MIL-STD-188-165B-C1 DRAFT 23JUN2023.pdf

DEPARTMENT OF DEFENSE

INTERFACE STANDARD

INTEROPERABILITY OF

SUPERHIGH FREQUENCY (SHF) SATELLITE

COMMUNICATIONS

PHASE-SHIFT KEYING (PSK) MODEMS

AMSC N/A AREA TCSS

DISTRIBUTION STATEMENT A. Approved for public release. Distribution is unlimited.

MIL-STD-188-165B

w/CHANGE 1

DRAFT

SUPERSEDING

26 March 2018

NOT MEASUREMENT

SENSITIVE

NOTE: This draft, dated 01 July 2023, prepared by DISA DC1, has not been approved and is subject to modification. DO NOT USE PRIOR TO

APPROVAL. (Project TCSS-2019-006)

DRAFT DATED 01 JULY 2023

ii

FOREWORD

1. This standard is approved for use by all Departments and Agencies of the Department of Defense (DoD) within the distribution limitations noted at the bottom of the cover.

2. It is DoD policy that all joint and combined operations be supported by compatible;

interoperable; and integrated Command, Control, Communications, and Intelligence (C3I) systems. All C3I systems developed for use by U.S. forces are considered to be for joint use.

The Director, Defense Information Systems Agency (DISA), serves as the DoD single point of contact for developing information technology standards to achieve interoperability and compatibility. All C3I systems and equipment shall conform to technical and procedural standards for compatibility and interoperability.

3. Military Standards (MIL-STDs) in the 188 series (MIL-STD-188-XXX) address telecommunications design parameters and are to be used in all new DoD systems and equipment procurements, or major upgrades thereto. The MIL-STD-188 series is subdivided into a MIL-

STD-188-100 series, covering common standards for tactical and long-haul communications; a

MIL-STD-188-200 series, covering standards for tactical communications only; and a MIL-

STD-188-300 series, covering standards for long-haul communications only. Emphasis is being placed on the development of common standards for tactical and long-haul communications (the

MIL-STD-188-100 series). The MIL-STD-188 series may be based on, or make reference to, American National Standards Institute (ANSI) standards, International Telecommunications

Union – Telecommunication (ITU-T) Standardization Sector recommendations, International

Standards Organization (ISO), North Atlantic Treaty Organization (NATO) Standardization

Agreements (STANAGs), and other standards, wherever applicable.

4. This MIL-STD is part of a profile of standards for Super High Frequency (SHF)

Satellite Communications (SATCOM) (6.5).

5. Comments, suggestions, and questions on this document should be addressed to

DISA, 6910 Cooper Ave., ATTN: IE53, Fort Meade, MD 20755-5496, or emailed to henry.h.tran.civ@mail.mil. Because contact information can change, verify the currency of this address information by using the ASSIST Online database at https://assist.dla.mil.

mailto:henry.h.tran.civ@mail.mil https://assist.dla.mil/

DRAFT DATED 01 JULY 2023

iii

CONTENTS

PARAGRAPH PAGE

FOREWORD ............................................................................................................. ii

