Attachment J-34 - MSBRS OCD Plan Amendment 0003.docx

WILLIAM J. HUGHES TECHNICAL CENTER

Operational Capability Demonstration (OCD) Plan for the Mode S Beacon Replacement System (MSBRS)

Federal Aviation Administration William J. Hughes Technical Center Surface Surveillance Team, ANG-E54 Atlantic City International Airport New Jersey 08405

Document Version Control

Table of Contents

List of Figures

List of Tables

OCD Plan for the MSBRS

SST-C3-PLN-003 V1.21 i June September 2827, 2018

THIS DOCUMENT BECOMES UNCONTROLLED ONCE PRINTED

Introduction Purpose The Mode S Service Life Extension Program (SLEP) Phase 3 has been established by the Federal Aviation Administration (FAA) to address supportability and sustainability issues with the existing Mode S Beacon System Sensor. Under this program, the Mode S Beacon Replacement System (MSBRS) is being acquired as an alternative SLEP approach to replace, rather than refurbish, the legacy Mode S systems. The MSBRS will be a Mode S capable Monopulse Secondary Surveillance Radar (MSSR). This acquisition is focusing on procurement of a Non-Developmental Item (NDI) in an effort to minimize cost and schedule.

As part of the MSBRS source selection process, the Government will conduct an Operational Capability Demonstration (OCD) at the FAA William J. Hughes Technical Center’s (WJHTC) Elwood Experimental En Route Facility, located in Elwood, NJ. Offerors meeting the “Eligibility For Consideration” criteria defined in Section L.7 of the Screening Information Request (SIR) will be invited to participate in an OCD. A separate OCD will be conducted for each qualifying Offeror, and participation is mandatory. Offerors refusing to participate in an OCD will be removed from further consideration. OCD Participants will be required to provide, install, and optimize a fully configured, production representative system meeting the requirements contained in the System/Subsystem Specification (SSS) submitted as part of their proposal and to fully support conduct of the OCD, as defined within this document, at no cost to the Government. The purpose of the OCD is to evaluate the maturity and capabilities of each system. The OCD is structured such that each qualifying NDI system under evaluation will be subjected to a series of target scenario injections, live world data collections, and system functionality demonstrations. Results of the OCD will be used to evaluate system maturity, technical performance, and operational suitability. Data acquired during the evaluation will be used to generate an overall “System Maturity” sub factor score, which will make up part of the Technical Approach factor score in the Offeror proposal evaluation.

Upon conclusion of the initial screening process, the Government will contact the Offerors of qualifying proposals to schedule an OCD. All OCDs will be conducted during the proposal evaluation period, the length of which will be determined by the number of qualifying proposals. The Government does not expect to schedule any OCDs earlier than 45 days after the deadline for receipt of proposals.

Scope This document provides a detailed description of the activities to be performed in support of each OCD, as well as the responsibilities of Offerors. It includes definitions of the target and False Replies Unsynchronized In Time (FRUIT) scenarios that will be generated by the Government for use in the OCD. System configuration requirements during playback of each scenario and the “live world” data collections are identified along with the data recordings to be captured.

Reference Documents The following documents are referenced within this document.

Federal Aviation Administration (FAA) Documents

Non-Government Publications

OCD Overview A maximum of three weeks will be allocated for preparation and conduct of each OCD. During this period, Offerors must install their system, perform any necessary optimization, support conduct of the OCD, and remove their system from the FAA facility. Access to the test site for Offeror personnel will be limited to the hours of 0800 to 1700, local time, Monday through Friday of each week. Offerors will be given two weeks to perform installation and optimization activities. Offerors will be allowed to operate their system in both the live world and scenario playback configurations described within this document in order to accomplish system optimization. If these activities conclude early, the start of OCD conduct will be moved up to the first full day following their completion. OCD conduct is expected to take no more than 5 days. Once OCD conduct begins, each data collection and demonstration event will be performed once and no re-runs will be allowed unless a fault or error occurs on the Government Furnished Equipment (GFE) that adversely affects results.

