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Definition
| Very high frequency - low band for public safety includes the 39-72 Megahertz MHz bands. Channels in this frequency range tend to travel greater distances. |
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Definition
| For public safety includes 145-159 MHz bands. These are typically used by police, fire and ems for day to day operations |
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Definition
| Ultra high frequencies. Includes the 400MHZ, 500 MHz and 700 MHz, 800 MHz and 900 MHz frequencies. Freqencies in these ranges tend to not carry as far as those at lower frequencies, but penetrate structures better. |
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Definition
| All users share the same radio frequencies instead of having a channel dedicated to a department, talk groups are assigned. |
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Term
| Trunked mobile and portable radios |
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Definition
| Act like remote computers and are in continual contact with the base station. Channel selection is not controlled by the user. |
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Term
| Conventional (non-trunked) mobile and portable radios |
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Definition
| Usually installed in autos, aircraft, marine vessel. Specific fixed frequencies are assigned. Channel switching is controlled by user |
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Definition
| Limitations on how far a rado signal can and should travel. This is primarily to allow many municipalities/users to share the same radio channels. |
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Definition
| Basic radio system that transmits and receives on the same frequency. Does not require any base equipment. Helps resolve issues of a portable not being able to reach a base station when they are only trying to reach a nearby portable. |
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Definition
| Allows radio systems to provide coverage at a greater distance. Portable/mobile radios transmit on one frequency, while the base retransmits the signal on another frequency. |
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Term
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Definition
| Allows greater signal reception. Strategically place throughout a coverage area. Satellite receivers recive teh signal from a portable or mobile then send the signal, via microwave or landline, to a central controller which ehnse votes/selects the best audio signal coming from whichever satellite reciever is providing the best signal. |
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Definition
| Transmits a message over more than one transmitter. Allows for a robust and wide spread system. |
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Definition
| Uses voice vibration to send the voice to the transmitter. |
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Definition
| Voice is converted to a digital signal using a voice coder "vocoder". Then transmitted to a receiver and converted back to sound. |
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Definition
| Can be a radio ID number, to short messages, or special signals to indicate an emergency. Also includes radio to tranport MDT info, fingerprints, photos, maps, etc. |
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Definition
| Global positioning system. Developed by Department of Defense as a worldwide navigation and positioning tool. Uses 24 satellites to use as reference points. |
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Term
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Definition
| Is similar to VoIP, but augments two-way radio communications rather than telephone calls. With RoIP, at least one node of a network is a radio (or a radio with an IP interface device) connected via IP to other nodes in the radio network. |
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Term
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Definition
| Is similar to VoIP, but augments two-way radio communications rather than telephone calls. With RoIP, at least one node of a network is a radio (or a radio with an IP interface device) connected via IP to other nodes in the radio network. |
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