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Philadelphia Police Department Interview
June 1, 2000
Sgt. Greg Masi

System Structure

How many users of the system?  Police?  Fire?  Other services?
There are 1500 mobile and 2900 portable users of the system in the police department.

Problems with too many users wanting access at a given time?
There are 12,000 9-1-1 calls that may generate dispatches.  Sometimes, a user must wait for a turn to use the radio.  There is a state of "radio contention."

Problems with frequency allocations?
The current police system is a thirty-year-old UHF system.  It has fourteen channels.  The new digital system under contract with Motorola has thirty channels.

How many tower locations?
The new system will have ten simulcast sites.  The new system will also have satellite repeaters to enhance portable coverage of the city.

Do the tower locations provide adequate coverage of the city?
The city has 90% coverage now, with no coverage underground.  The new system will provide 95% coverage 95% of the time.

System Performance

Problems with interference?
Overmodulation on the channels of the Philadelphia Fire Department is more of a problem.  This occurs even with the Channel Guard technology from General Electric.

Problems with missed radio calls/cutoffs?
There are some dead spots with portables.

Problems in major emergency/disaster with overuse?
There are some problems with overuse in an emergency.

Problems with system failing entirely?
There have been some partial failures with the transmitters.  The transmitters operate on a "voter" system.

Problems with related support systems, such as computers and 911 services?
The 9-1-1 system is separate from the radio system.  An RCM card might fail.  The system is "PG based."  The consoles have gone down, but the city has redundancies.  The city has 800 MDTs, operating on the CDPD protocol (cellular structures).

How satisfied with the system are the dispatchers?
The dispatchers are satisfied that the system "works for them."

How satisfied with the system are officers?
Officers report that when there is no "radio contention," they are satisfied with the system.

How satisfied with the system are communications managers/support personnel?
Masi states that there is "never enough money."  And even after spending $53 million for the new system, it "still does not cover underground."

Is interoperability a problem, especially in major incidents?
The police cannot talk with fire personnel.  Interoperability is also a problem within the police department.  There is no mutual aid frequency for communicating with neighboring communities.  Officers must use an emergency channel to talk to other communities.

System Cost

How much did the current system cost?
Masi had no information on the cost of the current system.  The city communications manager (Director of City Communications) handles cost matters.

How much are maintenance costs per year?
See answer to above question.

Will upgrading to the new digital trunked system decrease maintenance costs?
The new system will decrease maintenance costs.

Adequate funding for maintenance/upgrades?
Masi notes that an additional $25 million would be required for underground coverage.  He did say that Philadelphia has had a seamless system for contacting units underground for ten years with the current systems in place.

Is cost-benefit analysis used in determining upgrades/procurement?
Masi is unsure whether cost-benefit analysis is used.

System Upgrades

What are planned upgrades to radio system?
The new $53 million radio system will be APCO-25 compliant and a Motorola ASTRO system.  It will also utilize FDMA technology.

What are planned upgrades in support systems (e.g. CAD, MDTs, Enhanced 911, etc.)?
The MDTs are four years old.  No upgrades are planned with them, except that they may be upgraded to new hardware, using CDPD technology.

How will the new digital trunked system help/hurt the city?
A trunked system would help the city realize gains in interoperability, radio contention, clarity, and in-building coverage.  A digital system requires more sites and coverage studies.  The city has 127 square miles to cover, roughly the same area that Baltimore had to cover with their new digital trunked radio system.  Masi reports that Baltimore is happy with the coverage from their system, because they did extensive coverage studies.  Masi said that Philadelphia has been in contact with Baltimore in developing their own digital trunked system. 

Are upgrades sometimes foregone because of inadequate funding?
Masi said that the age of the system "dictated what we had to do [in upgrading the current system]."

System Politics

Disagreements with local government over technology upgrades?
The Director of City Communications tries to work with departments about upgrades.

Conflicts with communications managers and radio manufacturers (Motorola, GE, etc.)?
There have been minor conflicts with vendors in delivery of systems.

How satisfied is the public with the system?
Masi said the public "knows" about the new system.

Other Notes on the New 800 MHz Digital Trunked System

Masi says that during the Republican National Convention (RNC), the police will work from their current UHF channels.  The 800 MHz system cannot be utilized at this time.  There will be "no major 800 use" during the RNC.  There may be some tests, however.  The first users of the 800 system will come online at the end of 2000, and the police may come online at the end of 2001, but Masi was not positive about this statement.  Public works and the fire department will be the first users of the 800 system.


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