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NEXCOM V3 Radio June 15, 2022 V 1.5 i

DEPARTMENT OF TRANSPORTATION

FEDERAL AVIATION ADMINISTRATION

PRODUCT DESCRIPTION (PD)

NEXCOM V3

ULTRA HIGH FREQUENCY (UHF) RECEIVERS AND TRANSMITTERS

VERY HIGH FREQUENCY (VHF) RECEIVERS AND TRANSMITTERS

Air/Ground Voice Communications (AGVC) Team, AJM-313

DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited.

ii

RECORD OF CHANGES

Revision Data Actions

0.0 10/16/2020 Initial DRAFT issue, non-baselined

0.1 10/22/2020 Changed file name and title page from NEXCOM III to NEXCOM V3, inserted 3.4.2.1.c and updated the related Note 1; updated wording of 3.5.2.2.b

0.2 10/27/2020 Updated Section 2.0, updated table references. Oct 2020 RFI edition.

0.3 09/17/2021 Initial incorporation of Market Survey feedback.

0.4 09/22/2021 Incorporates comments following FAA ZOOM review sessions held on 9/21 and 9/22. Appendix C – Statistics Section deletion is accepted.

0.5 10/20/2021 Updated 3.2.1.4 Firmware, Processor, Software Upload and Switchover Requirements. Updated Paragraphs in 3.2.3 – moving important content from previous Appendix C. Appendix C deleted.

Inclusion of a single table for SNMPv3 Management Information Base

(MIB).

0.6 11/18/2021 Incorporates changes from a ZOOM session with Second Level Engineering on 11/16/2021.

0.7 11/22/2021 Incorporates changes from actions on 11/16/2021. Edition used to brief Test Team on 11/22/2021 and 11/23/2021.

0.8 12/01/2021 Incorporates changes from Zoom Sessions held on 11/22/2021 and 11/23/2021, along with FAA action items responses from 11/24/2021.

0.9 12/03/2021 Incorporates changes from FAA reviews regarding updating Section

2.0 references on 12/2/2021.

1.0 12/07/2021 Incorporates formatting updates. Dec 2021 RFI edition.

1.1 5/23/2022 Incorporates feedback from March 2022 Market Survey Vendor One-on-One Meetings. Edition used to brief VoIP SMEs on 5/23/2022.

1.2 5/24/2022 Incorporates formatting updates.

1.3 5/26/2022 Incorporates feedback from March 2022 Market Survey Vendor One-on-One Meetings. Edition used to brief Test Team on 5/27/2022 and 6/2/2022.

1.4 6/8/2022 Incorporates feedback from Test and VoIP Team meetings held on 5/27/2022, 6/2/2022 and 6/7/2022.

1.5 6/15/2022 Incorporates feedback from Test and VoIP Team joint reviews of the v1.4 Edition. June 2022 Edition for SAM.gov.

iii

TABLE OF CONTENTS

1 SCOPE

1.1 Identification

1.2 System Overview

2 APPLICABLE DOCUMENTS

2.1 Government Documents

Specification Standards Other Government Documents

2.2 Non-Government Documents

2.3 Document Sources

FAA Documents Military and Federal Documents OSHA Documents FCC Documents NTIA Documents IEEE/ANSI Documents EIA Documents EIA Documents EUROCAE Documents

IEC Documents IETF Documents NFPA Documents

3 REQUIREMENTS

3.1 Definitions

“Shall” “Should” “Will”

