Fiber Optics for Correctional Facilities
Fiberoptics plays an integral part in various aspects of the correctional market including:
- Remote visitation within the facility
- Remote arraignment in conjunction with associated courthouses
- Video & audio surveillance within the facility, exercise yards, perimeter security, etc.
Correctional facilities are well-suited for fiber as many of the cable runs can be quite long including both indoor and outside installations. Exercise yards afford an ideal location for fiberoptics, particularly in lightening prone areas. One of the key features of fiberoptics is its immunity to lightening. Reliable video surveillance is of paramount important in correctional facilities. In the presence of lightening, any camera located outdoors is a prime target. Without fiber, the lightening pulse can travel down the copper cable and damage the entire communications/surveillance center. Utilizing fiber for transporting the video from the CCTV to the communications center isolates any lightening-induced pulse to the camera only – thus protecting the communications center.
Fiber also easily allows the facility to transport many signals over an individual fiber. This affords the user the ability to consolidate the signals in a single or several locations and multiplex them over a very small number of fibers – reducing equipment and installation costs.
Remote visitation and arraignment are closely related in that they both allow long distance audio and video communications without jeopardizing the safety of the personnel. These systems also minimize the expenses associated with transporting inmates to locations common with either the visitor or the presiding judge as it would be in an arraignment case.
The quality of video over an IP network is dependent on several factors including the number of nodes and cameras on the network. Latency associated with PTZ control can become an issue in certain situations. However, real-time fiber systems provide live, full-resolution video without the quality constraints of an IP system. At the main security location, the video & audio can be recorded in real time leaving nothing to the imagination or legal interpretation. If ‘networking’ the video is important, the video can be converted to an IP signal after it is received and recorded at the headend location. In this type of ‘hybrid’ system architecture, the quality of the video is maintained as long as possible and practical before it is converted to a less than optimal IP format.
Since fiber is also ‘signal proof’ different quantities and types of signals can be easily multiplexed on an individual fiber. This offers the facility expansion capabilities not available in traditional copper solutions. Fiber’s advantages make it the obvious choice for correctional and courthouse system architectures.
Mecklenburg County Jail, Charlotte North Carolina
Meridian Technologies was chosen as the fiber optic equipment supplier used within the Mecklenburg County Jail facilities in Charlotte, NC for remote visitation within the facility. The systems incorporate bi-directional video & audio for remote visitation. There are presently six visitation stations located at the main entrance to the facility, each with its own video & audio communication channels. The video & audio signals are routed from the main PBX system to the equipment bay located in the access space above the inmate housing units. Each of the eight inmate housing unit has two such visitation stations for a total of sixteen channels of video & audio. There are two of these equipment bay locations, one for each of the four inmate housing units.
A combination of video & audio multiplexers was used to transmit these various signals to and from the visitors’ center to the associated inmate locations. All of the signals are transmitted over standard 62.5/125µm multimode fiber. Due to fiber count limitations, wavelength multiplexing was used to consolidate a number of the video & audio channels onto one fiber. Special care had to be taken in the system design to ensure that the multimode fiber’s bandwidth could support the optical transmission data rate of the equipment. As such, the shorter wavelength (850nm) having a lower overall bandwidth was used to transmit 8 audio channels while the longer wavelength (1300nm) with a high fiber bandwidth was used to transmit the 8 video channels. As a result, the system provided high-quality video and audio over the long distances required while keeping within the bandwidth constraints of the fiber and maintaining adequate optical loss budget.
Expansion capabilities have been provided so that this visitation center can be easily expanded with no impact on the existing fiber system while providing a cost-effective and efficient way to add more remote visitation locations as demand dictates.
The fiber transmission equipment incorporates a number of diagnostic features to afford fast and efficient troubleshooting of the entire system – from camera and microphone to the monitor and speaker. At each location, indicator lights provide indication of the operational status of each incoming signal as well as the condition of the fiber transmitter, receiver and fiber infrastructure.
