Using TSB-88 Region 5 700 MHz

1
Using TSB-88 Region 5 700 MHz

• Using TSB-88 to insure frequency usage does not
  cause interference in Region 5

2
TSB-88 Purpose

• Accommodating the design and frequency
  coordination of bandwidth efficient narrowband
  technologies likely to be deployed as a result of
  the Federal Communications Commission "Spectrum
  Refarming efforts
• Assessing and quantifying the impact of new
  narrowband/bandwidth efficient digital and analog
  technologies on existing analog and digital
  technologies
• Assessing and quantifying the impact of existing
  analog and digital technologies on new
  narrowband/bandwidth efficient digital and analog
  technologies
• Addressing migration and spectrum management
  issues involved in the transition to
  narrowband/bandwidth efficient digital and analog
  technologies. This includes developing solutions
  to the spectrum management and frequency
  coordination issues resulting from the narrow
  banding of existing spectrum considering channel
  spacing from 30 and 25 kHz to 15, 12.5, 7.5, and
  6.25 kHz
• Information on new and emerging Land Mobile bands
  such as the 700, 800 and 900 MHz bands
• Preliminary information on narrowband wideband
  data, 25, 50, 100 and 150 kHz channel bandwidths
  and
• Address the methodology of minimizing intra
  system interference between current or proposed
  Noise Limited Systems in spectral and spatial
  proximity to Interference Limited Systems.

3
TSB -88 Guidance

• Establishment of standardized methodology for
  modeling and simulating narrowband/bandwidth
  efficient technologies operating in a post
  "Refarming" environment
• Recommended databases and propagation models that
  are available for improved results from modeling
  and simulation
• Establishment of a standardized methodology for
  empirically confirming the performance of
  narrowband/bandwidth efficient systems operating
  in a post "Refarming" environment or in new
  frequency band allocations, and
• Combining the modeling, simulation and empirical
  performance verification methods into a unified
  family of data sets or procedures which can be
  employed by frequency coordinators, systems
  engineers, system operators or software developers

4
Some Terms

• Channel Performance Criterion (CPC) The maximum
  BER at a specified vehicular Doppler rate
  necessary to deliver a specific DAQ for the
  specific modulation. The recommended CPC form is
  Cf/N or Cf/(IN) _at_ X Hz Doppler.
• Confidence Interval A statistical term where a
  confidence level is stated for the probability of
  the true value of something being within a given
  range which is the interval.
• Confidence Level also called Confidence
  Coefficient or Degree of Confidence, the
  probability that the true value lies within the
  Confidence Interval.
• CPC Service Area Reliability The CPC Service
  Area Reliability is the probability of achieving
  the desired DAQ over the defined Service Area.
• DAQ The acronym for Delivered Audio Quality, a
  reference similar to Circuit Merit with
  additional definitions for digitized voice and a
  static SINAD equivalent intelligibility when
  subjected to multipath fading.

5
Some More Terms

• Equivalent Noise Bandwidth (ENBW) The frequency
  span of an ideal filter whose area equals the
  area under the actual power transfer function
  curve and whose gain equals the peak gain of the
  actual power transfer function. In many cases,
  this value could be close to the 3- dB bandwidth.
  However, there exist situations where the use of
  the 3- dB bandwidth can lead to erroneous
  results. Sometimes ENBW is referred to as
  Effective Noise Bandwidth.
• Interference Limited The case where the CPC is
  dominated by the Interference component of
  C/(IN).
• Noise Limited The case where the CPC is
  dominated by the Noise component of C/(IN).
• Service Area The specific users geographic
  bounded area of concern. Usually a political
  boundary such as a city line, county limit or
  similar definition for the users business. Can be
  defined relative to site coordinates or an
  irregular polygon where points are defined by
  latitude and longitude. In some Public Safety
  systems the Service Area could be greater than
  their Jurisdictional Area. This is done to
  facilitate interference mitigation or allow
  simulcasting without violating regulatory contour
  regulations.

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So What Do We Want To Do?

• Given an existing system(s) and a new proposed
  site(s), we desire to protect all parties from
  harmful interference
• The systems will work in an interference limited
  environment

7
How Do We Do That?

• We first define a minimum signal median signal
  level for all service areas
• Given the system modulation type, we determine a
  maximum interfering mean signal level that the
  system can tolerate in the service area
• More specifically, we determine from TSB-88 Annex
  A the desired to undesired signal ratio in db
  needed to protect the system

8
Noise Limited Operation
-105.9 dBm DAQ 3.4 level
17.7 dB
-116 dBm Reference Sensitivity
7.6 dB
Noise Floor -123.6 dBm
9
Interference Limited

• To get better reuse we work with interference
  limited operations.
• Therefore coverage area needs minimum 40 dBu
  throughout the coverage area
• Interference must be at least the VCPC value for
  3.4 DAQ

10
ComStudy Parameters

• Longley/Rice Median (50) values plus defaults
  on other parameters
• Map Sized to show co and adjacent channel users
  service areas
• No additional land use attenuation
• Set Transmit Box parameters to Interference,
  Equivalent, Selected, T out, 40.0 MinFS, 3.4 DAQ,
  and Map limited
• For each existing Site, in turn, select the new
  site and existing site and select Vfor the
  existing site . Click redraw label and print
  the map.

11
For First in Agencies

• If there are no existing co-channel users then
• Produce map using Longley/Rice 50 values and
  default values
• Use colors to show 40 and 20 dBu tiles
• Remember it is your responsibility to design your
  coverage to a minimum of 40 dBu in your service
  area and to minimize to the extent possible, the
  signal levels outside your service area
• Be prepared to show how you used directional
  antennas, low level sites and terrain shielding
  to minimize signal level outside of your coverage
  area