3.2 Radio Requirements

Radio Functions and Software Requirements

3.2.1.1 Modes of Operation

3.2.1.2 Tuning Ranges

3.2.1.3 DSB-AM Modulation Method

3.2.1.4 Firmware, Processor, Software Upload and Switchover Requirements

3.2.1.5 Radio Service Recovery

Performance Requirements

3.2.2.1 Receiver Requirements

3.2.2.2 Transmitter Requirements

Radio Monitoring, Control and Reporting

3.2.3.1 Radio Monitoring, Control and Reporting via an MDT

3.2.3.2 Radio Monitoring and Control via the Radio Front Panel Interface

3.2.3.3 Radio Real-Time Monitoring and Reporting

3.2.3.4 Vendor Built-in Test (BIT)

Internet Protocol (IP) Requirements

3.2.4.1 Remote IP Interface

3.2.4.2 Local IP Interface

iv

3.2.4.3 IP Interface Standards

3.2.4.4 IP Interface Configuration

3.3 Interfaces

Radio Interfaces

3.3.1.1 Radio Frequency (RF) Connectors

3.3.1.2 FILTER IN Connector

3.3.1.3 FILTER OUT Connector

3.3.1.4 Transmitter ATRC Connector

3.3.1.5 Transmitter ATR1 Connector

3.3.1.6 Transmitter ATR2 Connector

3.3.1.7 Electrical Input Power Connectors

3.3.1.8 Receiver Remote Interface Connector

3.3.1.9 Transmitter Remote Interface Connector

3.3.1.10 Transmitter Local Microphone Connector

3.3.1.11 Receiver Local Headset Connector

Additional Connectors

3.3.2.1 Reference Frequency Monitor Connector

3.4 Construction Requirements

Physical Requirements

3.4.1.1 Workmanship

3.4.1.2 Equipment Size

3.4.1.3 Equipment Weight

3.4.1.4 Nameplates

3.4.1.5 Radio Installation/Removal

3.4.1.6 Radio Set-Up

3.4.1.7 Thermal Protection

3.4.1.8 Shock and Vibration Protection

3.4.1.9 Grounding, Bonding, and Shielding

3.4.1.10 Acoustical Noise Criteria Requirement

3.4.1.11 Materials, Processes, and Parts

3.4.1.12 Safety

3.4.1.13 Human Performance/Human Engineering

3.4.1.14 Removable Parts, Mating Connectors, and Interface Cables

3.4.1.15 Test Points

3.4.1.16 Controls

3.4.1.17 Radio Identification (ID) Numbering

Electrical Requirements

3.4.2.1 Input Power Requirements

3.4.2.2 Power Cords

3.4.2.3 Reverse Polarity Protection

3.4.2.4 Circuit Protection

3.4.2.5 Loss of Input Voltage

Environmental Conditions

3.4.3.1 Thermal Design Requirements

3.4.3.2 Operating Conditions

3.4.3.3 Non-Operating Conditions

v

Electromagnetic Compatibility Requirements FCC Equipment Certification

3.5 Quality Factors

Reliability

3.5.1.1 Mean Time Between Failures

Maintainability

3.5.2.1 Mean Time To Repair

3.5.2.2 Periodic Maintenance

Service Life

4 QUALITY ASSURANCE PROVISIONS

4.1 Testing Conditions

Receiver Test Signals and Conditions

4.1.1.1 Test Signal Sources

4.1.1.2 Rated Desired Signal

4.1.1.3 Standard Desired Signal

4.1.1.4 Standard Undesired Signal

4.1.1.5 Squelch Condition For Test

4.1.1.6 Rated Audio Output Power

4.1.1.7 Standard Audio Output Power

4.1.1.8 Rated Audio Band

4.1.1.9 Audio AGC Condition For Test

Transmitter Test Signals and Conditions

4.1.2.1 Coaxial Termination

4.1.2.2 Signal Sources

4.1.2.3 Standard Test Signal

4.1.2.4 Rated Output Power

Test Frequencies Normal Load

4.2 Tests

Electromagnetic Compatibility Tests

4.3 Verification Methods and Verification Requirements Traceability Matrix (VRTM) .67

4.4 Reliability Modeling and Prediction Data

5 PREPARATION FOR DELIVERY

6 APPLICABLE DEFINITIONS

6.1 Very High Frequency (VHF)

6.2 Ultra High Frequency (UHF)

6.3 Mean Time Between Failures (MTBF)

6.4 Mean Time To Repair (MTTR)

6.5 Duty Cycle

6.6 Modular Construction

6.7 Line Replaceable Unit (LRU)

6.8 Adjacent Channel Emissions

6.9 Transmitter Spectral Mask

6.10 Antenna Transfer Relay (ATR) Function

6.11 Factory Reset

6.12 Warm Reset

vi

6.13 Service Restoral

6.14 Non-Volatile Memory

6.15 Equipment Failure

Non-critical Equipment Failure Critical Equipment Failure

6.16 Configuration of Chaining Multiple Radios to a Common Antenna Using the ATR .71

6.17 Equipment Size

6.18 Local(ly)

6.19 Remote(ly)

6.20 Push-to-Talk (PTT)

6.21 Maintenance Data Terminal (MDT)

6.22 MDT Software (MDTS)

6.23 Interface

6.24 Degraded Performance

LIST OF TABLES

Table 3-1: Transmitter Nominal Radio Frequency Output Power Configurations Table 3-2: Tuning Ranges Table 3-3: Receiver Selectivity Profile Table 3-4: Receiver Spurious Frequency Rejection Undesired Signal Table 3-5: Receiver Intermodulation Undesired Signals Table 3-6: Receiver Audio Frequency Response Audio Bands Table 3-7: Receiver Collocation Cases Table 3-8: Receiver Rejection of Signals Outside the Band Undesired Signal Cases Table 3-9: Receiver Automatic Gain Control (AGC) Stabilization Undesired Signal Table 3-10: Transmitter Audio Input Signal Ranges Table 3-11: Transmitter RF Output Power Ranges Table 3-12: Transmitter Back Intermodulation Cases Table 3-13: Transmitter Adjacent Channel Power Mask Table 3-14: Adjustable Voltage Keying Threshold Table 3-15: Typical Minimum MDT Hardware/Software Table 3-16: FAA Compulsory Monitoring and Control Parameters Table 3-17: ED-137C/5 ANNEX A3 MIB and FAA Desired MIB Details Table 3-18: FAA Desired Monitoring and Control Parameters Table 3-19: Receiver Remote Interface Connector Table 3-20: Transmitter Remote Interface Connector Table 3-21: Radio Functions and Labeling Table 3-22: Maximum Current Limits Table 3-23: Operating Conditions Table 3-24: Non-Operating Conditions Table 4-1: Rated Audio Bands Table 4-2: Test Channels vii

LIST OF FIGURES

Figure 3.1: Illustration of Normal, Alert, and Alarm Range for a Parameter Figure 6.1: Transmitter Spectral Mask Figure 6.2: Conceptual Illustration of Internal Filter/Antenna Transfer Relay Configuration ... 70 Figure 6.3: Conceptual Illustration of Transceiver Configuration Figure 6.4: Conceptual Illustration of Transmitter Main/Standby Configuration Figure 6.5: Rack Unit Definitions

LIST OF APPENDICES

APPENDIX A: List of Abbreviations......................................................................................... A-1 APPENDIX B: Verification Requirements Traceability Matrix (VRTM) ................................. B-1

1 SCOPE

1.1 Identification

This document contains the Product Description (PD) for the NEXt generation Air/Ground (A/G) COMmunications (NEXCOM) Version 3 (V3) System Ultra High Frequency (UHF) and Very High Frequency (VHF) Radios. This NEXCOM V3 Radio PD describes the functions and performance requirements necessary for the radio equipment to satisfy the NEXCOM V3 Radio deployment. All requirements in this PD are common to both the UHF and VHF radios unless the requirement specifically addresses a particular radio.

1.2 System Overview

The Federal Aviation Administration (FAA) requires A/G voice communications links to provide Air Traffic Control (ATC) services to all classes of National Airspace System (NAS) users. These links support all phases of flight including en route, terminal approach control, flight service and terminal space-based ground movements; departures and arrivals. The UHF/VHF radios are used to ensure aircraft separation, transmit instructions and clearances, permit hand-offs, provide weather services and pilot reports (PIREPs), and communicate with Automated Flight Service Stations (AFSSs). Civilian aircraft, including air carrier and general aviation, are served in the VHF band while Department of Defense (DOD) aircraft are served in the UHF band.

The NEXCOM V3 Radio Program will replace current UHF/VHF ground-based analog radios at Remote Center Air/Ground (RCAG) and Back-Up Emergency Communications (BUEC) facilities supporting en route Communications.

NEXCOM V3 Radios will operate using the current 25 kHz channel-spacing assignment in the UHF and VHF radio frequency (RF) bands. Both RF bands will support signal-in-space communications using a double sideband-amplitude modulation (DSB-AM) waveform. The VHF radios will also have frequency tuning capabilities to operate on 8.33 kHz channel-spacing assignments in accordance with International Civil Aviation Organization (ICAO) defined standards.