1 SCOPE

1.1 Scope

1.2 Applicability

1.3 Certification authority

1.4 Additional requirements

1.5 Special Types of Modems

1.6 Requests to deviate from the standard

2 APPLICABLE DOCUMENTS

2.1 General

2.2 Government documents

2.2.1 Specifications, standards, and handbooks

2.2.2 Reports and Studies

2.3 Non-Government publications

2.4 Order of precedence

3 DEFINITIONS

3.1 Definitions of terms

3.2 Abbreviations

3.3 Accuracy

3.4 Acquisition

3.5 Back to back

3.6 Baud

3.7 Bit Error Ratio (BER)

3.8 Chip

3.9 Chip rate (RC)

3.10 Data rate (RD)

3.11 Data synchronization

DRAFT DATED 01 JULY 2023

iv

3.12 dBc

3.13 Eb/N0

3.14 Error Vector Magnitude (EVM)

3.15 ES/N0

3.16 Frequency uncertainty

3.17 Modem emulation

3.18 Punctured code

3.19 Quasi Error Free ES/N0 (QEF ES/N0)

3.20 Reference ES/N0

3.21 Stability

3.22 Symbol rate (RS)

3.23 Threshold Eb/N0

3.24 Threshold ES/N0

4 GENERAL REQUIREMENTS

4.1 Overview

4.2 Modem description

4.2.1 Transmission function

4.2.2 Reception function

4.2.3 Control and monitoring functions

4.3 Operational conditions

4.4 Environmental perturbation

5 DETAILED REQUIREMENTS

5.1 Overview

5.2 Frequency reference

5.3 Baseband interfaces

5.3.1 Data rates

5.3.2 Ethernet data interfaces

5.3.2.1 Ethernet flow control

5.3.2.2 Radio-router signaling

5.3.3 Serial data interfaces

5.3.3.1 High Speed Serial Interface

5.3.3.2 Balanced serial

DRAFT DATED 01 JULY 2023

v

5.3.3.3 Unbalanced serial

5.4 Modem emulations

5.4.1 Continuous wave

5.4.2 OM-73

5.4.3 Legacy MIL-STD-188-165

5.4.4 IESS-308

5.4.5 IESS-309

5.4.6 IESS-310

5.4.7 IESS-315

5.4.8 ETSI EN 301 790 (DVB RCS)

5.4.9 NATO STANAG 4486

5.4.10 ETSI EN 301 790 (DVB-S2)

5.4.11 ETSI EN 302 307–2 (DVB-S2X)

5.4.12 New modem emulations

5.5 IF output interface

5.5.1 IF output frequency bands

5.5.2 Output impedance

5.5.3 IF output carrier

5.5.3.1 IF output carrier frequency

5.5.3.2 IF stability

5.5.3.3 IF accuracy

5.5.3.4 Phase noise

5.5.4 Output power control range, step size, and accuracy

5.5.5 Spectral output

5.5.5.1 Spectral confinement

5.5.5.2 Transmission thermal noise

5.5.5.3 Transmission output spurious emissions

5.5.5.4 Transmission output harmonics

5.5.6 Modulation performance

5.5.6.1 Spectral inversion

5.5.6.2 Error vector magnitude

5.6 IF input interface

DRAFT DATED 01 JULY 2023

vi

5.6.1 IF input frequency bands

5.6.2 Input impedance

5.6.3 IF input carrier

5.6.3.1 IF input carrier frequency

5.6.3.2 Input frequency uncertainty

5.6.4 IF input power

5.6.4.1 Desired carrier

5.6.4.1.1 Minimum operating IF carrier input level

5.6.4.1.2 Maximum operating IF carrier input level

5.6.4.2 IF input overload

5.6.5 Noise Figure

5.7 Demodulation

5.7.1 Demodulation requirements

5.7.2 Acquisition and timing performance requirements

5.7.2.1 Initial acquisition

5.7.2.2 Reacquisition

5.7.2.3 Bit count integrity

5.7.2.4 Synchronization retention

5.7.2.5 Timing jitter

5.7.2.6 Doppler environment

5.7.3 Error performance requirements

5.7.3.1 Back-to-back error performance

5.7.3.1.1 CW modulation format

5.7.3.1.2 Low data rate performance

5.7.3.1.3 OM-73

5.7.3.1.4 Legacy MIL-STD-188-165

5.7.3.1.5 IESS-308

5.7.3.1.6 IESS-309

5.7.3.1.7 IESS-310

5.7.3.1.8 IESS-315

5.7.3.1.9 NATO STANAG 4486

5.7.3.1.10 ETSI EN 301 790 (DVB RCS)

DRAFT DATED 01 JULY 2023

vii

5.7.3.1.11 ETSI EN 301 790 (DVB-S2)

5.7.3.1.12 ETSI EN 302 307–2 (DVB-S2X)

5.7.3.1.13 New modem emulations

5.7.3.2 Error performance with Adjacent Channel Interference (ACI)

5.7.3.2.1 Equal symbol-rate ACI scenarios

5.7.3.2.2 Double symbol rate ACI scenario

5.7.3.2.3 Threshold ES/N0 allowance for ACI

5.7.3.3 Composite power

5.7.3.4 Isolation of integrated modulators and demodulators

5.8 Modem control and monitoring functions

5.8.1 Modem remote control interface

5.8.2 Control and monitoring parameters

5.8.2.1 Control response times

5.8.2.2 Eb/N0 reporting requirements

5.8.3 Positive modem control

6 NOTES

6.1 Intended use

6.2 Acquisition requirements

6.3 Tailoring guidance

6.4 Subject term (keyword) listing

6.5 SHF SATCOM standards profile

6.6 Changes from previous issue

6.7 Change notations

6.8 Background and future guidance

NATO STANAG 4486 BACK-TO-BACK ERROR

PERFORMANCE

Scope

Turbo code mode

MULTIPLE CARRIER MODEMS

Scope

Multi-carrier modem requirements application

Multi-carrier modem test guidance

DRAFT DATED 01 JULY 2023

viii

MULTIPLE FREQUENCY – TIME DIVISION MULTIPLE

ACCESS (MF-TDMA)

Scope

Ethernet traffic management

Spectral confinement

FREQUENCY HOPPING SPREAD SPECTRUM (FHSS)

Scope

Spectral confinement

DIRECT SEQUENCE SPREAD SPECTRUM (DSSS)

Scope

DSSS requirements application

ESD masks and terminal certification

ESD definition for standard waveforms

DSSS spread factor

ESD reduction using DSSS

Numerical example

DSSS procurement considerations

E.8.1 Code Division Multiple Access (CDMA)

E.8.2 Derivation of minimum required spread factor SF

CONCLUDING MATERIAL

DRAFT DATED 01 JULY 2023

ix

FIGURES

FIGURE 1. Modem functional overview FIGURE 2. Transmitted IF phase noise mask examples

FIGURE 3. Transmission carrier output OFF thresholds FIGURE 4. Modulator output signal spectral density limit mask FIGURE 5. Equal symbol rate ACI FIGURE 6. Double symbol rate ACI FIGURE 7. ACI implementation loss allowances

FIGURE 8. Composite power thresholds FIGURE 9. SHF SATCOM standards profile

TABLES

TABLE I. FEC punctured code patterns

TABLE II. QPSK and OQPSK symbol mapping TABLE III. BPSK, QPSK, and OQPSK punctured code patterns

TABLE IV. Transmitted IF phase noise threshold examples TABLE V. Acquisition times for selected symbol rates TABLE VI. Doppler parameters

TABLE VII. Modem control and monitoring parameters TABLE VIII. Background and Future Guidance

TABLE A-I. NATO STANAG 4486 BPSK, QPSK, and OQPSK Performance TABLE A-II. NATO STANAG 4486 8-PSK Performance

TABLE A-III. NATO STANAG 4486 16-ary Performance TABLE E-I. Minimum spread factor values required to support various network sizes

DRAFT DATED 01 JULY 2023

1 SCOPE

1.1 Scope. This standard covers Phase-Shift Keying (PSK) modems. The requirements specified herein represent the minimum performance specifications required for interoperability; the requirements may be exceeded by equipment developers to satisfy specific service requirements. Thus, incorporating additional standard and nonstandard capabilities and interfaces is not precluded.

1.2 Applicability. The interface and performance specifications contained herein apply to satellite modems used to communicate through transponders on the Defense Satellite

Communications System (DSCS) and the Wideband Global SATCOM (WGS) system. The military-unique requirements for Super High Frequency (SHF) SATCOM modems that operate over X-band and Military Ka-band apply when the modem is used to provide access to the DoD

Information Networks (DoDIN).

1.3 Certification authority. The U.S. Space Force (USSF) Delta 8 SATCOM is the certification authority for the WGS and DSCS communications system and may be contacted at the following address.

Delta 8 SATCOM

Consolidated Wideband SATCOM System Expert (C-SSE)

350 Vandenberg Street

Peterson Space Force Base, CO 80914-2749 widebandengineering@groups.af.mil

1.4 Additional requirements. Delta 8 SATCOM may levy certification requirements in addition to those listed herein. Modem designers/vendors shall coordinate with the certification authority to obtain test requirements specific to their modem. Note that this document is not intended to provide information regarding how to achieve the requirements contained herein; modem designers/vendors should refer to applicable requirements documents issued by Delta 8 SATCOM .

1.5 Special Types of Modems. Special cases of general requirements are addressed in the appendices for specific types of modems. The Program Office, without approval from the certification authority, may instruct a manufacturer to replace a Section 5 paragraph with the appropriate appendix paragraph, or to otherwise enforce an appropriate appendix.

1.6 Requests to deviate from the standard. If a modem requires deviation from the specifications stated herein, the Government sponsor Program Manager (PM) should process a request to deviate from the standard through the certification authority, in accordance with DoD

Manual (DoDM) 4120.24, Defense Standardization Program Procedures. The request should include the mission of the system, the rationale for deviating from the standard, and both the technical and cost impact in the event that the program is not allowed to deviate from the standard. Modems accepted by the Government sponsor PM, which deviate from this standard without first obtaining approval for deviation from the certification authority, are acquired at program risk.

DRAFT DATED 01 JULY 2023

2 APPLICABLE DOCUMENTS

2.1 General. The documents listed in this section are specified in Sections 3, 4, and 5 of this standard. This section does not include documents cited in other sections of this standard or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements of documents cited in Sections 3, 4, and 5 of this standard, whether or not they are listed in Section 2.

2.2 Government documents.

2.2.1 Specifications, standards, and handbooks. The following specifications, standards, and handbooks form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract.

