Public Safety Radio System System Overview

Frequencies vs. Channels A frequency is a point in the radio spectrum part of what describes a channel A channel is a set of parameters that can include one or more frequencies, CTCSS tones, name, etc. Example: VCALL10 is a channel with transmit and receive frequency 155.7525 MHz, CTCSS tone of 156.7 Hz 2/22/2013 Radio System Overview Revision -

Simplex Radio Channel Using 1 Frequency Each User Must be Line of Sight with Each Other Very Reliable Limited Range 2/22/2013 Radio System Overview Revision - 3

Repeater Radio Channel Using 2 Frequencies Frequency 1 Used to Talk from Radio to Base Frequency 2 Used to Talk from Base to Radio Each User Must be Line of Sight with Base Enhanced Range Frequency 1 Frequency 2 2/22/2013 Radio System Overview Revision - 4

Base Station – Simplex Some units don’t hear transmission because of obstructions. Dispatcher relays message so it is heard by all units Unit 1 Dispatch Center Unit 2 Unit 3 2/22/2013 Radio System Overview Revision - 5

Base Station – Repeater All units within range of repeater hear all transmissions through the repeater Dispatch Center Unit 1 f2 f1 RX TX Unit 4 Unit 2 Repeater Unit 3 2/22/2013 Radio System Overview Revision - 6

Type of Systems Single Site Everything Located at One Site Multiple Site Remote Receive Sites Simulcasting 2/22/2013 Radio System Overview Revision -

Single Site Coverage limited to units within range. 2/22/2013 Radio System Overview Revision -

Remote Receivers Voter (comparator) chooses best received signal and sends that signal to: Simplex - Dispatch Repeater - Transmitter Voter Central Transmitter Remote Site Link (microwave, phone line, etc.) Users do not need to change channel depending on location. System (voter) automatically picks best receive tower site. RX Only Site 2/22/2013 Radio System Overview Revision -

Simulcasting The same information is transmitted on the same channel at the same time from multiple locations. Central Transmitter Remote Site Link (microwave, phone line, etc.) Remote Site Remote Site 2/22/2013 Radio System Overview Revision -

Radio System Centrally Located Tower Radio transmissions to/from mobile units take place from this site. Remote Receiver Sites to “Hear” Users Fills in holes in system reception Simulcast Paging Sites Additional Radio Channels 2/22/2013 Radio System Overview Revision -

License Additional Channels Emergency Management Repeater Law Enforcement Repeater Fire / EMS Repeater Paging Repeaters Two Scene Tactical Channels Jail Operations Channel 2/22/2013 Radio System Overview Revision -

Base Sites Six Main Tower Locations Independence Tower Aurora Water Tower Rowley Water Tower Fairbank Tower Jesup Water Tower Court House Tower 2/22/2013 Radio System Overview Revision -

Tower Layout 2/22/2013 Radio System Overview Revision -

Fire / EMS Operational Channels PAGING FIREOPS 1 Repeater, Main Dispatch / Operations Channel FIREOPS 2 Simplex, Secondary Dispatch / Operations Channel VFIRE21 (State Fire) Simplex, Interoperability Channel FIRETAC1 & FIRETAC2 Two On Scene Tactical Channels 2/22/2013 Radio System Overview Revision -

Law Operational Channels LAWOPS 1 Repeater, Main Dispatch / Operations Channel LAWOPS 2 Simplex, Secondary Dispatch / Operations Channel LAW INFO Simplex, Dispatch Information Channel VLAW31 (Law Mutual Aid) Interoperability Channel CF LEA Law Tactical Channels LAWTAC A (Analog) or LAWTAC D (Digital) 2/22/2013 Radio System Overview Revision -

EMA / Roads Operational Channels EM OPS Repeater, Main Dispatch / Operations Channel ROADS JAIL OPS Simplex, Dispatch Information Channel 2/22/2013 Radio System Overview Revision -