Proposed systems will be installed in a stand-alone configuration, no primary radar or automation system interfaces will be available. The Government will provide all target and FRUIT scenarios as well as an FAA developed Aircraft Capacity Environment Simulator (ACES) test tool, which is capable of receiving interrogations and injecting simulated target replies at the Radio Frequency (RF) antenna ports of each proposed MSBRS (see section 4 for more information on the ACES tool). Live world data collections will be executed utilizing the front face of a Radiation Systems, Inc. (RSI) Mode S en route antenna, complying with FAA-E-2751. The nominal scan rate for this antenna is 9.6 seconds/scan.

The OCD will be comprised of four major activities, including:

An Offeror presentation Scenario playback/data collection Live world data collection System capabilities demonstration.

The OCD will begin with an Offeror presentation to the Government team that provides a detailed description of the system configuration and adaptation to be utilized, as well as a proposed schedule for OCD conduct. The remaining activities may occur in any order following the presentation. The scenario playback/data collection portion will consist of the collection of system recordings during playback of three separate scenarios. During the live world data collection portion, the system will be connected to a rotating antenna in a beacon only mode of operation while system recordings of Target Of Opportunity (TOO) data are collected. During the system capabilities demonstration, Offeror’s must utilize their proposed system’s Maintenance and Air Traffic terminals to perform typical operations and maintenance activities. The Government expects to complete all of these activities in 4 days or less, with a fifth day allowed as a back-up in the event that unexpected issues occur with GFE or if necessitated by restrictions to live radiation times. If use of a fifth day for OCD conduct results in expiration of the allocated three weeks, one additional day will be granted for equipment removal.

The Government will conduct an independent analysis of the collected data outside of the time designated for OCD activities. Upon completion of the data analysis, the Government OCD team will generate an overall “System Maturity” sub factor score that will be utilized in the technical evaluation.

Offeror Presentation The Offeror presentation delivered at the start of the OCD must last no longer than four hours and must cover, as a minimum, the following topics:

· OCD test bed configuration, including diagrams

· Identification of all system software, including revision number, to be utilized for the OCD

· Identification of all system Line Replaceable Units (LRUs), including revision number, in the system to be utilized for the OCD

· Overview of system adaptation to be utilized during OCD conduct, including:

· If multiple adaptation sets will be used, a description of the differences between each set along with justification for these differences

· A description of any differences between each adaptation set being utilized and the “default” adaptation set along with justification for these differences

· Identification of the mode interlace patterns, interval durations (listening windows), and rollcall scheduling schemes used in each adaptation set

· Identification of the Pulse Repetition Frequency (PRF) and stagger/jitter schemes employed in each adaptation set

· Identification of transmitter output power, by interrogation type, in each adaptation set

· Identification of receiver sensitivity and Sensitivity Time Control (STC) settings in each adaptation set

· Sidelobe suppression technique(s) employed with each adaptation set

· Interrogator Identifier (II) or Surveillance Identifier (SI) code utilized in each adaptation set

· Overview of system recording formats for all data collections required during the OCD

· Discussion of any tools required to parse the system recordings

· Overview of procedures required to calibrate system to the FAA provided simulator, antenna, and azimuth encoder

· Identification of any known issues that may impact results of the OCD

· Proposed schedule for OCD activities The Offeror must provide an electronic copy of all presentation materials to the Government OCD team in Microsoft PowerPoint .ppt or .pptx format compatible with Microsoft Office Suite 2016 at the start of the Offeror presentation. The Offeror presentation must not include any technical material or detail related to system performance or capabilities that is not included in the Offeror’s submitted proposal. The presentation must not include any cost or pricing information. The Government may, at its own discretion, direct the Offeror to skip any portion of the presentation that is deemed irrelevant to conduct of the OCD. Content of the presentation will not influence the “System Maturity” score derived from results of the OCD. Duration of the presentation must be limited to no more than four hours.

Scenario Playback/Data Collection The scenario playback/data collection portion of the OCD will consist of injection of three target scenarios in the presence of simulated FRUIT. The Government will provide all target and FRUIT scenarios required for conduct of the OCD. The three target scenarios include:

1. A capacity target load in a terminal configuration

1. A capacity target load in an En route configuration

1. A maneuvering target scenario presenting stressful situations to the surveillance tracker with the system in a terminal configuration.