INTERNATIONAL STANDARDIZATION AGREEMENTS

NATO STANAG 4486 - Super High Frequency (SHF) Military Satellite

Communications (MILSATCOM) Frequency

Division Multiple Access (FDMA) Non-EPM

Modem for Services Conforming to Class-B of

STANAG 4484

(Copies of this document may be obtained online at http://www.nato.int.)

DEPARTMENT OF DEFENSE SPECIFICATIONS

A3197423 - Specification for OM-73XX Modem Group

(Copies of this document are available from the U.S. Army Communications-Electronic

Research, Development and Engineering Center, Space and Terrestrial Communications

Directorate, SATCOM Systems Division, Independent Test and Certification Branch (RDER-

STC-CT), 6690 Raritan Avenue, Aberdeen Proving Ground, MD 21005.)

2.2.2 Reports and Studies. The following reports and studies are cited as references within this document.

Navy Studies

Technical Report 1578

(AD-A267 884

- W. McDonald, “SHF SATCOM Terminal Ship-

Motion Study.” Naval Command, Control and

Ocean Surveillance Center, RDT&E Division, San Diego, CA, March 1993.

http://www.nato.int/

2.3 Non-Government publications. The following non-Government documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those listed in solicitation or contract.

DYNAMIC LINK EXCHANGE PROTOCOL (DLEP)

RFC 8175 - Dynamic Link Exchange Protocol

RFC 8629 - Dynamic Link Exchange Protocol Multi-Hop Forwarding

Extension

RFC8651 - Dynamic Link Exchange Protocol Control-Plane_Based Pause

Extension

RFC 8703 - Dynamic Link Exchange Protocol Link Identifier Extension

RFC 8757 - Dynamic Link Exchange Protocol Latency Range Extension

(Copies of these documents are available online at www.rfc-editor.org.

EUROPEAN TELECOMMUNICATIONS STANDARDS INSTITUTE (ETSI)

ETSI EN

301 790

- Digital Video Broadcasting (DVB); Interaction channel for satellite distribution systems

ETSI EN

302 307-1

- Digital Video Broadcasting (DVB); Second Generation

Framing Structure, Channel Coding and Modulation

Systems for Broadcasting, Interactive Services, News

Gathering and Other Broadband Satellite Applications;

Part 1: DVB-S2

ETSI EN

302 307–2

- Digital Video Broadcasting (DVB); Second Generation

Framing Structure, Channel Coding and Modulation

Systems for Broadcasting, Interactive Services, News

Gathering and Other Broadband Satellite Applications;

Part2: DVB-S2 Extensions (DVB-S2X)

(Copies of these documents are available online at http://www.etsi.org.)

INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS (IEEE)

http://www.rfc-editor.org/ http://www.etsi.org/

DRAFT DATED 01 JULY 2023

IEEE 802.3ab - IEEE Standard for Information Technology -

Telecommunications and Information Exchange Between

Systems - Local and Metropolitan Area Networks - Specific

Requirements. Supplement to Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method and

Physical Layer Specifications – Physical Layer Parameters and

Specifications for 1000 Mb/s Operation over Four Pair of

Category 5 Balanced Copper Cabling, Type 1000BASE-T

IEEE 802.3ae IEEE Standard for Information technology – Local and metropolitan area networks – Part 3: CSMA/CD Access

Method and Physical Layer Specifications – Media Access

Control (MAC) Parameters, Physical Layer, and Management

Parameters for 10 Gb/s Operation

IEEE 802.3i IEEE Standard for Local and Metropolitan Area Networks -

System Considerations for Multisegment 10 Mb/s Baseband

Networks (Section 13) and Twisted-Pair Medium Attachment

Unit (MAU) and Baseband Medium, Type 10BASE-T (Section

14)

IEEE 802.3u IEEE Standards for Local and Metropolitan Area Networks:

Supplement - Media Access Control (MAC) Parameters, Physical Layer, Medium Attachment Units, and Repeater for

100Mb/s Operation, Type 100BASE-T (Clauses 21-30)

(Copies of these documents are available from www.ieee.org or the IEEE Service Center, 445

Hoes Lane, Piscataway, NJ 08854-4141.)

INTERNATIONAL TELECOMMUNICATIONS SATELLITE ORGANIZATION

(INTELSAT) EARTH STATION STANDARDS (IESSs)

IESS-308 - Performance Characteristics for Intermediate Data Rate

Digital Carriers Using Convolutional Encoding/Viterbi

Encoding and QPSK Modulation (QPSK/IDR)

IESS-309 - Performance Characteristics for INTELSAT Business

Services (IBS)

IESS-310 - Performance Characteristics for Intermediate Data Rate

Digital Carriers Using Rate 2/3 TCM/8PSK and Reed–

Solomon Outer Coding (TCM/IDR)

IESS-315 - Performance Characteristics for VSAT Service Using

Turbo Coding with QPSK/OQPSK Modulation

(Copies of these documents are available from INTELSAT General Communications LLC, 7900 Tysons One Place, Suite 12, McLean, VA 22102, telephone +01 703-270-4200, facsimile

+01 703-270-4810, or online at http://www.intelsat.com.)

INTERNET ENGINEERING TASK FORCE (IETF)

http://www.ieee.org/ http://www.intelsat.com/

DRAFT DATED 01 JULY 2023

RFC-5578 - PPP over Ethernet (PPPoE) Extensions for Credit Flow and Link Metrics

(Copies of this document is available online at http://www.rfc-editor.org.)

PPP OVER ETHERNET (PPPoE)

RFC 5578 - PPP over Ethernet (PPPoE) Extensions for Credit Flow and

Link Metrics

RFC 2516 - A method for Transmitting PPPoE

(Copies of these documents are available online at http://www.rfc-editor.org.)

RADIO-ROUTER CONTROL PROTOCOL (R2CP)

RFC ???? - Radio-Router Control Protocol

TELECOMMUNICATIONS INDUSTRY ASSOCIATION (TIA)

TIA-422 - Electrical Characteristics of Balanced Voltage Digital

Interface Circuits

TIA-423 - Electrical Characteristics of Unbalanced Voltage Digital

Interface Circuits

TIA-530 - High Speed 25-Position Interface for Data Terminal

Equipment and Data Circuit-Terminating Equipment, Including Alternative 26-Position Connector

TIA-612 - Electrical Characteristics for an Interface at Data

Signaling Rates up to 52 Mbit/s

TIA-613 - High Speed Serial Interface for Data Terminal Equipment and Data Circuit-Terminating Equipment

(Copies of these documents are available online at http://www.tiaonline.org.)

2.4 Order of precedence. Unless otherwise noted herein or in the contract, in the event of a conflict between the text of this document and the references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained.

http://www.tiaonline.org/

3 DEFINITIONS

3.1 Definitions of terms. Definitions of terms not listed in this section are as defined in the Alliance for Telecommunications Industry Solutions (ATIS) Telecom Glossary.