NEXCOM V3 radios will be physically compatible with today’s existing NAS equipment, will be equipped with a legacy analog audio interface(s) as well as an ED-137C/1 compliant Internet Protocol (IP)-based audio interface(s) supporting future NAS gateway subsystems and components.

2 APPLICABLE DOCUMENTS

The following documents form a part of this NEXCOM V3 Radio PD. Each document is applicable in full unless specified herein. The version of each identified document that is in effect at the time of vendor proposal receipt for the FAA is applicable, unless explicitly noted. In case of conflict between the documents referenced and the contents of this PD, the contents of this PD shall take precedence.

2.1 Government Documents

Specification

FAA: Federal Aviation Administration FAA-G-2100J Electronic Equipment, General Requirements.. April 2022.

Standards

FAA-STD-019E Lightning and Surge Protection, Grounding, Bonding and

Shielding Requirements for Facilities and Electronic Equipment.

December 2005.

FAA-STD-025F Preparation of Interface Documentation. November 2007.

HF-STD-001B Human Factors Design Standard (HFDS). December 2016.

Military:

MIL-STD-461G Requirements For The Control Of Electromagnetic Interference Characteristics of Subsystems and Equipment. December 2015.

MIL-STD-810H Department of Defense Test Method Standard. January 2019.

MIL-STD-889D Galvanic Compatibility of Electrically Conductive Materials.

July 2021.

MIL-HDBK-454C General Guidelines for Electronic Equipment. September 2021.

MIL-HDBK-217F

Change Notice 2

Reliability Prediction of Electronic Equipment. February 1995.

OSHA: Occupational Safety and Health Administration 29 CFR Part 1910 Occupational Safety and Health Standards: Subpart S, Electrical.

Other Government Documents

FAA Order

JO 6580.3

Remote Communications Facilities Installation Standards Handbook.

FCC: Federal Communications Commission 47 CFR Part 2 Frequency Allocations and Radio Treaty Matters; General Rules and Regulations. October 2015.

FCC: Federal Communications Commission 47 CFR Part 15 Radio Frequency Devices. October 2015.

47 CFR Part 87 Aviation Services. October 2015.

NTIA: National Telecommunications and Information Administration Redbook Manual of Regulations and Procedures for Federal Radio

Frequency Management. September 2017.

2.2 Non-Government Documents

IEEE/ANSI: Institute of Electrical and Electronics Engineers/ American National Standards Institute

802.3-2018 IEEE Standard for Information Technology – Telecommunications and Information Exchange between Systems – Local and Metropolitan area Networks – Specific Requirements, Part 3: Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method and Physical Layer Specifications. August 2018.

C62.36-2016 IEEE Standard Test Methods for Surge Protectors and Protective Circuits Used in Information and Communications Technology (ICT) Circuits, and Smart Grid Data Circuits. May 2016.

C62.41.2-2002 IEEE Recommended Practice on Characterization of Surges in Low Voltage (1000 V and Less) AC Power Circuits. 2002. (The FAA is researching alternatives to this document)

C62.45-2002 IEEE Recommended Practice on Surge Testing for Equipment Connected to Low-Voltage (1000 V and Less) AC Power Circuits. 2002. (The FAA is researching alternatives to this document)

EIA: Electronic Industries Alliance EIA/ECA-310-E Cabinets, Racks, Panels, and Associated Equipment.

December 2005.

ETSI: European Telecommunications Standards Institute

EN-300-676-1

(V1.5.2)

Ground-based VHF Hand-Held, Mobile and Fixed Radio Transmitters, Receivers and Transceivers for the VHF Aeronautical Mobile Service Using Amplitude Modulation; Part 1: Technical Characteristics and Methods of Measurement.

March 2011

EUROCAE: European Organisation for Civil Aviation Equipment ED-136 Voice Over Internet Protocol (VoIP) Air Traffic Management

(ATM) System Operational and Technical Requirements.

February 2009

ED-137C/1 Interoperability Standards for VoIP ATM Components, Volume 1 Radio. April 2017

ED-137C/1,

Change 1

Interoperability Standards for VoIP ATM Components, Volume 1 Radio, Change 1. May 2020

ED-137C/4 Interoperability Standards for VoIP ATM Components, Volume 4 Recording. March 2019

ED-137C/4,

Change 1

Interoperability Standards for VoIP ATM Components, Volume 4 Recording, Change 1. May 2020

ED-137C/5 Interoperability Standard for VoIP ATM Components, Volume 5 Supervision. April 2019

IEC: International Electrotechnical Commission

IEC 60320-1

Ed.4.0 b

Appliance Couplers for Household and Similar General Purposes

– Part 1: General Requirements. 2021.

IEC 61000-3-2 Electromagnetic compatibility (EMC) - Part 3-2: Limits - Limits for harmonic current emissions (equipment input current <= 16 A per phase) Edition: 2.0

IETF: Internet Engineering Task Force RFC-791 Internet Protocol. September 1981.

RFC-1213 Management Information Base for Network Management of TCP/IP-based internets: MIB II. March 1991.

RFC-2460 Internet Protocol, Version 6 (IPv6) Specification.

December 1998.

RFC-2816 A Framework for Integrated Services Over Shared and Switched IEEE 802 LAN Technologies. May 2000.

RFC-3411 An Architect For Describing Simple Network Management Protocol (SNMP) Management Frameworks. December 2002.

NFPA: National Fire Protection Association NFPA 70 National Electric Code. 2020.

2.3 Document Sources

FAA Documents

Copies of FAA specifications, standards, and publications may be obtained from the NEXCOM Contracting Officer, FAA, 800 Independence Avenue SW, Washington, DC 20591. Requests will clearly identify the desired material by number and state the intended use of the material.

The following documents are available for download from FAA Web pages and/or everyspec.com:

FAA-G-2100

https://my.faa.gov/org/linebusiness/ato/operations/facilities_engineering/power_services/ sys_eng_team/stand_specs.html/

HF-STD-001

http://hf.tc.faa.gov/hfds/

FAA-STD-019 and FAA-STD-025 http://everyspec.com/FAA/FAA-STD/

Military and Federal Documents

Single copies of unclassified military and federal specifications, standards, and publications may be obtained by writing the Naval Publications and Forms Center, 5801 Tabor Avenue, Philadelphia, PA 19120, or by calling (215) 697-3321 Monday through Friday, 8:00 a.m. to 4:30 p.m. Eastern Standard Time (EST). The following Department of Defense Web site offers military publications for download: http://quicksearch.dla.mil/.

