TLS Operational Description

0786-EX-PL-2013 Text Documents

Advanced Navigation & Positioning Corp.

2014-01-02ELS_144352

         TRANSPONDER LANDING SYSTEM
             SYSTEMS DESCRIPTION




                                                      _
                                                     ANPC
                          ADVANCED NAVIGATION & POSITIONING CORPORATION




                                            May 12, 2006




                                   ANPC Confidential and Proprietary
              This document is UNCONTROLLED after it is printed. Verify Currency prior to use
Page 2 of 7


TPLT—05001 Rev A Ver 0.1                   Rev. A TLS SDS                                          Date
                                     Systems—Level Requirements




                           © Advanced Navigation and Positioning Corporation, 2006
                                            All Rights Reserved
                                   11 Third Street, Hood River, OR 97031




                                ANPC Confidential and Proprietary
           This document is UNCONTROLLED after it is printed. Verify Currency prior to use
                                                                                             Page 3 of 7


                                                  TABLE OF CONTENTS

SECTION 1: INTRODUCTION 1.2.0222022200002022298 46e t vvvirerressressirssveererissstr ce ersserer iess ssrrssvreerr es ce rr se ee4 5
   1.1 PUFDOS@....22.022222200000rrrvvervrrvrsverrerreserverescversersererssrsevesrrrserrsrrsrsrsrsrrssrererrsrserrrrscrrrrersererrerrarrereeee 5
   esWe 5
SECTION 2: TRANSPONDER LANDING SYSTEM (TLS) OVERVIEW ....,,2222......0006e es 6
   2.1 FUNCtIONAIIEY .....2222200002222020e e e rv es ra e vevrrrvarv e rssakvevsrsas se vrrv is as se se ersaveverssserrer e iss es es aaker ie iss ki e e en ne 6
      PAlareteOe 6
      peMmieZ enE‘w 6
   2.2 BASIC TLS OP@ANION .......0220020200060eereevsversvevvcevevereerssecr¢erssssve@vecc@rercassevervres es se rsaarsrer se c aaa k64 7




                                       ANPC Confidential and Proprietary
                  This document is UNCONTROLLED after it is printed. Verify Currency prior to use
Page 4 of 7


      TPLT—05001 Rev A Ver 0.1                 Rev. A TLS SDS                                           Date
                                         Systems—Level Requirements




      SECTION 1: INTRODUCTION

1.1   Purpose
      This document is to support an application for an FCC Experimental Radio License for the TLS
      engineering site at The Dalles Airport. ANPC has maintained an STA (callsign WAIXGD) for
      the installation since 1999. The intent is to transition from the STA process to obtaining an
      experimental license of longer duration.

1.2   Scope
      This document provides the top—level system description for the Transponder Landing System
      (TLS), developed by Advanced Navigation and Positioning Corporation (ANPC) of Hood River,
      Oregon. The goal of the effort is to develop a navigational aid that provides improved all—
      weather access to runways by providing flexible installation requirements and not requiring new
      avionics on the aircraft.

      A TLS implementation description and operational overview is presented in section 2.




                                      ANPC Confidential and Proprietary
                 This document is UNCONTROLLED after it is printed. Verify Currency prior to use
                                                                                                   Page 5 of 7


      SECTION 2: TRANSPONDER LANDING SYSTEM (TLS) OVERVIEW

2.1   Functionality
      Transponder Landing System (TLS) is a precision guided—approach landing system primarily
      servicing aircraft flying terrain—challenged approach paths. TLS incorporates Secondary
      Surveillance Radar (SSR) interrogation schemes to identify and track cooperative aircraft within
      the service volume. To provide guidance to subject aircraft, TLS emulates Instrument Landing
      System (ILS) guidance signals but has more flexible siting criteria than ILS systems. This
      combination of capabilities enables TLS to support precision approach procedures to
      problematic runways without requiring additional equipment on board ILS equipped aircraft.
      From a pilot‘s perspective a TLS approach is similar to an ILS approach except that transponder
      operation with a specific transponder code is required.
      To facilitate acceptance and integration by regulatory bodies, the functions of the TLS guidance
      will be designed to:
         e    Satisfy ICAO signal—in—space requirements for a Category I ILS.
         e    Minimize transponder occupancy to that which provides the necessary track accuracy
              and system availability.

      Tracking
      The TLS can resolve and identify the transponder codes from the synchronous replies. The TLS
      maintains a position track for the transponder codes of interest (the criteria for code selection
      will be described in the operational description below). This position track is used to determine:
          *   the difference in azimuth of the approaching aircraft in reference to the centerline of the
              designed approach course and
          e   the difference in elevation of the approaching aircraft with respect to the desired Glide
              Slope for that approach.
      The system then provides guidance information (equivalent to an ILS Localizer signal and a
      Glide Slope signal) to the aircraft. The guidance information on that uplink channel is only valid
      for the intended aircraft.

      Guidance
      TLS provides:
          e   the means for aircraft transitioning from en—route navigation to final runway approach.
          e   clearance signals for the pilot to complete the localizer and glide slope intercept. A
              clearance signal is defined as a full scale deflection on the CDI outside the proportional
              guidance volume.
          e   precision guidance to CAT | approach minimums.

