Recipient Organization
CATALYST COMMUNICATIONS, TECHNOLOGIES, INC.
2107 GRAVES MILL RD., SUITE D
FOREST,VA 24551
Performing Department
(N/A)
Non Technical Summary
Forest Service and other first responder dispatchers need a tool to manage the migration from analog conventional to digital P25 transmissions and to link P25 control stations. In the long-term, conventional audio should be converted to the P25 format before it is routed across the network. In the short-term, some forests will need P25 audio converted to the analog format that they are using today for network connectivity. In Phase I of this SBIR, Catalyst Communications Technologies will work to demonstrate the feasibility of routing P25 voice and control messages to standard PCs and legacy radios across a shared IP network. The voice will be decoded on an external board to postpone the licensing and development costs associated with decoding within the PC. Phase I will also demonstrate the feasibility of controlling a P25 radio across a shared IP network and allow forests and other agencies to begin leveraging P25 functionality in the next three years instead of
waiting ten to fifteen years when all radio equipment has been converted to P25. Finally Catalyst would develop a standard for all radio and console manufacturers for controlling control stations across a shared IP network.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Goals / Objectives
We propose to research new techniques and algorithms specifically optimized to link Project 25 radio users to dispatchers and radio users that do not have P25 radios. This research will require that Catalyst convert the proprietary messaging from P25 control stations to a format optimal for transport across an Internet Protocol network. Voice information, in its native digital format, will be inserted in and carried by the User Datagram Protocol (UDP) and routed using the unicast transport method. Control and messaging will be carried using the Transmission Control Protocol (TCP). The resulting technology will allow any authorized personal computer on the agency network to talk with any two-way radio, P25 or legacy. Likewise, existing analog radios will be able to monitor calls from new digital radios using the advanced P25 formats. The objective of this Phase I SBIR is to prove the feasibility of connecting a P25 control station to a shared Internet Protocol (IP)
network using only digital signals in a robust implementation. We plan to demonstrate that with the network 60% loaded, voice traffic following a typical USFS profile, meets or exceeds Circuit Merit 3 intelligibility standards and that control messages are accurate at least 97% of the time. Further we plan to demonstrate that the latency added by network routing is less than 1 second and jitter is less than 50 ms. These results should be further improved in Phase II. A secondary Phase I objective is to create a proposed standard for USDA and DOI to specify operations and connectivity of a P25 RoIP solution. The ultimate goal of this project is to prove the feasibility of integrating Project 25 digital radios with conventional analog radios in a seamless, high-performance, Radio over IP network (RoIP). In Phase I we will investigate the problem of creating a digital interface between a P25 control station and the RoIP network. Specifically, Catalyst, with the assistance of Virginia
Tech, will research creating a digital interface between a P25 control station and a PC, routing the P25 IMBE audio across the IP network in its native digital format, and optimizing of P25 signaling across a shared IP network. We will develop a minimum feature set with associated messaging for all mobile radio vendors and offer it to the USDA and DOI as a standard. Based on the results of our research, we will design software for standard personal computers to send and receive digital P25 signals across a shared IP network to connect P25 digital radios to one another, to conventional analog radios, and to dispatchers.
Project Methods
The Phase I approach is geared toward achieving the project objectives and will be conducted as follows: Task 1. We will research the creation of a digital interface between a Project 25 control station and a personal computer. The first task to be undertaken is to provide a digital connection between a P25 control station and a Catalyst server PC. Catalyst will then need to develop prototype application layer software to control this radio and monitor the 2.4 kbps over-the air embedded signaling with digital messages. We will also need to design an interface to convert the 4.4 kbps Improved Multi-Band Encoding voice to IP traffic. Task 2. We will research routing P25 audio across an IP network without converting it to analog. First Catalyst will need to convert the 4.4 kbps Improved Multi-Band Encoding voice to UDP packets. Task 3. We will research the optimization of P25 audio and control messages across a shared IP network. The P25 voice and control signaling must be
carried over the network in a way that preserves audio quality by minimizing latency and jitter or delay variation, while minimizing the impact on other network traffic. Task 4. We will develop test bed software to test the feasibility of linking P25 digital radios to analog dispatch positions across a shared IP network. An application layer protocol will be developed to efficiently route voice packets and control messages between a P25 server and a dispatch PC (client). These messages will use industry standard TCP/IP and unicast UDP/IP protocols as its transport. TCP/IP control messages between client and server will include changing channel, enabling and disabling encryption, field radio ID, and scan control. Voice packets will be carried in unicast UDP/IP packets between client and server. Task 5. We will carry out a thorough validation/feasibility test to determine that audio quality and control signaling capability are acceptable using the P25 digital signaling across the
network. To validate the feasibility of this task the following test approach will be taken. A test bed with a P25 control station programmed with different frequencies will be connected to a server PC. That PC will be connected via an IP network to a client PC with the external IMBE codec board. Test calls will be placed in both directions on different channels. The client PC will be used to control the channel selection, the scan setting, and the encryption setting on the P25 control station. Audio quality, latency, and bandwidth will be measured. The recorded audio can then be played back to determine its quality. Task 6. We will assess Phase I results in terms of technical and economic feasibility and prepare a final Phase I report including a proposed USDA/DOI standard for P25 RoIP. Catalyst Communications Technologies will prepare a report that summarizes the Phase I results and presents recommendations for follow-on Phase II research and Phase III commercialization. This report
will include a stand-alone proposal for a P25 RoIP interface that will be circulated amongst Forest Service Radio Program Managers, DOI radio managers, mobile radio manufacturers, and other industry players.