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Hawaii Pre(imittary Technical Assessmen! lCTAP-HUHA-PRRASSESS-00/-RO fielded an 800 MHz system they, too, could purchase dual band radios for any users that may need interoperability with State agencies while also being able to purchase less expensive 800 only radios from an array of vendors for users that would not require interoperability. Available Number of Frequencies in Each Band The existing Counties access to 800, according to the Macro's Needs Assessment document (page 4-$)is: The County received an allocation of 24 channels, each channel a paired set of frequencies with a basemobile frequency separation of 45 MHz. The County does not have any FCC licenses for these frequencies. Should the County decide to build a system using this set of frequencies, the County will have to submit the FCC application to the Region 11 committee for review and approval prior to submission to a public safety coordinator. The approval letter from the committee becomes part of the FCC application, which is generally granted with very little delay. The Conceptual Design Analysis & Recommendation Report states the following (page 2-5): Based upon Macro's experience, a 15 channel trunked system would meet current and future needs for communications through 2025 under normal, emergency and critical incident types of communications. But the Channel Plan on page 2-10 shows 35 channels required for voice traffic. ICTAP concerns over the discrepancy between saying 15 channels are sufficient and proposing a design which requires 35 channels. The County is presently licensed for approximately 28 VHF frequencies occupying 25 kHz bandwidth. With careful choice of location, these frequencies could be expanded to 56 frequencies using 12.5 kHz which is the bandwidth occupied by P25 Phase 1.56 frequencies form 28 frequency pairs, each frequency pair is a channel in a trunked system. We were unable to provide an independent assessment of the channel requirements because neither the Needs Assessment nor Conceptual Design document showed a clear number of existing users, the breakdown of users by discipline, or the projected growth. Additionally the Call For Service - 2007 table on page 2-10 of the Conceptual Design document is unclear. Are the numbers in this table individual radio transmissions or radio conversations? These numbers plus the user information would be required to properly assess the number of channels required. The County has very unique terrain considerations with vastly spaced population centers but a 35 channel system appears to be too large for a population base of approximately 172,000 full- time residents plus a significant influx of visitors. Cost Considerations From a straight equipment cost standpoint, migrating to a new P-25 system will be approximately the same cost for the County regardless of the frequency band. In other words, a VHF base station is approximate the same cost as an 800 MHz base station. 700 MHz may not be quite as affordable as the demand is still much lower compared to the other bands. However, since a VHF system would require fewer sites, a significant costs savings could be realized: Regardless of which band is chosen, all subscriber units (mobiles and portables) owned by the County would need to be replaced with P25 capable radios in the proper frequency band. If the County decides to proceed with either 700 or 800 MHz, we would recommend that the RFP be written to allow 700 or $00 MHz or a combination of both bands. In other words, do not restrict the RFP to just one band or the other. This could potentially increase competition and lower costs. October 2008 ~ t2