2.2   Basic TLS Operation
      The operational sequence for establishing track and providing guidance to a landing aircraft is
      as follows. An aircraft operating under Air Traffic Control (ATC) Instrument Flight Rules (IFR)
      procedures intending to make an approach is assigned a transponder identification code. The
                                         ANPC Confidential and Proprietary
                    This document is UNCONTROLLED after it is printed. Verify Currency prior to use
      Page 6 of 7


TPLT—05001 Rev A Ver 0.1                  Rev. A TLS SDS                                          Date
                                    Systems—Level Requirements

TLS system is commanded to search the tracking area for this transponder identification code.
The TLS transmits an interrogation signal which, when received by any transponder in the TLS
service volume, stimulates a reply. At the same time the interrogation signal is broadcast, the
TLS receive sensor arrays will begin a data collection cycle. For a period following the start
pulse, the sensors store the transponder pulse returns from all aircraft in the tracking area,
along with carrier signal measurements that allow aircraft position angles to be computed. The
TLS then searches the pulse returns for the assigned identification code. This interrogation and
search cycle is repeated several times each second.
Note: For TLS Rev. A,      an operator utilizes the Remote Control Unit (RCU) to control the
system.

When the user aircraft enters tracking volume and its identification code begins to show up in
the data from the sensors, the TLS identifies that aircraft as the one to be tracked and starts
computing its position. Range is computed based on the Time—of—Arrival (TOA) of the
transponder reply pulses relative to the start pulse. The azimuth and elevation angles are
determined by the carrier signal phase measurements derived from the Angle—of—Arrival (AOA).
Once confidence criteria on the accuracy of the tracking solution are satisfied, the TLS begins to
transmit guidance corrections based on the aircraft‘s horizontal and vertical offset from the
predefined approach path. Interrogations, position measurements, and guidance transmissions
then continue cyclically several times per second. As long as the aircraft being tracked remains
inside the service volume the cycle is continued until the aircraft reaches the runway approach
threshold or leaves the TLS guidance volume. The TLS then terminates guidance and performs
any required diagnostics. The system will then become available to await a command to search
for the next user aircraft.
The following is a description of the functional steps in system operation after:
After the TLS is initialized and system acquisition has started, the TLS transmits interrogation
pulses (1030 MHz). Any aircraft within the TLS service volume will be capable of receiving this
signal.
The transponder(s) respond to the interrogation signal by sending a pulsed reply at 1090 MHz.
The transponder reply signals are received at the sensors where pulse characteristic
information about the aircraft replies is measured. This data is sent to Base Station computers
where software determines the position of the approaching aircraft.
The TLS determines the displacement from the desired approach path that is stored in the
system and then determines the message content of the Glide Slope and Localizer signals.
The TLS generates the required ILS guidance signals and broadcasts these signals into the
service volume over standard ILS frequencies.




                                  ANPC Confidential and Proprietary
           This document is UNCONTROLLED after it is printed. Verify Currency prior to use
                                                                                             Page 7 of 7


        STEP 1: TLS Interrogates all of the aircraft
                transponders within the service
                volume with mode 3/A request
                (1030 MHz)




                                                                 STEP 2: Aircraft                       z—=" 2e
                                                       l'T': ;           Transponder      ;     |      STEP 3: TLS sensors
                                                                        Responds                *               measure the pulses
                                                                        (1090 MHz)                              of the desired
                                                                                                                transponder reply
                                                                                                                and software
                                                                                                                determines aircraft‘s
                                                                                                                position




         STEP 4: TLS determines the                    $0 OX
                    displacement from the              5/        \
                    desired approach that is                     _
                    stored in the system
                                                                 x;                    STEP 5: TLS calculates the required
      5 "I                             _—                        fi4                             course adjustments and
        x9k ‘EL n          //                                                                   broadcasts a modulated signal
                                                                                                into the service volume over
      /                                                                                         standard ILS frequencies


                                                  Figure 1              TLS Operation




TLS version Rev. — and Rev. A requires a ground—based person, the Remote Control Unit
(RCU) operator, to enter the transponder code of the approaching aircraft. Guidance is only
valid for aircraft transmitting this transponder code. Since the RCU operator is unique to TLS,
special pilot training is required and therefore TLS is a special approach.




                                   ANPC Confidential and Proprietary
              This document is UNCONTROLLED after it is printed. Verify Currency prior to use
Page 8 of 7


                                      Transponder Landing System                                 Date, .
                                                                                                           ~*| Inserted: Date


SECTION 1: INTRODUCTION

Purpose
This paper was prepared to address a request for more information in support of application for a
FCC transmit license for the Transponder Landing System (TLS) installed at the Columbia
Gorge Regional Airport in Dallesport, WA. The purpose of this license application is to
facilitate the development and demonstration of the Transponder Landing System technology.
FCC File Number: 0237—EX—PL—2006
Confirmation Number: EL805454
Reference Number: 4711

Background
Advanced Navigation & Positioning Corporation (ANPC) uses its TLS installation at the
Columbia Gorge Regional Airport for engineering and testing, as well as demonstration. For this
purpose, ANPC has been renewing FCC STA‘s for the site since 1998. Last fall, Don Nellis,
FAA Spectrum Management, recommended that ANPC apply for a license to eliminate the need
to renew the STA every 6 months.

Operational Description
The TLS uses ground based equipment to produce a high accuracy track of aircraft equipped
with Mode A transponders. The TLS can then broadcast ILS—like guidance to provide a
Category I instrument approach for that aircraft.

The system is only interrogating (1030 MHz) and broadcasting VHF and UHF signals once an
approach operation has been initiated. After the approach operation has completed the system
transitions to Standby mode and is idle.




                                   ANPC Confidential and Proprietary
              This document is UNCONTROLLED after it is printed—— Verify Currency prior to use
Page 4 of 6



Document Created: 2018-12-09 19:26:43
Document Modified: 2018-12-09 19:26:43

© 2026 FCC.report
This site is not affiliated with or endorsed by the FCC