Leikhim and Associates will interview potential users of the new radio system to determine their specific
requirements and concerns. Initial “buy in” by end users of any new project is necessary for a successful
outcome and the input of the users is essential. The requirements of the users will be compared with the
capabilities of the existing system to perform a gap analysis. This analysis will be further utilized within a
technology assessment when comparing potential solutions.
Leikhim and Associates will include the user group in follow on sessions to discuss potential technology
solutions. These sessions are important to confirm user requirements and set reasonable expectations
for the new technology.
Leikhim and Associates encourages the user group to participate in the functional and voice coverage
testing of the system as their knowledge of the operational requirements, experience with the technology
and “ownership” of the project will provide a credible assessment of the system performance.
Assessment of existing infrastructure for life cycle and future use
Leikhim and Associates will evaluate the existing communications facilities to assess their suitability for use
in a new or upgraded radio system. Overall physical conditions of safety and security, physical accessibility,
environmental protection, HVAC, electrical power sources and capacity, network connectivity, grounding and
bonding techniques (Such as Motorola R56) and equipment growth capacity will be noted. Existing conditions
at each site will be noted appropriate recommendations provided where conditions are lacking. Communication
antenna support structures will be observed noting any issues of available capacity, insufficient grounding or
bonding, loose appurtenances, hardware or unsecured cables.
For structural analysis of towers including capability of supporting existing or new loads, physical conditions of
decay or subsidence, Leikhim and Associates will subcontract at your request, a licensed structural engineer
for further analysis and report.
Technology Assessment
The technology assessment is an essential component of the new project. Technology that is commercially
available “off the shelf” is attractive to meeting the near term requirements of a successful system upgrade at
low risk, while the pursuit of new and innovative technology to meet extended long-range plans of the system
may require exploration of riskier and more speculative technologies. Finding a balance that will meet near
term goals while providing avenues for growth and continuous technology improvement is the aim of the
technology assessment.
System Design and Technical Specifications
Radio Frequency (RF) planning and propagation analysis
To ensure that a radio system design meets requirements of end users including Public Safety agencies,
Leikhim and Associates follows design guidelines prescribed in the industry approved standard EIA/TIA
TSB-88 (WIRELESS COMMUNICATIONS SYSTEMS –PERFORMANCE IN NOISE AND INTERFERENCE -
LIMITED SITUATIONS RECOMMENDED METHODS FOR TECHNOLOGY INDEPENDENT MODELING,
SIMULATION, AND VERIFICATION).
We are experienced in radio propagation analysis using a variety of industry-accepted software
modeling tools such as EDX Signal Pro, RFCAD, ComSite Design, RapTr, and Mosaic. Proper application of EIA/TIA TSB-88 guidelines ensures that the coverage predictions and resulting designs
consider factors including; local environmental noise floor, delivered audio quality, area reliability, subscriber
antenna losses, simulcast TDI performance, voted receiver joint probability improvement.
The figure below depicts an example of land mobile radio coverage modeled using EDX Signal Pro. The color
Green is used to depict areas meeting the minimum coverage parameters for reliability and delivered audio
quality (DAQ). Yellow areas are areas of fringe coverage, which are less reliable and may not provide the
specified DAQ. Areas in white are not covered. Leikhim and Associates believes that the use of colors in
map presentations should be minimized to as few as necessary to convey the best representation of the
coverage attainable instead of presenting a confusing array of threshold gradients.
Within the design of simulcast systems, the influence of Time Domain Interference (TDI) can be problematic in
analog simulcast systems and can adversely affect P25 digital modulation through Inter-Symbol Interference (ISI)
and resulting in degraded bit error rate (BER). TDI effects require optimization of the site locations and geometry,
the antenna patterns, transmitter ERP and in some cases, delay of modulation launch times.
Simulcast analysis
The following figure depicts a typical simulcast analysis employed in the development of a UHF Project 25
simulcast system. In the simulcast analysis, within the coverage contour, areas in white are captured by
one of the three transmitter sites by 16 dB or more, areas in green are served by two or more sites
(not in capture) and the artifacts in shown in red are areas within the coverage border (County line) where
signals from one or more sites are delayed greater than 33 microseconds. Those locations, although receiving
sufficient signal levels, may encounter distortion or failure of the received APCO Project 25 signal.
The exact location of resulting artifacts for a given design will vary somewhat according to the many variables.
The purpose for this analysis is to make the best decision on site locations and other parameters so to attain
the best outcome possible.
Request for Proposal (RFP) Development
In support of the RFP development process, Leikhim and Associates will first develop a detailed Statement of
Work (SOW) reflecting the technology path and detailed design, which meets the requirements of the system
users.
The SOW may take many forms, and depending upon client requirements, can be simplistic and present a
set of needs and solutions to be proposed by vendors through the RFP process, or may be very detailed and
specific, leaving the RFP vehicle to provide vendors only enough latitude to make minor substitutions.
The intent is to provide a balanced procurement process that will encourage competitive and fair response
by multiple qualified bidders.
In the case of a highly complex radio system, the SOW will likely be very specific and detailed in areas of
performance specifications, functional and coverage testing and be less specific in areas where potential
vendors may differ in approach. In no case should performance or other specifications be selected which
unfairly exclude a bidder. In the case where many transmitter sites are required, the RFP will suggest
transmitter sites known to meet the basic coverage objective and try to steer bidders from suggesting
excessive number of “green field” sites, which may be speculative and ultimately infeasible after award.
To ensure delivery of a system meeting the performance objectives of the end users, the testing procedures
should be included in the RFP to establish the functional (ATP) and coverage performance (CATP)
objectives being sought. Test procedures need to be enforceable under the contract.
The RFP should contain a basic schedule of major events and duration of the project from date of award to
final acceptance. Additionally, critical events affecting schedule such as system cutover requirements should
be defined.
Early in the process, contract “boilerplate” required by the procuring agency will be reviewed for any conflict with
RFP and SOW technical requirements. Should any conflict be noted, we will discuss the conflict with the agency
legal staff so that appropriate adjustments are made. Special care should be taken to ensure that the “order of
precedence of documents' provisions do not place the technical performance specifications and testing procedures
of the RFP behind a vendor’s proposal document which may be intentionally vague. Technology projects should
also include fair and balanced contract provisions for dealing with vendor performance issues.
Proposal/Bid Evaluation
Leikhim and Associates can assist in the evaluation of Vendor proposals to ensure compliance with the technical
requirements of the RFP. A structured process is used to ensure fair and accurate process to determine compliance.
Vendor Negotiations
Once the lowest compliant Vendor has been determined, we can assist with the negotiations to
ensure that the fiscal interests of your agency are maintained.