The following Web page offers guidance in identifying, locating, or acquiring U.S. military publications and documents: http://www.loc.gov/rr/news/someplaces.html.

OSHA Documents

Copies of Occupational Safety & Health Administration (OSHA) documents may be obtained from the U.S. Department of Labor Occupational Safety & Health Administration, 200 Constitution Avenue, Washington, DC 20210. A copy of 29 CFR 1910 may be obtained from the following Web site at https://www.osha.gov/laws-regs/regulations/standardnumber/1910.

FCC Documents

Copies of 47 CFR, Part 2, Part 15 and Part 87 may be obtained from the Federal Communications Commission (FCC), 445 12th Street SW, Washington, DC 20554, or downloaded from the Web at http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&tpl=/ecfrbrowse/Title47/47cfrv1_02.tpl.

NTIA Documents

Copies of National Telecommunications and Information Administration (NTIA) materials may be obtained from NTIA, Department of Commerce, 14th Street and Constitution Avenue NW, Washington, DC 20230, or through the NTIA Web site at http://www.ntia.doc.gov. The Manual of Regulations and Procedures for Federal Radio Frequency Management, September 2017

Edition is available for download at https://www.ntia.doc.gov/page/2011/manual-regulations-and-procedures-federal-radio-frequency-management-redbook.

IEEE/ANSI Documents

Copies of Institute of Electrical and Electronics Engineers (IEEE) documents may be requested as follows: by mail at IEEE Customer Service, 445 Hoes Lane, Piscataway, NJ 08854-4141; by phone (800) 701-4333 (in the United States and Canada) or (732) 981-0060 (outside the United States and Canada); or via the following Web site: https://www.ieee.org/publications/index.html.

The American National Standards Institute (ANSI) Web site is located at http://www.ansi.org.

EIA Documents

Copies of Electronic Industries Alliance (EIA) standards may be obtained from https://global.ihs.com/standards.cfm?publisher=ECIA.

EIA Documents

Copies of European Telecommunications Standards Institute (ETSI) documents may be obtained from the ETSI Secretariat at F-06921 Sophia Antipolis CEDEX, France, or from the ETSI Web site at https://www.etsi.org/index.php/standards#Pre-defined%20Collections.

EUROCAE Documents

ED-137C Interoperability Standards for VoIP ATM Components, Volume 1 Radio requirements and its related Change 1 requirements, as applicable, are collectively referred to as ED-137C/1 hereafter. ED-137C Interoperability Standards for VoIP ATM Components, Volume 4 Recording requirements and its related Change 1 requirements, as applicable, are collectively referred to as ED-137C/4 hereafter. ED-137C Interoperability Standards for VoIP ATM Components, Volume 5 Supervision requirements is referred to as ED-137C/5 hereafter. EUROCAE documents can be purchased via the Web at https://eshop.eurocae.net.

IEC Documents

International Electrotechnical Commission (IEC) publications are available for purchase via the Web at http://www.iec.ch.

IETF Documents

IETF documents are available for download from http://www.rfc-editor.org/rfc.html.

NFPA Documents

Copies of National Fire Protection Association (NFPA) documents may be obtained from NFPA, 1 Batterymarch Park, Quincy, MA 02169-7471. A copy of NFPA 70, National Electrical Code, may be purchased from the NFPA Web site at http://www.nfpa.org/aboutthecodes/AboutTheCodes.asp?DocNum=70&cookie%5Ftest=1.

3 REQUIREMENTS

3.1 Definitions

“Shall”

When used in this PD, the word “shall” refers to a compulsory requirement of a system-component, parameter or the complete system.

“Should”

When used in this PD, the word “should” refers to a desired, but not a compulsory, requirement of a system-component, parameter or the complete system.

“Will”

When used in this PD, the word “will” provides information for a characteristic of a system-component or a complete related system.

3.2 Radio Requirements

The technical characteristics described in this PD are for ground based VHF and UHF radio equipment and, unless otherwise specified, apply to both the receiver and transmitter equipment.

A receiver or a transmitter is considered to be a Line Replaceable Unit (LRU).

a) The radio equipment shall be implemented as individual UHF and VHF radios or as multiband UHF/VHF radios1.

b) The radio equipment shall be implemented as individual receivers and transmitters, i.e., no transceivers will be considered.

c) The transmitter(s) shall be implemented as either individual low power and high power configurations,1,3 or as an extended power transmitter configuration,1,2,3 as defined in Table 3-1 and Table 3-11.

d) The UHF high power transmitter,1,2,3 or UHF extended power transmitter,1,2,3 should be implemented as defined by the desired operational output power function in Table 3-1 and Table 3-11.

e) If implemented, an extended power transmitter configuration,1,2,3 shall have a control parameter for configuring low power or high power modes as defined in Table 3-16.

f) If implemented, an extended power transmitter configuration,1,2,3 shall have a control parameter for configuring a RF Output Power Level Low Threshold as defined in ED- 137C/5 ANNEX A3 Management Information Base (MIB).

g) If implemented, an extended power transmitter configuration,1,2,3 shall have a control parameter for configuring a RF Output Power Level High Threshold as defined in ED-

137C/5 ANNEX A3 MIB.

h) The VHF transmitter(s) shall have a control parameter for adjusting the CLIMAX Offset as defined in ED-137C/5 ANNEX A3 MIB.

i) The VHF transmitter(s) should have a control parameter with the CLIMAX Offset default setting as defined in Table 3-17.

j) The radio equipment shall be implemented such that each individual radio has its own power supply.

k) All radio requirements shall be met under all operational modes, conditions, and over the frequency range(s) specified in this PD.1,2,3

Note 1: Multiband radios can be used to fulfill the VHF band or UHF band requirements; however, it is expected that all compulsory equipment size and ratios requirements defined in section 3.4.1.2 will be met.

Note 2: All requirements within this PD apply to the respective transmit power configuration of an extended power transmitter unless otherwise stated, i.e., when the extended power transmitter is configured as a low power transmitter it is expected to perform the same as if it were an individual low power transmitter and when configured as a high power transmitter it is expected to perform the same as if it were an individual high power transmitter.