3.2 Abbreviations. The abbreviations used in this MIL-STD are defined as follows.

8-PSK Eight-Phase-Shift Keying

ACI Adjacent Channel Interference

ACM Adaptive Coding and Modulation

AGC Automatic Gain Control

AH Antenna Handover

ANSI American National Standards Institute

ATIS Alliance for Telecommunications Industry Solutions

AUPC Automated Uplink Power Control

BCI Bit-Count Integrity

BER Bit Error Ratio

BPSK Binary Phase-Shift Keying

C-SSE Consolidated Wideband SATCOM System Expert

C3I Command, Control, Communications, and Intelligence

CDMA Code-Division Multiple Access

CE Constellation Error

CSMA/CD Carrier-Sense Multiple Access with Collision Detection

CW Continuous Wave

DEM Distant-End Monitoring

DISA Defense Information Systems Agency

DLEP Dynamic Link Exchange Protocol

DoD Department of Defense

DoDIN Department of Defense Information Networks

DoDM Department of Defense Manual

DSCS Defense Satellite Communications System

DSSS Direct Sequence Spread Spectrum

DVB Digital Video Broadcasting

EBEM Enhanced Bandwidth Efficient Modem

Eb/No Energy per Bit to Noise Ratio

ESD Energy Spectral Density

ES/No Energy per Symbol to Noise Ratio

ETSI European Telecommunications Standards Institute

EVM Error Vector Magnitude

FDMA Frequency-Division Multiple Access

FEC Forward Error Correction

FHSS Frequency-Hopping Spread Spectrum

HSSI High Speed Serial Interface

GFP Generic Framing Protocol

DRAFT DATED 01 JULY 2023

GSE Generic Stream Encapsulation

G/T Receive Antenna Gain / Noise Temperature

HSSI High Speed Serial Interface

I In-Phase Component

IBS INTELSAT Business Services

IDR Intermediate Data Rate

IEEE Institute of Electrical and Electronics Engineers

IESS INTELSAT earth station standard

IETF Internet Engineering Task Force

IF Intermediate Frequency

INTELSAT International Telecommunications Satellite Organization

IP Internet Protocol

ISO International Organization for Standardization

ITA Information Throughput Adaptation

ITU-T International Telecommunications Union –

Telecommunication Standardization Sector

LNA Low Noise Amplifier

MAC Media Access Control

MAI Multiple Access Interface

MF-TDMA Multiple Frequency Time Division Multiple Access

MILSATCOM Military Satellite Communications

MIL-STD Military Standard modcod modulation and code rate combination

NATO North Atlantic Treaty Organization

OQPSK Offset Quadrature Phase-Shift Keying

PFSD Power Flux Spectral Density

PM Program Manager

PPP Point-to-Point Protocol

PPPoE Point-to-Point Protocol over Ethernet

PSD Power Spectral Density

PSK Phase-Shift Keying

Q Quadrature-Phase Component

QEF Quasi Error Free

QPSK Quadrature Phase-Shift Keying

R2CP Radio-Router Control Protocol

R2RI Radio-to-Router Interface

RF Radio Frequency

RMS Root Mean Square

RD Data Rate

RS Reed–Solomon

RS Symbol Rate

Rx Reception

SATCOM Satellite Communications

SHF Super High Frequency

SOW Statement Of Work

STANAG Standardization Agreement

DRAFT DATED 01 JULY 2023

TDMA Time-Division Multiple Access

TIA Telecommunications Industry Association

Tx Transmission

USSF United States Space Force

VLAN Virtual Local Area Network

VSAT Very Small Aperture Terminal

VSWR Voltage Standing-Wave Ratio

WGS Wideband Global SATCOM

3.3 Accuracy. The degree of conformity of a measured or calculated value to its definition, related to the offset from an ideal value.

3.4 Acquisition. Condition reflecting carrier and decoder lock.

3.5 Back to back. Refers to Intermediate Frequency (IF) testing of modems in which two identical modems are used with adequate physical separation to prevent any interaction beyond IF connectivity.

3.6 Baud. Elemental unit of transmission; e.g. “symbol” or “chip.”

3.7 Bit Error Ratio (BER). The number of bit errors divided by the total number of transferred bits during a specified time interval.

3.8 Chip. A baud element in a Direct Sequence Spread Spectrum (DSSS) spreading sequence.

3.9 Chip rate (RC). The baud rate of a DSSS spreading sequence.

3.10 Data rate (RD). The rate at which data traffic, incident upon one or more data interfaces, is transferred across a satellite channel, measured in bits per second (bits/s).

3.11 Data synchronization. Condition reflecting demodulated data at the reception

(Rx) data traffic interface subsequent to successful de-framing and decryption where relevant.

3.12 dBc. Ratio of a non-carrier power component to the total power in a carrier, expressed in decibels (dB).

3.13 Eb/N0. The ratio of energy per bit to noise Power Spectral Density (PSD), typically expressed in dB. Converts from ES/N0 using

𝐸b 𝑁0

𝐸S

𝑁0 − 10 log10

𝑅D

𝑅S

3.14 Error Vector Magnitude (EVM). Sometimes referred to as “constellation error”

(CE), EVM is a measurement used to quantify the performance of a digital radio transmitter.

EVM is expressed in percent Root Mean Square (RMS) and is computed as follows.

DRAFT DATED 01 JULY 2023

𝐸𝑉𝑀 =

NS

∑ |𝜖(kS)|2

NS − 1

kS = 0

NC

∑ 𝐼ref

2(kC) + 𝑄ref 2(kC)

NC − 1

kC = 0

Where:

NS = the number of symbols over which the EVM measurement is taken;

kS = the symbol index;

NC = the number of constellation points in the modulation waveform = 2mod index;

kC = the constellation point index;

𝐼ref(kC) = in-phase coordinate of kc indexed ideal constellation point;

𝑄ref(kC) = quadrature-phase coordinate of kc indexed ideal constellation point.

And 𝜖(kS) = √𝐼err 2(kS) + 𝑄err

2(kS)

𝐼err(kS) = 𝐼actual(kS) − 𝐼ref(kS);

𝐼actual(kS) = in-phase coordinate of kS indexed actual constellation point;

𝑄err(kS) = 𝑄actual(kS) − 𝑄ref(kS);

𝑄actual(kS) = quadrature coordinate of kS indexed actual constellation point.

3.15 ES/N0. The ratio of energy per symbol to noise PSD, typically expressed in dB.

Converts from Eb/N0 using

𝐸S

𝐸b 𝑁0 + 10 log10

3.16 Frequency uncertainty. The difference between a received signal’s expected frequency and its actual frequency. Frequency uncertainty results when 1) a difference in frequency between reference oscillators exists, 2) Doppler effects cause frequency shifts, or 3) frequency setting inaccuracies exist.

3.17 Modem emulation. A standardized or otherwise prescribed set of rules governing the signal processing and waveform construction required to produce a conforming modulation waveform. Conformance to specified modem emulations is the basis for waveform-level interoperability between modems.

