Attachment 7 - ASR-8-2026-000580-UPEC_A_Requirements_Specification_REV 4.0 Signed 11.3.25.pdf

FEDERAL AVIATION ADMINISTRATION

NATIONAL AIRWAY SYSTEMS ENGINEERING

AJW-143 AIRPORT RADAR SYSTEMS

ASR Universal Pedestal Electronic Control

ASR-8-2026-000580-A

Project Requirements

Version 4.0 11/03/2025

Antenna Positioning Improvement and UPEC Requirements

Approval Signature

Joshua Gruntmeir Sub-Team Manager, ASR-8/ASR-11 AJW-1433

Date

Revision History

Revision Date Author Revision Description

1.0 10/13/2025 RPK Initial

2.0 10/29/2025 BJC Updated for UPEC

3.0 10/31/2025 RPK Review

4.0 10/3/2025 ARF Grammatic Review

Table of Contents

1 INTRODUCTION

1.1 Scope

1.2 Overview

2 REFERENCE DOCUMENTS

3 ACRONYMS AND DEFINITIONS

4 NON-FUNCTIONAL REQUIREMENTS

4.1 General Requirements ....................................................................... Error! Bookmark not defined.

4.1.1 Human Integration ............................................................................ Error! Bookmark not defined.

4.1.2 Electrical ........................................................................................... Error! Bookmark not defined.

4.2 Detailed Requirements

4.2 .1. Hardware

4.3. Software

Appendix A Test Verification Requirements Traceability Matrix

1 Introduction

The purpose of this document is to specify the subsystem specification for the ASR Antenna Positioning and Universal Pedestal Equipment Control (UPEC) project. Full update to the requirements as explained in this document will be performed when the path forward is fully defined.

1.1 Scope

Studies have identified the azimuth position encoders as nearing obsolescence and in cases no longer meeting the NAS needs. The azimuth position information from the encoders to the ASR Systems are interfaced in the Surge Arrester panels in the three systems this project will address obsolescence issues and the need for a single interface to three different Antenna Control Systems separated by time-based technologies.

1.2 Overview

1.2.1 Azimuth

Changes to the azimuth data must include both configurations of encoders that the ASRs currently use. Systems with ATCBI-5 will have one type of encoder and those with MODE-S will have a different type of encoder. These will also have different connections paths. Those systems with a BI-5 will have the encoder path through the ASR-8 A1 Antenna Junction Box. Those with a MODE-S will not pass through the ASR-8 A1 Junction box. For over 20 years, the MODE-S has been connected to the ASR-8 at 11 facilities, yet the ASR-8 documentation does not address that fact. The ASR-9 Has similar issues with the 12-bit portion of the encoder provided to the primary and the 14-bit provided to the secondary.

A review of advancements made an area of non-contact angle sensing in the last decade shows significant progress has been achieved in the performance aspects of angle sensors, overcoming older challenges due to limitations in certain applications.

Emerging technologies on the sensing and electronics field for the development of high-end angle sensors has been driven by angular position sensing as an essential function in most of the engineered systems associated with automotive, robotics, process, and aircraft.

Important sensing techniques utilized for the angle sensors are based on capacitive, inductive, magneto-resistive, and optical schemes. Signal conditioning circuits, analog or digital, or a combination of, are necessary to derive the best from the sensing elements. In parameters such as range, resolution, linearity, accuracy, sensitivity, power consumption, complexity, cost, manufacturability, precision and reliability; current ASR Radar Systems have fallen behind the technology curve.

When the ASR Systems were fielded, the best angular resolution was achieved and specified by an optical encoder directly coupled to the rotating portion of the antenna without use of gears. Various gear configurations currently exist.

A gear driven encoder is no longer considered accurate/precise at higher resolutions (above 14 bit) so that is not discussed here, however an optical encoder attached to the rotating element can be very accurate and precise.

They are, however, subject to dirt, grime and other mechanical issues that degrade performance.