Note 3: The transmitter radio frequency (RF) output power level in Table 3-1 below defines the nominal power measured at the Antenna Transfer Relay (ATR) output port and accounts for losses incurred through the ATR and in-line cavity filter. These values apply to individual low and high power transmitters or the extended power transmitter configured for the relevant power mode. See section 3.2.2.2.5 and Table 3-11 for additional details.

Table 3-1: Transmitter Nominal Radio Frequency Output Power Configurations Frequency

Band Low Power Transmitter (W)

High Power Transmitter (W)

Extended Power Transmitter (W)

VHF 2 to 12 12 to 35 2 to 35

UHF 2 to 12 12 to 35 or (12 to 50)*

2 to 35 or (2 to 50)*

* Desired operational function

Radio Functions and Software Requirements

3.2.1.1 Modes of Operation

a) The radio equipment shall operate in DSB-AM (see section 3.2.1.3) using 25 kHz channel spacing.

b) The VHF radio equipment shall operate in DSB-AM using 8.33 kHz channel spacing.

c) The VHF radio equipment shall be user configurable to allow the equipment to operate in either 25 kHz DSB-AM or 8.33 kHz DSB-AM channel spacing.

d) The VHF radio equipment, when configured for 8.33 kHz channel spacing, shall operate in compliance with ETSI specification EN-300-6761 (excluding ETSI sections 4.3 and 5).

Note 1: If a requirement in this PD conflicts with a requirement in ETSI specification EN-300-676, the requirement of this PD will take precedence.

3.2.1.2 Tuning Ranges

a) The radio equipment shall be capable of tuning and operating at all frequencies within the relevant band as defined in Table 3-2.

b) The radio equipment shall have a control parameter for configuring all frequencies within the relevant band as defined in ED-137C/5 ANNEX A3 MIB (i.e., Nominal Frequency or Current Frequency).

c) The radio equipment should have a control parameter with default settings for UHF and VHF frequencies as defined in Table 3-17.

d) The radio equipment shall have a control parameter for channel spacing within the VHF band as defined in ED-137C/5 ANNEX A3 MIB (i.e., Frequency Spacing or Channel Spacing).

e) The radio equipment should have a control parameter with a default setting for VHF channel spacing as defined in Table 3-17.

f) The radio equipment should have a control parameter for tuning the Lowest Tunable Frequency, within the VHF band, as defined in Table 3-18.

g) The radio equipment should have a control parameter for tuning the Highest Tunable Frequency, within the VHF band, as defined in Table 3-18.

Table 3-2: Tuning Ranges VHF (MHz) UHF (MHz)

25 kHz Channel Spacing

8.33 kHz Channel Spacing

25 kHz Channel Spacing

112.000 to 150.000 112.000 to 150.000 225.000 to 399.975

3.2.1.3 DSB-AM Modulation Method

a) The radio modulation method shall be A3E DSB-AM in accordance with FCC regulations in 47 CFR, Part 2, Frequency Allocations and Radio Treaty Matters; General Rules and Regulations, October 2015; Part 87, Aviation Services, October 2015; and the NTIA Manual of Regulations and Procedures for Federal Radio Frequency Management, September 2017.

3.2.1.4 Firmware, Processor, Software Upload and Switchover Requirements

a) The radio equipment shall be software/firmware (SWFW) upgradeable.

b) The radio equipment shall allow local and remote radio SWFW uploads.

c) The radio equipment, as separate entities, shall use no more than 50 percent of their non-volatile memory (as defined in section 6.14, Non-Volatile Memory) for storage under worst-case conditions (e.g., when a radio has SWFW active (in-use) and other SWFW version(s) is/are loaded).

d) The radio equipment, as separate entities, shall use no more than 50 percent of their random-access memory (RAM), under worst-case conditions (e.g., when a radio has the SWFW active (in-use) and other SWFW version(s) is/are loaded).

e) The peak utilization of the available resources of each processor within receivers and transmitters, inclusive of Digital Signal Processors (DSPs) and Field Programmable Gate Arrays (FPGAs), shall not exceed 50% when placed under its maximum usage1.

f) The radio equipment shall support a configurable number of concurrent Session Initiation Protocol (SIP) sessions.

g) The radio equipment shall support a minimum of 7 concurrent SIP sessions.

h) The radio equipment shall have an internal clock for event logging.

i) Any new radio SWFW upload shall not overwrite the designated active radio SWFW version.

j) The switchover to the new uploaded radio SWFW version shall only occur upon receipt of a manual radio SWFW switchover command.

k) All existing and current radio settings shall be retained during a radio SWFW switchover process.

l) Any new settings introduced in a new radio SWFW version, meaning not present in a previous radio SWFW version, shall take their default setting after the radio SWFW switchover process.

m) During the radio SWFW switchover process, the new uploaded radio SWFW version shall become the active radio SWFW version, while the prior active SWFW version becomes the previous SWFW version.

n) The radio SWFW switchover process shall prevent transmitters from switching to a SWFW version intended for a receiver.

o) The radio SWFW switchover process shall prevent receivers from switching to a SWFW version intended for a transmitter.

p) If a switchover to the new radio SWFW version is unsuccessful or rejected, the radio shall revert to, or remain with, the previous version of the radio SWFW, perform a Warm Reset, if needed, and return to the last operational state.

q) The time to perform a switchover between SWFW versions within the radio equipment should be 3 minutes or less.

Note 1: The maximum usage is defined as the maximum load on the radios’ processors when handling maximum number of SIP/RTP sessions, at least 1 SNMPv3 session and 1 recording session (if the recording interface is present).

3.2.1.5 Radio Service Recovery

3.2.1.5.1 Automatic Radio Service Recovery

a) The radio equipment shall automatically recover from AC and DC power interruptions.

b) The radio equipment shall resume operational services after recovery from AC and DC power interruptions.

c) The radio equipment shall automatically restore operational service using the radio’s monitoring and control parameter settings that were in effect prior to the electrical power service disruption.

3.2.1.5.2 User Invoked Radio Service Recovery

a) The radio equipment shall have a Factory Reset, as defined in section 6.11, that is user-invoked via the front panel interface (see section 3.2.3.2.1).

b) The radio equipment shall have a control parameter for a Warm Reset as defined in Table 3-16 and in section 6.12.