3.18 Punctured code. A higher-rate code obtained by periodically deleting bits from a lower-rate code.

DRAFT DATED 01 JULY 2023

3.19 Quasi Error Free ES/N0 (QEF ES/N0). The threshold ES/N0 specified for BER =

10-10 (PER=10-7). If the threshold ES/N0 is not specified for BER = 10-10 (PER=10-7), then it shall be extrapolated from the next higher specified threshold BER at a rate of 0.05 dB of ES/N0 per factor of 10 BER.

3.20 Reference ES/N0. A threshold relevant to some specified performance as an underlying condition. Reference ES/N0 often corresponds to a stated BER value.

3.21 Stability. The degree to which an oscillating signal produces the same frequency for a specified time interval.

3.22 Symbol rate (RS). The rate at which symbols are transferred across a satellite channel, measured in symbols per second (sym/s).

3.23 Threshold Eb/N0. The Eb/N0 at which the measured BER must not exceed the specified BER.

Threshold 𝐸b 𝑁0 = Threshold

𝐸S

𝑁0 − 10 log10

3.24 Threshold ES/N0. The ES/N0 at which the measured BER must not exceed the specified BER.

Threshold

𝑁0 = Threshold

𝐸b 𝑁0 + 10 log10

4 GENERAL REQUIREMENTS

4.1 Overview. This section defines the subject modem and specifies the conditions under which it operates. A description of general modem transmission, reception, and control and monitor functions is provided in 4.2. The relevant operating environment is described in 4.3;

4.4 describes unique DoD environmental conditions under which the subject modem must operate.

4.2 Modem description. A modem shall implement one or more transmission functions and one or more reception functions, along with associated control and monitoring functions. Separate transmission and reception functions shall be implemented as applicable for different applications and asymmetric data rates. A modem functional overview is shown on

FIGURE 1.

FIGURE 1. Modem functional overview.

4.2.1 Transmission function. The transmission function shall accept data signals from a digital data source and use these digital data signals to modulate an IF carrier in accordance with one or more prescribed modem standards. The transmission function shall then send this IF signal to an IF output interface. Prescribed modem standards define the following transmission functions and components.

a. Data input interface(s).

b. Provisions for automated power control, where applicable.

c. Provisions for adaptive coding and modulation, where applicable.

d. Provisions for supporting distant-end status monitoring, where applicable.

e. Internal service channel source.

f. Service multiplexer.

g. Encryption.

h. Scrambling for purposes of data randomization.

i. Encoding for mitigation of Antenna Handover Effects, where applicable.

j. Differential encoding.

k. Forward Error Correction (FEC) encoding.

l. Symbol-level carrier modulation.

m. Modulation framing.

n. IF output interface.

4.2.2 Reception function. The reception function shall receive an IF signal from an IF input interface. The reception function shall then demodulate this IF signal in accordance with one or more prescribed modem standards. The reception function shall then send data and, if necessary, timing derived from the data, to a digital data sink. Prescribed modem standards define the following reception functions and components.

a. IF input interface.

b. Modulation de-framing.

c. Symbol-level carrier demodulation.

d. FEC decoding.

e. Differential decoding.

f. Decoding for mitigation of AH effects, where applicable.

g. Descrambling for purposes of data de-randomization.

h. Decryption.

i. Service demultiplexer.

j. Internal service channel sink.

k. Provisions for distant-end status monitoring, where applicable.

l. Provisions for supporting distant-end adaptive coding and modulation, where applicable.

m. Provisions for supporting distant-end automated power control, where applicable.

DRAFT DATED 01 JULY 2023

n. Data output interface(s).

4.2.3 Control and monitoring functions. The modem shall interface with external controlling and monitoring components.

4.3 Operational conditions. Unless otherwise specified, the requirements specified in this MIL-STD shall be met over the range of environmental conditions specified by the relevant procuring authority.

4.4 Environmental perturbation. Active links shall not lose acquisition, nor serial data traffic ports lose bit count integrity, at the ES/N0 required for BER = 10-10 (PER=10-7), over the range of environmental conditions specified by the procuring authority. This shall include, as a minimum,

a. Exposure to temperature deviation.

b. Exposure to vibration.

c. Exposure to shock on the outside surface of the modem, simulating maintenance, operator or other external action on the modem.

5 DETAILED REQUIREMENTS

5.1 Overview. This section provides detailed requirements that address every major modem interface, subsystem, and performance category.

5.2 Frequency reference. Modems shall accept an external frequency reference signal as follows.

a. Signal type: sinusoidal.

b. Frequency: either 5 MHz or 10 MHz, at least one or the other.

c. Input impedance: 50 Ω (nominal).

d. Input signal level: +6 to +16 dBm.

e. Maximum VSWR: 1.5:1.

Modems shall include an internal frequency reference for accuracy and stability when an external frequency reference signal is not present.

5.3 Baseband interfaces. In 5.3.1–5.3.3, modem baseband traffic interfaces are defined in terms of data rates and their granularity, mandatory Internet Protocol (IP)-centric

Ethernet data interfaces, and optional legacy serial interfaces.

DRAFT DATED 01 JULY 2023

5.3.1 Data rates. The data rate resolution for all modems shall be in 1-bit-per-second increments. The minimum and maximum data rates shall be specified by the procuring authority.

5.3.2 Ethernet data interfaces. Ethernet data interfaces shall be implemented in accordance with

a. IEEE 802.3i (10Base-T), IEEE 802.3u (100Base-T) and IEEE 802.3ab (1000Base-T);

b. or IEEE 802.3ae (10 Gigabit Ethernet).

5.3.2.1 Ethernet flow control.When implementing radio aware routing, for the sake of adaptive coding and modulation (ACM) or otherwise, modems that implement Ethernet data interfaces shall support PPPoE with extensions introduced in RFC-5578 for credit-based session flow control and session-based link metric quality reports.

5.3.2.2 Radio-router signaling. Messaging between modem and router is useful for signaling

• Link establishment and termination;

• Link quality metrics;

• Flow control.

As such, it is recommended that the modem implement one or more of the following Radio-to-

Router Interfaces (R2RI) to exchange such signaling with the router.

a.RFC 5578 (PPPoE with credit flow and link metrics extensions);

b.R2CP (Radio-Router Control Protocol using 802.1Q VLANs) c.DLEP (Dynamic Link Exchange Protocol).

For flow control alone, it is recommended that the external LAN interface be compliant with the optional MAC Control protocol of section 31 of the Ethernet/IEEE 802.3 standard for real‐time flow control. As a minimum, the modem shall accept and exercise Ethernet pause frames for flow control.

5.3.3 Serial data interfaces. When equipped with serial data interfaces, the modem shall operate with one or more baseband data interfaces that conform to one or more of the formats described in 5.3.3.1–5.3.3.3, as selected by the procuring authority.