Figure 31 provides a high level diagram of the test bed configuration that will be utilized during the scenario playback/data collection portion of the OCD. FAA provided Directional couplers will be attached to the proposed MSBRS Sigma, Delta, and Omega antenna ports; see Section 5 for the physical and electrical characteristics of these couplers. The through port of the couplers will be connected to the equipment building RF transfer switch, via phase matched, semi-rigid cables. The ACES Sigma, Delta, and Omega RF input/output ports will be connected to the forward coupled port of the respective coupler. The equipment building RF transfer switch will be in a position that connects the proposed MSBRS antenna ports to dummy loads during the scenario playback/data collection portion of the OCD. An FAA provided data recording Personal Computer (PC), equipped with a Global Positioning System (GPS) timing card, will be utilized to record and timestamp surveillance data via an Ethernet connection to the surveillance user output port of the proposed MSBRS. Azimuth Change Pulse (ACP) and Azimuth Reference Pulse (ARP) signals generated by the ACES tool will be used to drive the system under test; see section 4 for a description of the physical and electrical characteristics of this interface. An FAA developed Surveillance Trace and Timestamping System 1 (STATS1) tool will be utilized to timestamp and record ACP and ARP data to support system latency analysis; the STATS1 tool accepts single ended Transistor-To-Transistor Logic (TTL), up to +12V, or differential ACP/ARP data.

During playback of each target scenario, the ACES will simultaneously inject ATCBRS and Mode S FRUIT as defined in Section 3.2.4. The scenarios to be utilized during conduct of the OCD, along with the system configuration and system data recordings required during their playback, are described in the sections that follow.

Figure 31: Scenario Playback/Data Collection Configuration Diagram Terminal Capacity Scenario Scenario Description The terminal capacity scenario consists of 700 static beacon targets distributed across a full 360-degree scan and arranged in accordance with the requirements in section 3.2.11.1 of FAA-E-7716 and 3.11.2.1.1.6 of the MSBRS Statement of Work (SOW) as follows, beginning at 0 degrees:

· 250 beacon targets within a 90-degree quadrant (0 – 90 degrees)

· 1.2-degrees with no targets (90 – 91.2 degrees)

· 100 beacon targets within two contiguous 11.25-degree sectors (91.2 – 113.7 degrees)

· 1.2-degrees with no targets (113.7 – 114.9 degrees)

· 32 beacon targets within a 2.4-degree wedge (114.9 – 117.3 degrees)

· 1.2-degrees with no targets (117.3 – 118.5 degrees)

· 318 beacon targets within 240.3-degrees (118.5 – 358.8 degrees)

· 1.2-degrees with no targets (358.8 – 0 degrees) Targets are uniformly distributed in slant range from 1.0 to 60 Nautical Miles (NMI) and in azimuth within each azimuthal grouping defined above. All targets have a reply probability of 100%. Figure 32 illustrates the locations of targets in this scenario. The embedded Terminal Capacity Targets.xlsx file below identifies the start time, end time, range, and azimuth of these targets; a separate worksheet is provided within this file for the targets in each azimuthal group:

The target mix within each of the defined azimuthal groups is as follows:

· 80% Mode S RTCA/DO-181E compliant targets with the following characteristics:

· 80% of targets with discreet Mode 3/A codes

· 20% of targets with non-discreet Mode 3/A codes

· 20% Air Traffic Control Radar Beacon System (ATCRBS) RTCA/DO-181E compliant targets with the following characteristics:

· 80% of targets with discreet Mode 3/A codes

· 20% of targets with non-discreet Mode 3/A codes None of the Mode S targets in this scenario are capable of replying to Ground Initiated Comm-B (GICB) requests. Targets are introduced at random locations distributed throughout each of the four azimuthal groups defined above at a rate of 50 targets every 3rd scan until the capacity is reached. The scenario continues for 30 minutes after all of the targets have been introduced.

Figure 32: Terminal Capacity Scenario Targets Required System Configuration The system must be configured in accordance with the parameters listed in Table 31 during playback of the terminal capacity scenario.

Table 31: Terminal Capacity Required System Configuration Parameters

Notes:

1. ATCRBS PRF is calculated as the sum of all Mode 3/A, Mode C, Mode 2, Mode 3/A-Only All-Call, and Mode C-Only All-Call interrogations within a single Pulse Repetition Interval (PRI) divided by the PRI, in seconds, with no stagger applied.