3.2.1.5.3 Radio Service Recovery Restoral Time

a) The receiver shall detect the presence of any RF signal at the antenna port, break squelch, demodulate, and process and present audio to the respective audio interface ports, or be ready to respond to VoIP protocol handshaking requests using a static IP address, within 6 seconds of power reactivation1 from a facility service restoral.

b) The transmitter shall re-accept any analog (discrete) push-to-talk (PTT) key from a respective PTT key interface, process any analog audio stream, and modulate an analog stream onto an RF carrier for transmission at the antenna port within 6 seconds of power reactivation1 from a facility service restoral, or be ready to respond to VoIP protocol handshaking requests using a static IP address within 6 seconds of power reactivation1 from a facility service restoral.

Note 1: Power reactivation from a facility service restoral (i.e., restoral of AC and/or DC after the loss or interruption of both AC and DC) corresponds to the radio boot time after a cold start (i.e. switch on of the radio).

Performance Requirements

3.2.2.1 Receiver Requirements

All receiver performance requirements will be validated using standard test signals and test frequencies as described in sections 4.1.1 and 4.1.3 of this PD unless otherwise stated.

3.2.2.1.1 Receiver Audio Interfaces

a) The receiver shall provide a remote1 analog audio output at the receiver remote interface connector (see section 3.3.1.8).

b) The receiver remote analog audio level shall be controllable via the Maintenance Data Terminal (MDT).

c) The receiver remote analog audio level shall be controllable via the front panel interface (see section 3.2.3.2.1).

d) The receiver shall provide a local analog audio output to be used with a headset/headphone (see section 3.3.1.11).

e) The local1 analog audio output level shall be independently controllable from the front panel via a control knob or the front panel interface (if implemented).

f) The receiver shall have a speaker on the front panel utilizing the local analog audio circuit.

g) The receiver speaker should be disabled when the headset/headphone plug is inserted into the local audio output.

h) The remote analog audio output shall have a balanced 600 ohm (±10 percent) output impedance.

i) The local analog audio output shall provide audio levels of sufficient amplitude, to allow for monitoring of voice traffic, when terminated with headphone impedances in the range of 30 to 600 ohms.

j) The receiver shall be capable of sending VoIP audio data via the remote Internet Protocol (IP) interface (see section 3.2.4.3).

k) The receiver internal audio delay shall not exceed 20 ms as measured between the envelope of the modulated RF signal applied to the antenna input and the demodulated audio available at the analog audio outputs and the remote IP interface via VoIP.

Note 1: The terms local(ly) and remote(ly) are defined in sections 6.18 and 6.19, respectively.

Note 2: The receiver’s internal audio delay requirement is not to be misconstrued with the user-selectable voice packet size lengths supporting Voice Communications System (VCS) to Ground Radio Station (GRS) communications. VCS-to-GRS communicate using voice packets with sizes of 10ms, 20ms, and 30ms; with the default setting of 20ms.

Note 3: For verification of the receiver’s internal audio delay requirement, when in VoIP mode, the radio packetization delay will be excluded from the data measurement. Refer to Figure 11, Voice Delay Requirements (Ground Components), of ED-136, VoIP ATM System Operation and Technical Requirements.

3.2.2.1.2 Receiver Sensitivity

a) The receiver RF input shall have 50 ohm normal load1 characteristic impedance.

b) The receiver shall produce a SINAD of 10 dB or greater at the remote audio output when a standard desired signal of no more than −102 dBm is present at the receiver RF input2.

Note 1: The term normal load is defined in section 4.1.4.

Note 2: A desired signal of -102 dBm is herein defined as the rated desired signal (see section 4.1.1.2). SINAD is defined as the ratio of (Signal plus Noise plus Distortion) to (Noise plus Distortion).

3.2.2.1.3 Receiver Rejection of Signals Inside the Operating Bands

See section 3.2.2.1.17.

3.2.2.1.4 Receiver Selectivity

a) The selectivity of the receiver shall conform to Table 3-3 with respect to the tuned channel center frequency across the entire frequency band.

Table 3-3: Receiver Selectivity Profile

Case Level DSB-AM Bandwidth

(25 kHz Channel Spacing) DSB-AM Bandwidth

(8.33 kHz Channel Spacing)

A1,2 −6.0 dB 9 kHz Minimum 3.5 kHz Minimum B1,2 −60.0 dB 25 kHz Maximum 8.33 kHz Maximum C1 −80.0 dB 50 kHz Maximum 25 kHz Maximum

Note 1: VHF receivers are required to meet all the conditions in Cases A, B, and C.

Note 2: UHF receivers are required to meet the conditions in Cases A and B for 25 kHz channel spacing.

3.2.2.1.5 Receiver Spurious Frequency Rejection

a) The VHF receiver should not have image frequencies within the 112.000 MHz to

150.000 MHz band.

b) The UHF receiver should not have image frequencies within the 225.000 MHz to

399.975 MHz frequency band.

c) The sensitivity requirements of section 3.2.2.1.2 shall not be degraded by more than 3 dB in the presence of an undesired signal as specified in Table 3-4 for the relevant receiver type.

Table 3-4: Receiver Spurious Frequency Rejection Undesired Signal Frequency

Band Undesired

Modulation Undesired Signal

Level (dBm) Undesired Frequencies

VHF CW* −12

Any image frequency within the

112.000 MHz to 150.000 MHz band

VHF CW* −22

Any image frequency outside the

112.000 MHz to 150.000 MHz band;

and, All spurious response frequencies up to 1 GHz1

UHF CW* −32

Any image frequency; and, All spurious response frequencies up to 1 GHz1

* Continuous Wave

Note 1: Collocation testing will not be conducted where the frequency of the interfering signal is coincidental with a known spurious response frequency.

3.2.2.1.6 Receiver Distortion

3.2.2.1.6.1 Receiver Intermodulation

a) The sensitivity requirements defined in section 3.2.2.1.2 shall not be degraded by more than 3 dB in the presence of two undesired signals as defined in Case A of Table 3-5, with frequencies chosen such that one of the 3rd order products is located on the receiver operating frequency.

b) The sensitivity requirements defined in section 3.2.2.1.2 shall not be degraded by more than 3 dB in the presence of two undesired signals as defined in Case B of Table 3-5, with frequencies chosen such that one of the 3rd order products is located on the receiver operating frequency.

c) The sensitivity requirements defined in section 3.2.2.1.2 shall not be degraded by more than 3 dB in the presence of two undesired signals as defined in Case C of Table 3-5, with the frequencies of the undesired signals offset from the receiver operating frequency by +2.0 MHz and +4.0 MHz, or –2.0 MHz and –4.0 MHz, respectively.

d) The sensitivity requirements defined in section 3.2.2.1.2 shall not be degraded by more than 3 dB in the presence of two undesired signals as defined in Case D of Table 3-5, with frequencies chosen such that the 2nd order products are located on the chosen UHF receiver operating frequency.