5.3.3.1 High Speed Serial Interface. High Speed Serial Interface (HSSI) shall be in accordance with TIA-612 and TIA-613.

5.3.3.2 Balanced serial. Balanced serial with electrical characteristics shall be in accordance with TIA-422; mechanical characteristics shall be in accordance with TIA-530.

5.3.3.3 Unbalanced serial. Unbalanced serial with electrical characteristics shall be in accordance with TIA-423; mechanical characteristics shall be in accordance with TIA-530.

DRAFT DATED 01 JULY 2023

5.4 Modem emulations.

a. In 5.4.1–5.4.12, modem emulations are defined, where possible, by referencing military or commercial modem standards. The list of modem emulations begins with Continuous

Wave (CW), a trivial case necessary for test and diagnostic purposes. In 5.4.7–5.4.11, four explicit modem emulations are generally defined by referencing external standards. In 5.4.12, provisions for introducing additional modem emulations beyond those indicated here are described.

b. The modem shall implement one or more of the following modem emulations in accordance with the prescribed standards as indicated in 5.4.1–5.4.11, subject to the determination of the procuring authority.

c. Each modem emulation implemented shall include provisions for uncoded operation of every modulation format employed.

5.4.1 Continuous wave. The modem shall be able to output an unmodulated signal.

This emulation is mandatory.

5.4.2 OM-73. OM-73-compliant emulations shall be in accordance with the following paragraphs of A3197423, and as otherwise indicated.

a. Generally in accordance with Transmitter Module Characteristics.

b. Scrambling in accordance with Bit Randomizer.

c. Differential encoding in accordance with Differential Encoder and Interface.

d.FEC encoding in accordance with FEC Encoder, and with the punctured code patterns shown in TABLE I below.

TABLE I. FEC punctured code patterns

Code

Rate Symbol

Transmission Bit Sequence and Puncture Pattern

B1 B2 B3 B4 B5 B6 B7

3/4 P11 1 2

1 1 1 1

P23 1 1 1 1 1

7/8 P1 1 1 1

P2 1 1 1 1 1 1 P1 = 1718 polynomial output.

2 = Deleted bit.

3 P2 = 1338 polynomial output.

DRAFT DATED 01 JULY 2023

e. Symbol-level carrier modulation in accordance with RF Modulator.

(1) For Binary Phase-Shift Keying (BPSK), transmitting P2 followed by P1, according to the puncture pattern shown in TABLE I.

(2) For Quadrature Phase-Shift Keying (QPSK) and Offset Quadrature Phase-

Shift Keying (OQPSK), with symbol mapping as presented in TABLE II below.

TABLE II. QPSK and OQPSK symbol mapping.

Rate Channel

Number of Transmitted Symbols

S1 S2 S3 S4 S5 S6 S7

1/2 I1 P12 (B1) P1 (B2) P1 (B3) P1 (B4) P1 (B5) P1 (B6) P1 (B7)

Q3 P24 (B1) P2 (B2) P2 (B3) P2 (B4) P2 (B5) P2 (B6) P2 (B7)

3/4 I P1 (B1) P1 (B3) P1 (B4) P1 (B6) P1 (B7) -- --

Q P2 (B1) P2 (B2) P2 (B4) P2 (B5) P2 (B7) -- --

7/8 I P1 (B1) P2 (B3) P1 (B5) P1 (B7) -- -- --

Q P2 (B1) P2 (B2) P2 (B4) P2 (B6) -- -- -- 1 I = In-phase component.

2 P1 = 1718 polynomial output.

3 Q = Quadrature-phase component.

4 P2 = 1338 polynomial output.

5.4.3 Legacy MIL-STD-188-165. Legacy MIL-STD-188-165-compliant emulations shall be implemented as follows.

a. Scrambling selectable from:

(1) No scrambling.

(2) OM-73-compliant scrambling in accordance with A3197423, Bit

Randomizer.

(3) Scrambling in accordance with the energy dispersal (scrambling) requirements of IESS-308, IESS-309, and IESS-310.

b. Differential encoding shall be either disabled or:

(1) For BPSK, bit-wise.

(2) For QPSK and OQPSK, separate for I and Q.

(3) For 8-PSK, in accordance with IESS-310.

c. FEC encoding.

(1) Reed-Solomon (RS) outer codes shall be selectable from the following options.

DRAFT DATED 01 JULY 2023

(a) No outer code.

(b) RS(126,112) for data rates below 512 kilobits-per-second (kb/s).

(c) RS(219,201) for data rates greater than or equal to 512 kb/s.

(d) RS(225,205) at any rate.

(2) Interleaver depth shall be selectable, either 4 or 8, for use when RS outer codes are selected.

(3) For BPSK, QPSK, and OQPSK, selectable convolutional encoding with 7-bit constraint-length convolutional encoding polynomials P1 = 1718 and P2 = 1338 and punctured code patterns shall be as presented in III.

TABLE III. BPSK, QPSK, and OQPSK punctured code patterns.

Rate Symbol

Transmission Bit Sequence and Puncture Pattern

B1 B2 B3 B4 B5 B6 B7

3/4 P11 1 2

1 1 1 1

P23 1 1 1 1 1

7/8 P1 1 1 1

P2 1 1 1 1 1 1 P1 = 1718 polynomial output.

2 = Deleted bit.

3 P2 = 1338 polynomial output.

(4) For 8-PSK, rate 2/3 pragmatic trellis FEC coding and signal mapping shall be in accordance with IESS-310.

d. Symbol-level carrier modulation.

(1) For BPSK, QPSK, and OQPSK, in accordance with 5.4.2.e of this document.

(2) For 8-PSK, in accordance with IESS-310.

5.4.4 IESS-308. Modems that implement IESS-308 emulations shall do so in accordance with IESS-308.

5.4.5 IESS-309. Modems that implement IESS-309 emulations shall do so in accordance with IESS-309.

5.4.6 IESS-310. Modems that implement IESS-310 emulations shall do so in accordance with IESS-310.

5.4.7 IESS-315. Modems that implement IESS-315 emulations shall do so in accordance with IESS-315.

DRAFT DATED 01 JULY 2023

5.4.8 ETSI EN 301 790 (DVB RCS). Modems that implement ETSI EN 301 790 emulations shall do so in accordance with ETSI EN 301 790.