Interoperability Channels Iowa Channel VHF “VTAC” Channels Surrounding Jurisdictions 2/22/2013 Radio System Overview Revision -

Aurora Site Channels Transmit (Tx) “Talk” Receive (Rx) “Hear” PAGING LAWOPS 1 FIREOPS 1 FIREOPS 2 EM OPS ROADS 2/22/2013 Radio System Overview Revision -

Fairbank Site Channels Transmit (Tx) “Talk” PAGING Receive (Rx) “Hear” LAWOPS 1 FIREOPS 1 FIREOPS 2 EM OPS ROADS 2/22/2013 Radio System Overview Revision -

Jesup Site Channels Transmit (Tx) “Talk” Receive (Rx) “Hear” PAGING LAWOPS 1 FIREOPS 1 FIREOPS 2 EM OPS 2/22/2013 Radio System Overview Revision -

Rowley Site Channels Transmit (Tx) “Talk” Receive (Rx) “Hear” PAGING LAWOPS 1 FIREOPS 1 FIREOPS 2 EM OPS ROADS 2/22/2013 Radio System Overview Revision -

Independence Site Channels Transmit (Tx) “Talk” PAGING LAWOPS 1 LAWOPS 2 FIREOPS 1 FIREOPS 2 EM OPS ROADS Receive (Rx) “Hear” PAGING LAWOPS 1 LAWOPS 2 FIREOPS 1 FIREOPS 2 EM OPS ROADS 2/22/2013 Radio System Overview Revision -

Court House Site Channels Transmit (Tx) “Talk” LAW INFO VLAW31 VFIRE21 JAIL OPS PT TO PT CF LEA VCALL10 UCALL40 8CALL90 UBUCLINK Receive (Rx) “Hear” LAW INFO VLAW31 VFIRE21 JAIL OPS PT TO PT CF LEA VCALL10 UCALL40 8CALL90 UBUCLINK 2/22/2013 Radio System Overview Revision -

Mobile Only Channels Transmit (Tx) “Talk” Receive (Rx) “Hear” CAR 2CAR LAWTAC A LAWTAC D FIRETAC1 FIRETAC 2 REGMED VMED28 Receive (Rx) “Hear” CAR 2CAR LAWTAC A LAWTAC D FIRETAC1 FIRETAC 2 REGMED VMED28 2/22/2013 Radio System Overview Revision -

Channels With Best Coverage Repeaters PAGING Hear from all tower locations. Talk from all tower locations. 2/22/2013 Radio System Overview Revision -

Channels With Best Coverage Repeaters LAWOPS 1 FIREOPS 1 EM OPS ROADS Simplex FIREOPS 2 Hear from all tower locations. Talk from just Independence. 2/22/2013 Radio System Overview Revision -

Channels With Good Coverage Repeaters LAWOPS 2 Hear from just Independence. Talk from just Independence. 2/22/2013 Radio System Overview Revision -

Channels With Lowest Coverage Simplex LAW INFO VLAW31 VFIRE21 JAIL OPS PT TO PT VCALL10 UCALL40 8CALL90 UBUCLINK Hear from just Court House. Talk from just Court House. 2/22/2013 Radio System Overview Revision -

Things to Remember With a Repeater, can see each other and may not be able to talk to each other. The Repeater has to be able to Hear and Talk to both of you. When this happens, switch to a simplex channel, FIREOPS2, FIRETAC, VFIRE. 2/22/2013 Radio System Overview Revision -

Things to Remember With a Repeater, what you say will be head throughout the county. With a Simplex channel you are heard only as far as the radio carries (Handheld shorter distance than a mobile). Dispatch can hear the best with the towers and remote receive sites. 2/22/2013 Radio System Overview Revision -

Things to Remember With a remote receivers, there will be cases that dispatch can hear you but can not talk to you. Dispatch can hear better then talk due to remote receive sites. This was done to ensure handheld coverage. 2/22/2013 Radio System Overview Revision -