Table 3-5: Receiver Intermodulation Undesired Signals

Case Undesired Signal

#1 Modulation Undesired Signal

#2 Modulation

Undesired Signal Levels

(dBm)

Undesired Frequency

Band (MHz)

A1 FM, 404 Hz tone with 75 kHz Deviation

FM - 404 Hz tone with 75 kHz Deviation

−5 87.5 to 107.9

B1 FM, 404 Hz tone with 75 kHz Deviation

CW +5 87.5 to 107.9

C1 DSB-AM, 404 Hz tone at 90%

DSB-AM – 404 Hz tone at 90% −30 Operating Band

D2 DSB-AM, 404 Hz tone at 30%

CW +5

118.000 to

136.975

Note 1: VHF and UHF receivers are required to meet Cases A through C.

Note 2: UHF receivers are required to meet Case D.

3.2.2.1.6.2 Receiver Cross Modulation

a) The sensitivity requirements defined in section 3.2.2.1.2 shall not be degraded by more than 2 dB in the presence of a standard undesired signal separated by ±0.5 MHz and at a level 70.0 dB above the rated desired signal.

b) The sensitivity requirements defined in section 3.2.2.1.2 shall not be degraded by more than 2 dB in the presence of a standard undesired signal separated by ±1.0 MHz and at a level 75.0 dB above the rated desired signal.

c) The sensitivity requirements defined in section 3.2.2.1.2 shall not be degraded by more than 2 dB in the presence of a standard undesired signal separated by ±1.5 MHz and at a level 80.0 dB above the rated desired signal.

Note: A standard undesired signal is defined in section 4.1.1.4.

3.2.2.1.7 Receiver Frequency Tolerance

a) The frequency tolerance of the receiver reference frequency shall be within 0.0001 percent (1 ppm) of its reference value for a period of one year following alignment over the full frequency range specified in section 3.2.1.2, and the temperature range specified in section 3.4.3.2 (Operating Conditions).

b) The reference used to generate the receiver operating frequency shall have a tuning adjustment to compensate for aging during the minimum useful service life1 of the equipment.

c) The receiver operating frequency shall be adjustable to within 1 ppm of the tuned channel center frequency.

d) If a measurement of the receiver frequency reference is required to align the radio to meet the tolerance defined in 3.2.2.1.7.a, the external reference frequency monitor port shall have an impedance of 50 ohms.

e) If a measurement of the receiver frequency reference is required to align the radio to meet the tolerance defined in 3.2.2.1.7.a, the external reference frequency monitor port shall have a reference signal level greater than or equal to −20 dBm.

f) If a measurement of the receiver frequency reference is required to align the radio to meet the tolerance defined in 3.2.2.1.7.a, the receiver shall provide an output of the reference frequency signal for measurement, testing and alignment.

g) If a measurement of the receiver frequency reference is required to align the radio to meet the tolerance defined in 3.2.2.1.7.a, the reference signal monitor port shall be sufficiently isolated such that a short circuit applied from the monitor port to ground does not degrade the radio performance as specified in section 3.2.2.1, Receiver Requirements.

Note 1: The minimum useful service life is defined in section 3.5.3.

3.2.2.1.8 Receiver Audio Output Control

a) The remote audio output level of the receiver shall be adjustable in the range between −25 dBm (−0/+1 dB) and +10 dBm (−0/+2 dB) in the presence of a standard desired signal.

b) The remote audio output level of the receiver shall be adjustable in 0.5 dB steps or less.

c) The remote audio output level of the receiver should be adjustable in 0.25 dB steps or less.

d) The receiver shall have a control parameter for adjusting the remote audio output level as defined in Table 3-16.

e) The receiver should have a control parameter for adjusting the remote audio output level as defined in Table 3-18.

f) The local audio output level1 of the receiver shall be adjustable in the range between

−25 dBm (−0/+1 dB) and +10 dBm (−0/+2 dB) in the presence of a standard desired signal.

g) The local audio output level1 of the receiver should be adjustable in 0.5 dB steps or less.

Note 1: Receiver local audio interfaces are defined in section 3.2.2.1.1.

3.2.2.1.9 Receiver Audio Level Regulation

a) The remote audio output level of the receiver (adjusted for rated audio output power) shall not vary more than ±1.0 dB as a standard desired signal's modulation is increased from 30 to 100 percent.

b) The remote audio output level of the receiver (adjusted for rated audio output power) shall not drop more than 4.0 dB when the load resistance is reduced from 600 to 120 ohms.

Note: The rated audio output power is defined in section 4.1.1.6.

3.2.2.1.10 Receiver Audio Automatic Level Stabilization

a) The remote audio output level of the receiver (adjusted for standard audio output power) shall not vary by more than ±3 dB from a reference audio level for any standard desired signal between −98 dBm and −7 dBm.

Note: The reference audio level is measured with a −50 dBm standard desired signal. The standard audio output is defined in section 4.1.1.7.

3.2.2.1.11 Receiver Audio Mute and Attenuation

a) The receiver should have a discrete analog input for muting the receiver remote audio output.

b) The receiver mute function should have a control parameter to be enabled or disabled as defined in Table 3-18.

c) The receiver should have a control parameter for muting the receiver remote audio output as defined in Table 3-18.

d) The receiver muting function attenuation level should be selectable with the following values: −15 dB, −20 dB, or no audio (i.e., “no audio” is defined as at least 70 dB down from a reference level of +10 dBm).

e) The tolerances for the -15 dB and -20 dB selectable attenuation should be ±2 dB.

f) The default for the selectable attenuation should be no audio.

g) The receiver should have a control parameter for selecting the muting function attenuation level as defined in Table 3-18.

h) The muting signal should have an attack time no greater than 10 ms.

i) The receiver audio should be muted when either the control parameter or the input from the receiver remote interface indicate audio muting, and unmute when both indicate no mute.

j) The receiver should provide a confirmation signal via the receiver remote interface for the duration of the mute.