Modern Radar systems use algorithms that use target hit locations to identify the particular shape of that target. To accomplish that it requires a minimum of 14-bit encoder the precision of which matters.

Inductive incoders use rotating sine and cosine signals that generally will contain phase shifts, dc offsets, and distortions. To obtain a reliable position from these sine and cosine signals, a phase demodulation algorithm is generally used on a internal or external circuit board. Incorporating a linearization technique that makes use of the linear sections of the original sinusoidal signals, and the generated phase-shift signals to obtain a linearized signal with some errors. Then, a compensation strategy is introduced to achieve a nearly perfect linearized signal, from which position information can be determined with extreme precision. (This system is sometimes called a Resolver)

1.2.2 Antenna Control and Monitoring

A new NAS requirement to provide Legacy Antenna tower equipment to modern radar systems has been stated. The Three variations of ASR antenna switchgear and towers require control to command rotation and polarization of the existing antennas along with other smaller requirement for system monitoring and maintenance.

2 Reference Documents

Document Name Date

TI 6310.59A

TI 6310.13A

TI 6310.30

3 Acronyms and Definitions

Term Definition

PD Program Directive

FAA Federal Aviation Administration

DOT Department of Transportation

CTD Common Terminal Digitizer

PSF Program Support Facility (PSF)

MMAC Mike Monroney Aeronautical Center

ASR-8 Airport Radar System, Model 8 (FAA nomenclature)

ATCBI-5 Air Traffic Control Beacon Interrogator Model 5

MODE-S Mode Select S

SCM/Harvest Configuration management tool used to control all project documentation

SSM System Support Modification

SDR System Documentation Release

4 Non-Functional Requirements

4.1 General Requirements

4.1.1. Reliability, Maintainability, Availability

• The Azimuth Improvement shall [SYS100] meet or exceed a mean time between failures (MTBF) of 10,000 hours.

• The Azimuth incoder shall [SYS101] be shock resistant, environmentally acceptable for non-radome use and not susceptible to temperature, humidity or other harsh weather conditions.

• The Antenna Control Replacement shall [SYS102] meet or exceed the mean time to repair (MTTR) of 1 hour.

• Local Repair of the Azimuth encoder shall [SYS103] not required and may be accomplished through replacement of the next higher assembly.

4.1.2. Electrical Power Requirements

• The Azimuth and Control Improvement replacement shall

[SYS104] have electrical enclosures, cabling and wiring which are approved by a nationally recognized testing laboratory.

• The Azimuth and Control Improvement replacement shall [SYS105] have the same, or power requirements and characteristics of the Legacy Components it is replacing. (no Major Power Upgrade)

4.1.1 Human Integration

4.1.2 Personnel Safety and Health

• The Azimuth and Control Improvement shall [SYS106] be constructed with safe clearances, workspaces and other safety factors per NFPA Code 70E.

• The Azimuth and Control equipment Improvement design shall [SYS107] provide for personnel safety in accordance with Table 2 of ANSI/IEEE C95.1-1991, Standard for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3kHz to 300 kHz.

• The Azimuth and Control equipment Improvement design shall [SYS108] protect personnel from the harm of moving parts when replacing filters.

• The Azimuth and Control equipment Improvement replacement design shall [SYS109] protect personnel from injury by sharp edges of equipment or cabinets during maintenance. Use of edge guards is required.

• The Azimuth and Control equipment Improvement shall [SYS110] provide a means to protect personnel from accidental contact with voltages in excess of 30Vrms or DC during normal operations or maintenance of the equipment.

• The Azimuth and Control equipment Improvement design shall [SYS111] protect personnel from circuits carrying currents greater than 21mA AC and 80mA DC.

4.2 Detailed Requirements

4.2. Hardware

4.2.1 Dual System Requirement.

4.2.1.1 The azimuth data systems shall [UPEC-111] consist of two azimuth pulse generators, two-line driver pulse amplifiers, two shaper amplifiers, and two separate power supplies.