2. Mode S All-Call PRF is calculated as the sum of all Mode S All-Call interrogations within a single PRI divided by the PRI, in seconds, with no stagger applied.

Data Recordings The Offeror must provide all tools necessary to generate and parse the system data recordings generated during injection of the terminal capacity scenario. The Offeror must provide electronic copies of all raw and parsed data recordings to the FAA no later than at the conclusion of OCD conduct. These files must be identical in format to the System Maturity Support Information described in section L.19.2.5.5 of the MSBRS SIR and submitted with their proposal. At a minimum, the following data types must be recorded on the system during injection of the terminal capacity scenario:

· Disseminated plot data (internal system recording)

· Interrogations (both scheduled and generated)

· Replies received.

Performance Parameters Being Evaluated Data recordings collected during playback of the terminal capacity scenario will be used to evaluate the following performance parameters:

· Target/FRUIT capacity

· Interrogation rates

· Probability of detection (Pd)

· Code accuracy and validity

· False targets

· Positional accuracy

· Latency

· Target acquisition/dissemination time

· Mode S/ATCRBS merging En Route Capacity Scenario Scenario Description The en route capacity scenario consists of 1400 beacon targets distributed across a full 360-degree scan and arranged in accordance with the requirements in section 3.2.11.2 of FAA-E-7716 and 3.11.2.1.1.6 of the MSBRS SOW as follows, beginning at 0 degrees:

· 350 beacon targets within a 90-degree quadrant (0 – 90 degrees)

· 1.2-degrees with no targets (90 – 91.2 degrees)

· 100 beacon targets within two contiguous 11.25-degree sectors (91.2 – 113.7 degrees)

· 1.2-degrees with no targets (113.7 – 114.9 degrees)

· 32 beacon targets within a 2.4-degree wedge (114.9 – 117.3 degrees)

· 1.2-degrees with no targets (117.3 – 118.5 degrees)

· 918 beacon targets within 240.3-degrees (118.5 – 358.8 degrees)

· 1.2-degrees with no targets (358.8 – 0 degrees) Targets are uniformly distributed in slant range from 1.0 to 256 NMI and in azimuth within each azimuthal grouping defined above. All targets have a reply probability of 100%. Figure 33 illustrates the location of targets in this scenario. The embedded En Route Capacity Targets.xlsx file below identifies the start time, end time, range, and azimuth of these targets; a separate worksheet is provided within this file for the targets in each azimuthal group:

The target mix within each of the defined azimuthal groups is as follows:

· 80% Mode S RTCA/DO-181E compliant targets with the following characteristics:

· 80% of targets with discreet Mode 3/A codes

· 20% of targets with non-discreet Mode 3/A codes

· 20% ATCRBS RTCA/DO-181E compliant targets with the following characteristics:

· 80% of targets with discreet Mode 3/A codes

· 20% of targets with non-discreet Mode 3/A codes None of the Mode S targets in this scenario are capable of replying to GICB requests. Targets are introduced at random locations distributed throughout each of the four azimuthal groups defined above at a rate of 50 targets every 3rd scan until the capacity is reached.

Figure 33: En Route Capacity Scenario Targets Required System Configuration The system must be configured in accordance with the parameters listed in Table 32 during playback of the en route capacity scenario.

Table 32: En Route Capacity Required System Configuration Parameters

1. ATCRBS PRF is calculated as the sum of all Mode 3/A, Mode C, Mode 2, Mode 3/A-Only All-Call, and Mode C-Only All-Call interrogations within a single PRI divided by the PRI, in seconds, with no stagger applied.

2. Mode S All-Call PRF is calculated as the sum of all Mode S All-Call interrogations within a single PRI divided by the PRI, in seconds, with no stagger applied.

Data Recordings The Offeror must provide all tools necessary to generate and parse the system data recordings generated during injection of the en route capacity scenario. The Offeror must provide electronic copies of all raw and parsed data recordings to the FAA no later than at the conclusion of OCD conduct. These files must be identical in format to the System Maturity Support Information described in section L.19.2.5.5 of the MSBRS SIR and submitted with their proposal. At a minimum, the following data types must be recorded on the system during injection of the en route capacity scenario:

· Disseminated plot data (internal system recording)

· Interrogations (both scheduled and generated)

· Replies received.