5.4.9 NATO STANAG 4486. Modems that implement NATO STANAG 4486 emulations shall do so as follows.

a. In general, in accordance with NATO STANAG 4486 annexes relevant to “EBEM.”

b. IP encapsulation shall be in accordance with NATO STANAG 4486 section entitled

“Packet Channel” and its subsections.”

c. When applicable, provisions for Automated Uplink Power Control shall be in accordance with NATO STANAG 4486 section entitled “AUPC.”

d. When applicable, provisions for Information Throughput Adaptation (ITA) (adaptive coding and modulation) shall be in accordance with NATO STANAG 4486 section entitled

“ITA.”

e. When applicable, provisions for Distant-End Monitoring shall be in accordance with

NATO STANAG 4486 section entitled “DEM.”

f. When applicable, embedded channel interfaces shall be in accordance with NATO

STANAG 4486 sections entitled “Embedded Channel,” “Embedded Channel Interfaces” and

“Embedded Channel GFP Acquisition and Synchronization Procedures.”

g. Service multiplexers shall be in accordance with NATO STANAG 4486 sections entitled Frame Format #1 (ITA),” “Multiplexor” and “Frame Format #2 (AH).”

h. Encryption shall be in accordance with NATO STANAG 4486 sections entitled

“Encryption.”

i. Selectable scrambling shall be in accordance with NATO STANAG 4486 sections entitled “Scrambler.”

j. When applicable, encoding for mitigation of AH effects shall be in accordance with

NATO STANAG 4486 sections entitled “Frame Format #2 (AH),” “Antenna Handover,”

“Antenna Handover Interface” and “Antenna Handover Cable.”

k. FEC encoding shall be in accordance with NATO STANAG 4486 section entitled

“Turbo Code and 16-ary Modulation Air Interface,” specifically the subsection entitled

“Turbo Code.”

l. Symbol-level carrier modulation shall be in accordance with NATO STANAG 4486 sections entitled “Symbol Generation” and “Symbol Mapping.”

DRAFT DATED 01 JULY 2023

m. Modulation framing shall be in accordance with NATO STANAG 4486 section entitled “Frame Structure,” “Frame Structures” and “Frame Format #2 (AH)” as applicable.

5.4.10 ETSI EN 301 790 (DVB-S2). Modems that implement ETSI EN 301 790 emulations shall do so in accordance with ETSI EN 301 790.

5.4.11 ETSI EN 302 307–2 (DVB-S2X). Modems that implement ETSI EN 302 307–2 emulations shall do so in accordance with ETSI EN 302 307–2.

5.4.12 New modem emulations. New modem emulations may be considered for inclusion in this standard under the following conditions.

a. The waveform is specified

1. in accordance with open commercial standards available to Government and vendor communities,

2. or in accordance with other Government standards.

b. The waveform satisfies a need not met by existing waveforms cited in this standard.

c. The waveform is free of intellectual property restrictions.

5.5 IF output interface. In 5.5.1–5.5.6, modem IF (transmission) output is specified.

5.5.1 IF output frequency bands. The modem shall support a 950 to 2000 MHz IF interface. Additional IF interfaces and minimum bandwidths may be chosen by the procuring authority from the following list.

a. 70 ± 18 MHz

b. 140 ± 36 MHz

c. 700 ± 62.5 MHz

Modem performance parameters detailed in this standard shall be met for all waveforms whose -25 dBc bandwidths are contained within the bandwidth limits of the corresponding IF interface.

5.5.2 Output impedance. The IF interfaces shall have a nominal impedance of 50 Ω.

The Voltage Standing-Wave Ratio (VSWR) over the IF band shall be less than 1.5:1 for IF band center frequencies below 1 GHz and 2.0:1 for IF band center frequencies above 1 GHz.

5.5.3 IF output carrier.

5.5.3.1 IF output carrier frequency. The modem shall provide an IF output carrier configurable in 1-kHz steps, or sub-multiples thereof.

DRAFT DATED 01 JULY 2023

5.5.3.2 IF stability. The IF output carrier frequency shall be stable to within 10−8 per day without frequency source adjustments.

5.5.3.3 IF accuracy. When an external frequency reference is not present, the IF output carrier frequency shall be within 10−7 of the selected value after a 1-hour warm-up period. When an external frequency reference is present, the IF output carrier frequency shall be within 10−7 of the selected value without a warm-up period.

5.5.3.4 Phase noise. The single-sided phase noise PSD 𝑆∅(𝑓) shall not exceed the phase noise PSD threshold 𝑆∅max(𝑓) over the interval [𝑓1, 𝑓2] where

𝑆∅max(𝑓) = 𝐾∅max 𝑓

𝐾∅max = 𝑃∅max − 11.4 dB

𝑃∅max = −20 dB −

𝑁0 QEF max but not to exceed -40.6 dBc

QEF max is the maximum QEF

𝐸S

presented by the modem 𝑓1 = 0.0005 𝑅Smin 𝑓2 = 0.5 𝑅Smax

𝑅Smin is the minimum symbol rate supported by the modem

𝑅Smax is the maximum symbol rate supported by the modem

If 𝑆∅(𝑓) > 𝑆∅max(𝑓) for any 𝑓1 ≤ 𝑓 ≤ 𝑓2, then it shall be required that

2∫ 𝑆∅(𝑓) 𝑑𝑓 ≤ 𝑃∅max

0.5 𝑅S

0.0005 𝑅S

for all symbol rates 𝑅S supported by the modem.

Examples prepared in TABLE IV are illustrated on FIGURE 2.

TABLE IV. Transmitted IF phase noise threshold examples.

Example 𝑅YMSmin 𝑅Smax

𝐸S

𝑁0 QEF max 𝑓1 𝑓2

−20 dB

𝐸S

𝑁0 QEF max

𝑃∅max 𝐾∅max

1 32 64 16 16 32 -36 -40.6 -52

DRAFT DATED 01 JULY 2023

Example 𝑅YMSmin 𝑅Smax

𝐸S

𝑁0 QEF max 𝑓1 𝑓2

−20 dB

𝐸S

𝑁0 QEF max

𝑃∅max 𝐾∅max

2 200 400 28 100 200 -48 -48 -59.4 units ksym/s Msym/s dB Hz MHz dBc dBc dBc

FIGURE 2. Transmitted IF phase noise mask examples.

DRAFT DATED 01 JULY 2023

5.5.4 Output power control range, step size, and accuracy. The absolute accuracy of the carrier power shall be within 1.0 dB of the selected value. The relative accuracy associated with the smallest step increment shall be within 0.1 dB. The minimum step size shall not exceed 0.25 dB. The output power shall be adjustable over the range from 0 to −40 dBm.

When a power change is initiated, the power shall transition monotonically and shall not induce burst errors into the controlled carrier’s bit stream or into the adjacent carrier’s bit stream (with the adjacent carrier spaced at 1.2RS). When the transmission carrier output is set to OFF, signal present at the output, from 0 to 4,000 MHz, shall be no greater than −70 dBm across any 3 MHz bandwidth and not greater than −80 dBm across any 30 kHz bandwidth. These transmission carrier output OFF thresholds are illustrated on FIGURE 3.

FIGURE 3. Transmission carrier output OFF thresholds.