4.2.1.2 These redundant azimuth data sources shall [UPEC-112] operate independently such that failure of one unit will not interfere with proper operation of the other unit.

4.2.1.3 The generators shall [UPEC-113] be directly coupled to the rotating portion of the antenna without use of gears.

4.2.1.4 Either generator shall [UPEC-114] be removable.

4.2.2 FAA-E-2506, para 3.8.9.2(updated) Reliability of Operation. – The azimuth pulse generation components of the antenna assembly shall [UPEC-115] be designed for continuous and reliable operation.

4.2.2.1 Preventive maintenance, including lubrication and

adjustment, shall [UPEC-116] not be required more frequently than once each 8,000 hours of actual operation.

4.2.2.2 Replacement of parts or overhaul requiring more than one hour of antenna downtime shall [UPEC-117] not be required more frequently than once every five years of actual operation.

4.2.2.3 The number of electronic components located at the

antenna pedestal shall [UPEC-118] be kept to an absolute minimum.

4.2.3 FAA-E-2506, para 3.8.9.3 (updated) Azimuth Pulse Generators. – The azimuth pulse generator shall [UPEC-119] generate a minimum 217 (131072) pulses and one reference pulse for each rotation of the antenna.

4.2.3.1 The 360-degree drift shall [UPEC-120] be 0.73 mili-rads or less.

4.2.3.2 The azimuth reference pulse jitter shall [UPEC-121] be measurable only due to mechanical change in the rate of rotation, or a system mechanical issue external to the APG and is not considered a valid parameter for this upgrade. ARPs shall be monitored by a PLC capable on 50 MHZ clocking or better.

4.2.3.3 The output characteristics of azimuth change pulses and the azimuth reference pulse derived from the antenna pedestal mounted APG shall [UPEC-122] be as follows:

4.2.3.3.1 Azimuth Change Pulses (ACPs): A minimum of a series of 131072 pulses shall [UPEC-123] be generated for each 360-degree rotation of the antenna. Azimuth Pulses may be down converted to facilitate system usage.

4.2.3.3.2 Azimuth Reference Pulse (ARP): A single pulse, shall [UPEC-124] as one ARP, for each 360-degree rotation of the antenna.

4.2.3.3.3 Pulse Amplitude (ACPs and ARP): The pulses shall

[UPEC-125] be at least 3 volts peak on positive-going excursions.

4.2.3.3.4 Output Isolation: Isolation between ACP and ARP signals, including hum and noise, shall [UPEC-126] not be less than 40 dB.

4.2.3.3.4.1 The APG shall [UPEC-127] employ an inductive

pulse with electrical feedback to generate pulse output.

4.2.3.3.4.2 A suitable cable for transmitting the APG signals between the antenna-mounted APG shall [UPEC-128] have the termination point in the Pedestal Equipment Control Replacement Panel in Radar building.

4.2.3.3.4.3 The cable type shall [UPEC-129] be suited to the

physical and electrical environment in which the cable will be installed, of an impedance to match both the APG output and the termination in the building.

4.2.3.3.4.4 The cable type shall [UPEC-130] result in ACP

and ARP signals of the characteristics listed herein for any cable length up to 250 feet.

4.2.4 The azimuth pulse shall [UPEC-131] indicate by pulse count the angular position of the center of the radar beam as determined by the position of the rotating portion of the antenna pedestal, with an angular error not to exceed ±0.0022º.

4.2.4.1 Provisions shall [UPEC-132] be made for setting the

ARP to any angle with respect to the antenna electronically.

4.2.5 Remote/Local Control. - Shall [UPEC -133]. A

"Maintenance/Operate" switch shall be provided at the local site for local control of the antenna function. The function of this switch is to transfer complete control to the local site. The maintenance control shall prevent selection of the antenna rotation or polarization from the remote site;

conversely, operation of the maintenance switch shall have no effect on the antenna. System in maintenance status shall be controlled by controls located on the front panel.