Performance Parameters Being Evaluated Data recordings collected during playback of the en route capacity scenario will be used to evaluate the following performance parameters:

· Target/FRUIT capacity

· Interrogation rates

· Pd

· Code accuracy and validity

· False targets

· Positional accuracy

· Latency

· Target acquisition/dissemination time Surveillance Tracker Stress (STS) Scenario Scenario Description The Surveillance Tracker Stress (STS) scenario includes 13 target groups consisting of 1 to 4 targets, each performing distinct maneuvers designed to stress basic functions of the system’s surveillance tracker. The proposed MSBRS will be in a terminal configuration for playback of this scenario. All targets in this scenario have a 100% reply probability. The sections below provide a description of each target group, the maneuvers performed by each target within the group, and the tracker functions they are designed to exercise.

STS Scenario Target Group 1: Zenith Cone and Intersecting Tracks Target group 1 is comprised of four Mode S aircraft with discrete Mode 3/A Codes that engage in multiple conflicts and a zenith cone crossing as described below and illustrated in Figure 34 (labels in the figure indicate the start point for each target).

· Conflict 1: This conflict involves three aircraft, one flying south along the zero degree radial when its path is intersected at a common point in time by two other aircraft. A vertical separation of 600 feet exists between the paths of the three aircraft. The objective of this conflict is to test the sensor’s ability to track a target in the area of azimuthal discontinuity (along the north mark) and to track and resolve three closely spaced aircraft within this area.

· Conflict 2: This conflict involves three aircraft, one flying south from inside the zenith cone when its path is intersected at a common point in time by two other aircraft. There is a vertical separation of 600 feet between the paths of the three aircraft. The object of this conflict is to test the sensor’s ability to resolve and track 3 closely spaced aircraft, one of which has recently exited from the zenith cone.

· Conflict 3: This conflict involves four aircraft with vertical separation of 600 feet, whose paths simultaneously intersect at a common point. The objective of this conflict is to test the sensor’s ability to track and resolve four closely spaced aircraft.

· Zenith Cone Crossing: A target flying inbound on a radial at zero degrees enters the zenith cone, and then exits on an outbound radial at 180 degrees. The objective of this maneuver is to observe the sensor’s tracking response to targets flying through the zenith cone.

The targets in group 1 are performing maneuvers as described below:

· Target 1 is flying directly south on a radial at zero degrees, beginning at a range of approximately 8 NMI. It has a constant velocity of approximately 185 knots, and a constant altitude of 14400 feet. It enters, then exits the zenith cone, continuing southbound on a radial at 180 degrees and ends at a range of approximately 21 NMI.

· Target 2 is flying at an altitude of 15600 feet and a velocity of approximately 300 knots. It begins at a range of approximately 9 NMI and an azimuth of 328 degrees with a heading of approximately 125 degrees. As it approaches an azimuth of nearly 90 degrees, it executes a turn to the right to a heading of approximately 235 degrees. At an approximate range of 10 NMI and azimuth of 198 degrees, it executes a turn to the left to a heading of approximately 120 degrees. It continues on this heading until it ends at an approximate range of 24 NMI and azimuth of 150 degrees.

· Target 3 is flying at an altitude of 15000 feet and a velocity of approximately 300 knots. It begins at a range of approximately 9 NMI and an azimuth of 30 degrees with a heading of approximately 240 degrees. As it approaches an azimuth of 280 degrees, it executes a turn to the left to a heading of approximately 130 degrees. At an approximate range of 10 NMI and azimuth of 162 degrees, it executes a turn to the right to a heading of approximately 243 degrees. It continues on this heading until it ends at an approximate range of 23 NMI and azimuth of 212 degrees.

· Target 4 is flying directly East at a constant velocity of 204 knots and a constant altitude of 16200 feet. It begins at a range of approximately 17 NMI and an azimuth of 216 degrees. The target ends at approximately 18 NMI and 140 degrees.

