noticeable time delay, meaning that some kind of transmission system utilizing repeaters would need to be in use throughout the Colonies. During the Fall of the Twelve Colonies, Galactica is able to tie into a separate feed via a communication relay within range of Colonial One, and able to receive both real-time DRADIS updates and wireless transmissions before a Cylon missile attack on One ^{(TRS: "Miniseries, Night 1")}.

The Cylons also make use of communication relays for similar purposes ^{(TRS: "Razor")}. Wireless technologies may also be tied into their resurrection process, which requires a Resurrection Ship to be in range of Cylon units in order to carry out the intended purpose ^{(TRS: "Resurrection Ship, Part I", "The Hub")}.

Transmission Range

A passenger on Colonial Heavy 798 picks up information from their shortwave wireless about the nuclear bombing of Caprica ^{(TRS: "Miniseries")}.

Sharon Valerii uses a communication drone to extend her Raptor's transmission range in principle after her ship leaves Caprica with several refugees during the Cylon Attack ^{(TRS: "Miniseries")}. The drone contains an automated distress call with its own wireless transmitter. She uses to the probe in hopes of transmitting her call for help outside of the Cylon fleet, which were jamming many Colonial communication channels.

Hand-Held Units

Emergency wireless handsets are included with a Viper pilot's emergency ejection survival kit. Unfortunately for Starbuck, her handset is smashed on her parachute landing on a desolate moon, forcing her to seek alternate means to return to the Fleet ^{(TRS: "You Can't Go Home Again")}.

Similarly, Karl "Helo" Agathon and the Caprica-copy of Sharon Valerii use a handset to track down the disaster beacon, leading them to a fallout shelter in a Caprican cafe's basement ^{(TRS: "You Can't Go Home Again")}.

Ship-based Communications

On advanced battlestars, wireless communication between CIC and other departments of the ship may likely be the standard mode of communication. On ships such as Galactica, however, communication is done through hardwired phones and public-address systems per Commander Adama's orders that no networked computers (including communication computers) be used on board to avoid Cylon infiltration.

Wireless is also used for civilian communication, such as the Talk Wireless network for public Fleet entertainment and programming.

Notes

In the real-world, "radio" is the common term for the type of communications that BSG's wireless represents. In this sense, "wireless" should not be confused with the current American context of cellular telephony or wireless digital networking. The term "radio", however, is used by Dr. Baltar in the episode "33" while talking to Laura Roslin about communications with Olympic Carrier, but this is probably an actor's error, much like Colonel Tigh's exasperated "Jesus" in the Miniseries.
"Wireless" is an archaic term for radio in the UK which fell out of favor in the 1960's. It has since been replaced by the term "radio" among contemporary Britons.
It can be inferred that dead humanoid Cylons transmit their memory and personality data to a Resurrection Ship or facility by some form of wireless. However, the Cylons themselves have never referred to their ship-to-ship communications by this term.