3.2.2.1.12 Receiver Average Audio Output

a) The remote audio output level of the receiver (adjusted for standard audio output power using a reference desired signal) shall be −13 dBm (±2 dB) averaged over 3 seconds in the presence of a −87 dBm signal, AM modulated at 90 percent using a Government furnished speech sample.

b) The peak remote audio output level of the receiver (adjusted for standard audio output power using a reference desired signal) shall not exceed 0 dBm in the presence of a −87 dBm signal, AM modulated at 90 percent using a Government furnished speech sample.

Note: The reference desired signal is defined as a −87 dBm carrier, amplitude modulated with a 1004 Hz sine wave to a depth of 30 percent. The Government furnished speech samples were made available prior to release of the final Screening Information Request (SIR).

3.2.2.1.13 Receiver Audio Distortion

a) The remote audio output shall not be distorted by more than 2.0 percent in the presence of a standard desired signal for 30 percent modulation with any RF input level between −67 dBm and −27 dBm, for any input tones within the rated audio band for the relevant channel spacing configuration.

b) The remote audio output shall not be distorted by more than 5.0 percent for 90 percent modulation with any RF input level between −67 dBm and −27 dBm, for any input tones within the rated audio band for the relevant channel spacing configuration.

Note: The rated audio band is defined in section 4.1.1.8.

3.2.2.1.14 Receiver Audio Frequency Response

a) The remote audio output level shall not vary by more than ±2.0 dB from the level achieved with a reference desired signal (see note) when the reference audio input frequency is varied within the rated audio band.

b) The remote audio output level shall decrease monotonically from the level achieved with a reference desired signal as the frequency increases between the ranges indicated by the high frequency rejection band in Table 3-6.

c) The remote audio output level shall be at least 20.0 dB down from the level achieved with a reference desired signal at frequencies indicated by the ultimate frequency rejection band of Table 3-6.

d) The remote audio output level shall decrease monotonically from the level achieved with a reference desired signal as the audio frequency decreases between the ranges indicated in the low frequency rejection band of Table 3-6 and be down at least 10.0 dB at 100 Hz.

Note: The reference desired signal is defined as a -102 dBm to -7 dBm carrier, amplitude modulated with a 1004 Hz tone to a depth of 90 percent.

Table 3-6: Receiver Audio Frequency Response Audio Bands

Channel Spacing (kHz)

Low Frequency Rejection Band

(Hz)

Audio Pass Band (Hz)

High Frequency Rejection Band

(Hz)

Ultimate Frequency

Rejection Band (Hz)

25 0 to 300 300 to 3000 3000 to 10000 10000+

8.33 0 to 350 350 to 2500 2500 to 10000 10000+

3.2.2.1.15 Receiver Squelch

3.2.2.1.15.1 Squelch

a) The receiver shall have a squelch system consisting of both an RF level threshold (herein defined as carrier squelch) and an audio signal-to-noise threshold (herein defined as noise squelch).

b) The receiver audio output level shall be at least 70 dB down from a reference level of +10 dBm when the receiver is set for squelch-enabled condition and in the presence of an input RF signal level less than the squelch RF threshold level.

c) The receiver remote audio level transients shall be 20.0 dB below the audio alignment level under any operating condition or configuration with the alignment level ranging between −25 dBm to +10 dBm.

d) The receiver shall have a monitoring parameter for squelch break status as defined in Table 3-16.

e) The receiver squelch function shall, at a minimum, have a control parameter to select squelch function states: off (1), carrierOnly (2) and snOnly (3), as defined in ED-137C/5 ANNEX A3 MIB (i.e., Status of the Squelch Function).

f) The receiver squelch function should have a control parameter with the FAA-desired squelch state default setting and squelch state option: snAndCarrier, as defined in Table 3-17 (i.e., Status of the Squelch Function).

3.2.2.1.15.2 Receiver Squelch Adjustment, Sensitivity, and Hysteresis

a) If implemented, such that both the Audio Signal-to-Noise (S/N) Squelch function and RF Carrier Squelch function are enabled (i.e., snAndCarrier), then the receiver remote and local audio shall be enabled when the received signal exceeds both the RF Carrier Threshold and the Audio S/N Threshold values defined in b) and e) below.

b) The receiver Audio S/N Squelch Threshold value shall be adjustable in 1 dB steps or less in the range of +6 dB to +20 dB in the presence of a DSB-AM signal modulated 30 percent with a 1004 Hz tone.

c) The receiver Audio (S/N) Squelch Threshold function shall have a control parameter to adjust the S/N Threshold value as defined in ED-137C/5 ANNEX A3 MIB.

d) The receiver Audio (S/N) Squelch Threshold function should have a control parameter with the S/N Threshold default setting as defined in Table 3-17.

e) The RF Carrier Squelch Threshold level shall be adjustable in 1 dB steps or less in the power range from –102 dBm to –70 dBm.

f) The RF Carrier Squelch closing hysteresis shall be not less than 2 dB and not greater than 7 dB with respect to the receiver Carrier Squelch Threshold value.

g) The RF Carrier Squelch Threshold function shall have a control parameter to adjust the RF Carrier Threshold value as defined in ED-137C/5 ANNEX A3 MIB.

h) The RF Carrier Squelch Threshold function should have a control parameter with the RF Carrier Threshold default setting as defined in Table 3-17.

i) If the Audio S/N Squelch function is enabled and the RF Carrier Squelch function is disabled (i.e., snOnly), then the receiver remote and local audio shall be enabled when the received signal exceeds the audio signal-to-noise ratio threshold value defined in b) of this section.

j) If the RF Carrier Squelch function is enabled and the Audio S/N Squelch function is disabled (i.e., carrierOnly), then the receiver remote and local audio shall be enabled when the received signal exceeds the RF carrier power threshold value defined in e) of this section.

3.2.2.1.15.3 Receiver Squelch Attack and Release Times

a) The squelch attack time shall not exceed 30 ms with any standard desired signal with an RF level between −102 dBm and −7 dBm.

b) The squelch attack time should not exceed 20 ms with any standard desired signal with an RF level between −102 dBm and −7 dBm.

c) The squelch release time shall not exceed 35 ms.

Note: For verification of these requirements, the receiver internal audio delay value, up to the limit defined in section 3.2.2.1.1.k, will be subtracted from the raw squelch attack and release time measurements.

3.2.2.1.16 Collocation

a) The…

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