Figure 34: STS Scenario Target Group 1 Waypoints (in Cartesian coordinates) for the targets in group 1 are provided in Table 33; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Table 33: Waypoints for Targets in Group 1 of STS Scenario

02:33

02:41

04:04

05:43

05:47

06:42

06:46

07:45

08:32

09:46

10:32

STS Scenario Target Group 2: Maneuvers in the Zenith Cone Target group 2 consists of two ATCRBS targets that are inside the zenith cone at the same time on the flight paths described below and illustrated in Figure 35 (labels in the figure indicate the start point for each target).

Figure 35: STS Scenario Target Group 2

· Target 1 has a non-discrete Mode 3/A code and is flying at a constant velocity of approximately 160 knots and constant altitude of 5200 feet. It enters the zenith cone on a heading of approximately 53 degrees. While inside the zenith cone, this target executes a right turn and exits on a heading of approximately 130 degrees. The objective of this target is to observe tracker functionality for a target that turns inside the zenith cone. Waypoints (in Cartesian coordinates) for this target and their associated times (in MM:SS format, referenced to the start time of the scenario) are provided in Table 34.

Table 34: Waypoints for Target 1 of Target Group 2 of STS Scenario

· Target 2 has a discrete Mode 3/A code and maintains a constant velocity of approximately 300 knots and a constant heading throughout its life (note that Figure 35 shows this target as turning on a tangential path around system center, this is merely a by-product of the scenario generator plot function, the target actually flies a straight path). It maintains an altitude of 12200 feet as it enters and passes approximately half way through the zenith cone, then begins a descent to 10000 feet. The objective of this target is to observe tracker functionality for a target that changes altitude inside the zenith cone. Waypoints (in Cartesian coordinates) for this target and their associated times (in MM:SS format, referenced to the start time of the scenario) are provided in Table 35.

Table 35: Waypoints for Target 2 of Target Group 2 of STS Scenario

STS Scenario Target Group 3: Parallel Flight with Intersecting Target Target group 3 consists of three targets with the same non-discrete Mode 3/A code, two of which are flying parallel to each other at the same flight level, while the third flies a path that intersects their paths three times with an altitude separation of 600 feet. At the point of each intersection, the two aircraft involved arrive at a common point at nearly the same time. The objective of this target group is to assess the sensor’s ability to resolve conflict situations in a potentially linked track situation. Figure 36 shows the paths of these targets with labels indicating the start point of each target. The path of each target is described below:

· Target 1 is an ATCRBS target with a constant velocity of approximately 300 knots and a constant heading of 180 degrees at an altitude of 12000 feet.

· Target 2 is a Mode S target with a constant velocity of approximately 313 knots and a constant heading of 180 degrees at an altitude of 12000 feet.

· Target 3 is a Mode S target with a velocity of approximately 450 knots and a constant altitude of 12600 feet. It travels on a heading of approximately 130 degrees through the first intersection with each of the other aircraft, then makes a right turn to a heading of approximately 245 degrees through the second intersection with the other aircraft, before making a left turn to a heading of approximately 130 degrees as it intersects the paths of the other aircraft for a third time.

Waypoints (in Cartesian coordinates) for the targets in group 3 are provided in Table 36; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Table 36: Waypoints for Targets in Group 3 of STS Scenario

3:09

3:35

4:35

4:59

5:53

8:05

11:03

Figure 36: STS Scenario Target Group 3 STS Scenario Target Group 4: Interleave/Overlap Targets Target group 4 consists of 2 ATCRBS targets with discrete Mode 3/A codes containing the octal digits 1, 3, 5, and 7, where one is the reverse order of the other. Target 1 flies at a constant velocity of 100 knots, a heading of 270 degrees, and a constant altitude of 20100 feet. Target 2 maintains a constant altitude of 19500 feet throughout the scenario. The paths of these targets are such that they are always on the same azimuth. They begin with a slant range difference that is equivalent to the free-space length of an ATCRBS reply (20.3 µs x speed of light), or 19,966.493 feet; this slant range difference ensures that the replies received from the targets will not interfere with each other for almost 30 scans at the start of the scenario. As the scenario progresses, the slant range of Target 2 is reduced each scan (4.8 seconds) to a value that is equivalent to the current slant range of Target 1 minus an increasing integer multiple of one-fourth of the free space distance of the spacing between each pulse in an ATCRBS reply ((1.45 µs ÷ 4) x speed of light), or 356.545 feet. This allows Target 2’s replies to walk across Target 1’s replies such that the pulses alternate between interleaved and overlapped situations at the receiver input. Target 2’s slant range continues to decrease until its replies have completely walked across those of Target 1 and the slant range difference between the two targets has increased to approximately 19,100 feet. Target 2 then turns and its slant range begins to increase in the same manner as it decreased until the slant range difference between the two targets is approximately the same as it was at the beginning of the scenario. The objective of this target group is to assess the sensor’s ability to track two targets through an extended situation of overlapping and interleaved replies. The paths of these targets are illustrated in Figure 37 with labels indicating the start point of each target. Waypoints (in polar coordinates) for the targets in group 4 are provided in Table 37; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Figure 37: STS Scenario Target Group 4