4.2.6 Control signal characteristics. - The radar system control circuit design shall [UPEC -134] employ ground signals or open circuit signals as specified herein to accomplish all system control and readback functions. Each control and readback function shall have a spare isolated single pole double throw (SPDT) switching capability associated therewith and the multiple switch points shall be terminated on the cabinet terminal strips.

4.2.7 Control functions. - A control function shall be initiated by applying a ground signal to the appropriate control connection.

A momentary ground is defined as a signal having a duration equal to or greater than 0.01 second. The maximum current that shall be allowed to flow during the ground signal shall be 100 milliamperes for the legacy Transmitters. The maximum open circuit voltage that can appear on any control function connection point shall be limited to 24 volts and it shall be a positive DC voltage. A control function Shall [UPEC -135]. control a readback function only on an indirect basis as a result of an executed control function.

4.2.8 Readback function. - A readback function Shall [UPEC -136], automatically be initiated as a result of a control being initiated and executed or by some other specified automatic function such as a system alarm interlock, and may be at a 5vdc signal level.

4.2.9 Common system controls. Common system controls Shall [UPEC - 137] be provided for the following functions:

1. Control Antenna rotation On and Antenna rotation Off.

2. Provide switching for Antenna Polarization CP and Antenna

Polarization LP

3. Individual Motor On/Off Function when in Maintenance mode.

4.2.10 The Following radar system alarms/status conditions Shall [UPEC -138] be monitored, reported, logically controllable/ resettable /actionable and the UPEC control system may create a log of each occurrence:

1. Antenna Motor A & B Alarms

2. Pedestal High & Low Oil limit Alarms

3. CHA & CHB Brake Alarms and Maintenance status

4. Main Power Over/under Voltage

5. Antenna interlocks.

4.2.11 The UPEC Shall [UPEC -139] be modernized to interface with the next generation of radar systems.

4.2.12 Readback function. - A readback function shall [UPEC-140] automatically by the Antenna controller be initiated as a result of a control being initiated and executed or by some other specified automatic function such as a system alarm, interlock, etc. A readback function is a ground, 5V or 24V signal applied to the appropriate readback function connection and its duration shall be controlled by the duration of the status of the function being monitored. The readback function signal switching circuit shall be rated to handle 3 amperes at 24 volts DC. The maximum open circuit voltage that can appear on any readback control function connection point shall be limited to 24 volts, and it shall be a positive DC voltage. All energized readback functions shall appear on the front of the panel. The following readback and control functions shall apply:

[UPEC 141] – Provide Control to turn on or off the antenna manually or automatically.

[UPEC 142] -Provide Control to set the condition of the antenna polarization.

[UPEC 143] – Monitor the operation of the antenna and antenna components [UPEC 144] – The overall equipment design shall be such as to minimize Maintenance and installation.

[UPEC 145] – The interface sufficiently connects to the ASR-8. ASR-9 and ASR-11 to provide digital monitoring of the condition of the Antenna switch gear and components.

[UPEC 146] – The UPEC interfaces to external radar systems for antenna control and to provide RF shut off signaling.

4.3. Software

4.3.1 Software shall [UPEC-147] meet all FAA security and

development standards. Additional software requirements may be added during project completion if a higher level of granularity is required for specific software testing.

Appendix A Test Verification Requirements Traceability Matrix

Req. ID Requirement Description Test

Methodolo gy

I=Inspection D=Demonstra tion T=Test

A=Analysis <blank> = N/A

D ev el op m en t

O pe ra tio na l

Sa fe ty

Se cu rit y

K ey

S ite

SYS100

The Azimuth Improvement meet or exceed a mean time between failures (MTBF) of 10,000 hours.

A

SYS101

The Azimuth incoder shall be shock resistant, environmentally acceptable for non-radome use and not susceptible to temperature ,humidity or other harsh weather conditions

A

SYS102

The UPEC Control Improvement replacement shall meet or exceed a mean time to repair (MTTR) of 1 hour.