5.5.5 Spectral output.

5.5.5.1 Spectral confinement. The IF output signal shall meet the modulator output signal spectral density mask shown on FIGURE 4. This requirement shall be met when terminating into a 50-Ω load with a VSWR as specified in 5.5.2. It shall be acceptable for transmission spectra to exhibit the following:

a. Carrier nulls at the carrier for BPSK modulation only;

b. Clock nulls, offset by half the symbol rate from the carrier, for BPSK and OQPSK modulation only;

DRAFT DATED 01 JULY 2023

c. PSD not to exceed the Transmit (Tx) thermal noise floor threshold specified in 5.5.5.2 when this threshold exceeds the PSD confinement mask shown on FIGURE 4;

d. Spurious emissions compliant with 5.5.5.3;

e. Output harmonics compliant with 5.5.5.4.

FIGURE 4. Modulator output signal spectral density limit mask.

5.5.5.2 Transmission thermal noise. The IF output thermal noise density shall not exceed the greater of −135 dBm/Hz or −135 dBc/Hz over the full IF band.

5.5.5.3 Transmission output spurious emissions. Spurious emission power in any 10-kHz bandwidth, exceeding -70 dBm, shall be controlled relative to total modulated carrier power as follows.

𝑃spurious ≤ −51 dBc −

𝑁0

QEF

𝑁0

QEF

is the threshold

𝐸S

𝑁0 corresponding to a BER of 10-10 (PER=10-7) for the most spectrally efficient modulation and coding (modcod) supported by the modem;

If the threshold

𝐸S

𝑁0 (or

𝐸b

𝑁0 ) is not specified for a BER of 10-10 (PER=10-7), then the threshold

𝐸S

𝑁0 for the next higher specified BER may be used;

The expression bounding 𝑃spurious is limited above by -51 dBc and below by -70 dBm.

This requirement excludes ±1.0RS centered on the carrier.

5.5.5.4 Transmission output harmonics. The power of any transmission carrier harmonic exceeding -70 dBm shall be controlled, relative to total modulated carrier power, as follows.

a. Within the tunable band, 𝑃harmonic ≤ −51 dBc −

𝑁0

𝑁0

QEF

is as defined in 5.5.5.3;

The expression bounding 𝑃harmonic is limited above by -51 dBc and below by -70 dBm.

b. Outside of the tunable band, the level of any transmission carrier harmonic shall not exceed −70 dBc.

5.5.6 Modulation performance.

DRAFT DATED 01 JULY 2023

5.5.6.1 Spectral inversion. Frequency conversion, if employed, shall not invert the modulator’s output spectrum.

5.5.6.2 Error vector magnitude. Modulation EVM shall not exceed the following thresholds.

a. 6% for BPSK, QPSK and OQPSK;

b. 4% for 8-ary modulation;

c. 3% for 16-ary modulation;

d. 2% for 32-ary modulation or higher.

5.6 IF input interface. In 5.6.1–5.6.4, the modem IF (receive) input is specified in terms of the following.

• Frequency bands (5.6.1) in terms of required L-band, as well as other optional bands.

• Electrical impedance (5.6.2).

• Input carrier (5.6.3) in terms of frequency resolution and uncertainty.

• Input power level (5.6.4) in terms of maximum and minimum desired carrier levels, allowable composite power, and maximum non-damaging input power.

5.6.1 IF input frequency bands. The modem shall support a 950 to 2050 MHz IF interface. Additional IF interfaces and minimum bandwidths may be chosen by the procuring authority from the following list.

a. 70 ± 18 MHz.

b. 140 ± 36 MHz.

c. 700 ± 62.5 MHz.

Modem performance parameters detailed in this standard shall be met for all waveforms whose -25-dBc bandwidths are contained within the bandwidth limits of the corresponding IF interface.

5.6.2 Input impedance. The input shall have a nominal impedance of 50 Ω. The

VSWR over the IF band shall be less than 1.5:1 for IF band center frequencies below 1 GHz and

2.0:1 for IF band center frequencies above 1 GHz.

5.6.3 IF input carrier.

DRAFT DATED 01 JULY 2023

5.6.3.1 IF input carrier frequency. The modem shall accept an IF input carrier configurable in 1-kHz steps, or submultiples thereof.

5.6.3.2 Input frequency uncertainty. The modem shall be able to acquire and demodulate carriers that are within 30 kHz of the nominal expected frequency (5.6.3.1). This includes the maximum offset due to doppler shift (5.7.2.6).

5.6.4 IF input power. The BER shall not be degraded from the requirements specified in 5.7.3 when the composite or desired IF input power levels are as described in 5.6.4.1–5.6.4.2.

5.6.4.1 Desired carrier. The demodulator shall operate with any IF input power level between the minimum and maximum levels specified in 5.6.4.1.1 and 5.6.4.1.2, respectively, for a given IF input carrier and required error performance.

5.6.4.1.1 Minimum operating IF carrier input level. The demodulator shall operate with a minimum carrier level such that:

Pmin = -130 dBm/Hz + ES/N0 + 10 log RS [dBm]

ES/N0 (in dB) is the specified performance value for a BER of 10−8

RS is symbol rate in symbols per second (sym/s).

Where ES/N0 performance is not specified, then:

ES/N0 = Eb/N0 + 10 log RD/RS

Where:

Eb/N0 (in dB) is the specified performance value for a BER of 10−8

RD is data rate in Mbps.

5.6.4.1.2 Maximum operating IF carrier input level. The demodulator shall operate with a maximum carrier level such that

Pmax = -80 dBm/Hz + 10 log RS [dBm]

RS is the symbol rate in sym/s;

Pmax is capped at +0 dBm.

5.6.4.2 IF input overload. The modem shall not be damaged by a continuous IF input up to +25 dBm.

5.6.5 Noise Figure. The demodulator noise figure shall not exceed 27 dB, referenced to the IF input interface and to a physical temperature of 290K. This corresponds to an internal demodulator noise floor not to exceed -147 dBm/Hz.

5.7 Demodulation. In 5.7.1–5.7.3, demodulation performance is specified in terms of the following.

a. Applicability to all modem emulations (5.7.1).

b. Comprehensive acquisition and timing performance (5.7.2).

c. Comprehensive error performance (5.7.3), including baseline BER performance, as well as performance impaired by adjacent channels, high levels of composite power, or self-interference from other modem components.

5.7.1 Demodulation requirements. All IF input carriers, incident on the IF input interface under conditions compliant with 5.6 through 5.6.4.1.2, that have been modulated in accordance with the specifications set forth in 5.4, shall meet performance indicated in 5.7.2 through 5.7.3.4 below.

5.7.2 Acquisition and timing performance requirements. In 5.7.2.1–5.7.2.6, the reference ES/N0 is defined as the specified threshold ES/N0 that corresponds to a BER of 10-4

(PER=10-1). If the threshold ES/N0 is not specified for a BER of 10-4 (PER=10-1), then the reference ES/N0 is extrapolated from the threshold ES/N0 for the highest specified BER point at a rate of 0.05 dB of ES/N0 per BER factor of 10.

5.7.2.1 Initial acquisition. The modem shall achieve initial acquisition within the times shown in TABLE V, with a confidence level of 95 percent over a frequency uncertainty of…