Table 37: Waypoints for Targets in Group 4 of STS Scenario

STS Scenario Target Group 5: Parabolic ATCRBS Tracks Target group 5 consists of 2 ATCRBS targets with unique, non-discrete Mode 3/A codes flying mirrored parabolic paths whose closest points of approach are approximately 750 feet. Both targets maintain an identical flight level throughout the scenario. The objective of this target group is to assess the sensor’s ability to resolve a conflict in which ATCRBS targets may swap responses in the sensor. The paths of these targets are illustrated in Figure 38 with labels indicating the start point of each target. Waypoints (in Cartesian coordinates) for the targets in group 5 are provided in Table 38; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Figure 38: STS Scenario Target Group 5 Table 38: Waypoints for Targets in Group 5 of STS Scenario

STS Scenario Target Group 6: Parabolic Mode S Tracks Target group 6 consists of 2 Mode S targets with unique, non-discrete Mode 3/A codes flying mirrored parabolic paths whose closest points of approach are approximately 750 feet. Both targets maintain an identical flight level throughout the scenario. The objective of this target group is to assess the sensor’s ability to resolve a conflict in which Mode S targets may swap responses in the sensor. The paths of these targets are illustrated in Figure 39 with labels indicating the start point of each target. Waypoints (in Cartesian coordinates) for the targets in group 6 are provided in Table 39; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Table 39: Waypoints for Targets in Group 6 of STS Scenario

Figure 39: STS Scenario Target Group 6 STS Scenario Target Group 7: Overtaking Pattern Target group 7 consists of two ATCRBS targets with unique, discrete, and complementary Mode 3/A codes (e.g. 1357 and 6420, 1201 and 6576, 1234 and 6543, etc.). Both targets fly along the same path with an altitude separation of 600 feet. Target 1 flies at a constant velocity of approximately 500 knots and overtakes Target 2, which is flying at a constant velocity of approximately 450 knots. The objective of this target group is to assess the sensor’s ability to track overtaking targets with unique, discrete, complementary Mode 3/A codes. The paths of these targets are illustrated in Figure 310 with labels indicating the start point of each target.

Figure 310: STS Scenario Target Group 7 Waypoints (in Cartesian coordinates) for the targets in group 7 are provided in Table 310; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Table 310: Waypoints for Targets in Group 7 of STS Scenario

STS Scenario Target Group 8: Multiple Intersecting Paths Target Group 8 consists of two Mode S targets with unique, discrete Mode 3/A codes. The targets are flying mirrored zig-zag patterns that intersect each other at five locations with approximate angles of intersection of 30 degrees. There is a 700 foot altitude difference between the two targets. The objective of this target group is to assess the sensor’s ability to track closely spaced targets through multiple conflict situations. The paths of these targets are illustrated in Figure 311 with labels indicating the start point of each target. Waypoints (in Cartesian coordinates) for the targets in group 8 are provided in Table 311; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Figure 311: STS Scenario Target Group 8 Table 311: Waypoints for Targets in Group 8 of STS Scenario