A D

SYS103

Local Repair of the Azimuth encoder shall not required and may be accomplished through replacement of the next higher assembly.

SYS104

The Azimuth and Control Improvement replacement shall have electrical enclosures, cabling and wiring which are approved by a nationally recognized testing laboratory.

I

SYS105

The Azimuth and Control Improvement replacement shall have the same, or power requirements and characteristics of the Legacy Components it is replacing.

(no Major Power Upgrade)

SYS106

The Azimuth and Control Improvement shall be constructed with safe clearances, workspaces and other safety factors per NFPA Code 70E

I

SYS107

The Azimuth and Control equipment Improvement design shall provide for personnel safety in accordance with Table 2 of ANSI/IEEE C95.1-1991, Standard for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3kHz to 300 kHz.

I

SYS108

The Azimuth and Control equipment Improvement design shall protect personnel from the harm of moving parts when replacing.

I

SYS109

The Azimuth and Control equipment Improvement replacement design shall protect personnel from injury by sharp edges of equipment or cabinets during maintenance. Use of edge guards is required

I

SYS110

The Azimuth and Control equipment Improvement shall provide a means to protect personnel from accidental contact with voltages in excess of 30Vrms or DC during normal operations or maintenance of the equipment.

I I

UPEC111

consist of two azimuth pulse generators, two-line driver pulse amplifiers, two shaper amplifiers, and two separate power supplies

I I

UPEC112 operate independently such that failure of one unit will not interfere with proper operation of the other unit

D

UPEC113 directly coupled to the rotating portion of the antenna without use of gears

D

UPEC114 removable D

UPEC115 designed for continuous and reliable operation A

UPEC116 Preventive maintenance not be required more frequently than once each 8,000 hours of actual operation

A

UPEC117 Replacement of parts or overhaul requiring more than one hour of antenna downtime

A

UPEC118 electronic components located at the antenna pedestal be kept to an absolute minimum

I

UPEC119 generate a minimum 217 (131072) pulses and one reference pulse for each rotation

A

UPEC120 360-degree drift T

UPEC121 pulse jitter T

UPEC122 output characteristics of azimuth change pulses and the azimuth reference pulse

T

UPEC123 minimum of a series of 131072 pulses T

UPEC124 one ARP, for each 360-degree rotation of the antenna T

UPEC125 at least 3 volts peak on positive-going excursions T

UPEC126 Isolation between ACP and ARP signals T

UPEC127 employ an inductive pulse with electrical feedback to generate pulse output

T

UPEC128 suitable cable for transmitting the APG signals between the antenna-mounted APG

T

UPEC129 be suited to the physical and electrical environment in which the cable will be installed

A

UPEC130 cable length up to 250 feet T

UPEC131 indicate by pulse count the angular position of the center of the radar beam

T

UPEC132 setting the ARP to any angle T

UPEC133 "Maintenance/Operate" switch shall be provided T

UPEC134 employ ground signals or open circuit signals as specified T

UPEC135

A control function shall control a readback function only on an indirect basis as a result of an executed control function

T

UPEC136 A readback function shall automatically be initiated for antenna interlock

T

UPEC137 Common system controls Rotation/Polarization T

UPEC138 Alarm/Status monitoring T

UPEC139 Modernized to interface with the next generation of radar systems.

T

UPEC140 Readback function is automatic and Control the Radar building alarm

T

UPEC141 Provide Control to turn on or off the antenna manually or automatically.

T

UPEC142 Provide Control to set the condition of the antenna polarization

T

UPEC143 Monitor the operation of the antenna T

UPEC144 Minimize Maintenance and installation. T

UPEC145 The interface sufficiently connects to ASR-8. ASR-9 and

ASR-11

T

UPEC146 Interfaces to external radar systems T

UPEC147 meet all FAA security and development standards T

Detailed Requirements will be added to this table after initial peer review. Changes, additions, deletion from evaluated comments will become part of the document and this table,

SYS106