STS Scenario Target Group 9: 1g Turns Target group 9 consists of two Mode S targets with unique, discrete Mode 3/A codes. Both targets start on an inbound radial at 270 degrees at a constant velocity of 250 knots with a time offset of 50 seconds. Target 1 performs a 1g turn in a counter-clockwise direction as it approaches the zenith cone at an altitude of 500 feet. Target 2 performs a 1g turn at an identical altitude, but in a clockwise direction. Both targets reach a minimum range of approximately 1 NMI while performing their turns. The objective of this target pair is to assess the sensor’s ability to track targets making 1g turns at close range. The paths of these targets are illustrated in Figure 312 with labels indicating the end point of each target. Waypoints (in Cartesian coordinates) for the targets in group 9 are provided in Table 312; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Table 312: Waypoints for Targets in Group 9 of STS Scenario

Figure 312: STS Scenario Target Group 9 STS Scenario Target Group 10: 3g Turns at 2 NMI Target group 10 consists of two Mode S targets with matching discrete Mode 3/A codes. Both targets start on an inbound radial at 0 degrees at a constant velocity of 400 knots with a time offset of 50 seconds. Target 1 performs a 3g turn in a clockwise direction as it approaches the zenith cone at an altitude of 700 feet. Target 2 performs a 3g turn at an identical altitude, but in a counter-clockwise direction. Both targets reach a minimum range of approximately 2 NMI while performing their turns. The objective of this target pair is to assess the sensor’s ability to track targets making 3g turns at close range. The paths of these targets are illustrated in Figure 313 with labels indicating the end point of each target. Waypoints (in Cartesian coordinates) for the targets in group 10 are provided in Table 313; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Figure 313: STS Scenario Target Group 10 Table 313: Waypoints for Targets in Group 10 of STS Scenario

STS Scenario Target Group 11: 3g Turns at 5 NMI Target group 11 consists of two Mode S targets with unique, discrete Mode 3/A codes. Both targets start on an inbound radial at 0 degrees at a constant velocity of 400 knots with a time offset of 50 seconds. Target 1 performs a 3g turn in a clockwise direction, reaching a minimum range of approximately 5 NMI while executing the turn. Target 2 performs a 3g turn in a counter-clockwise direction, also reaching a minimum range of approximately 5 NMI while executing the turn. Both targets are at an altitude of 1200 feet. The objective of this target pair is to assess the sensor’s ability to track targets making 3g turns at 5 NMI. The paths of these targets are illustrated in Figure 314 with labels indicating the end point of each target. Waypoints (in Cartesian coordinates) for the targets in group 11 are provided in Table 314; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Figure 314: STS Scenario Target Group 11 Table 314: Waypoints for Targets in Group 11 of STS Scenario

STS Scenario Target Group 12: Decelerating and Accelerating Target Target group 11 consists of a single Mode S target with a discrete Mode 3/A code flying a straight path from West to East at a constant altitude. The target starts with a velocity of approximately 650 knots, then decelerates to approximately 250 knots, then accelerates back to 650 knots. The objective of this target is to assess the sensor’s ability to track a rapidly decelerating and accelerating target. The path of this target is illustrated in Figure 315 with the label indicating its start point. Waypoints (in Cartesian coordinates) for the target in group 12 are provided in Table 315; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Table 315: Waypoints for Target in Group 12 of STS Scenario

Figure 315: STS Scenario Target Group 12 STS Scenario Target Group 13: Mode 2 Targets Target group 13 consists of 2 aircraft with discrete Mode 3/A codes that reply to Mode 2 interrogations with unique Mode 2 codes. Target 1 is a Mode S target that flies a clockwise tangential pattern from 0 to 90 degrees at a range of 48 NMI and a constant velocity of approximately 250 knots. Target 2 is an ATCRBS target that flies a counter-clockwise tangential pattern from 90 to 0 degrees at a range of 29 NMI and a constant velocity of approximately 150 knots. Target 1 is climbing at a constant rate of approximately 500 feet/sec, while Target 2 is descending at a constant rate of approximately 500 feet/sec. The objective of this target group is to assess the sensor’s ability to perform Mode 2 interrogations of both Mode S and ATCRBS targets and to accurately decode the associated replies. The paths of these targets are illustrated in Figure 316 with labels indicating the start point of each target. Waypoints (in polar coordinates) for the targets in group 13 are provided in Table 316; the times associated with these waypoints are referenced to the start time of the scenario in MM:SS format.

Figure 316: STS Scenario Target Group 13

Table 316: Waypoints for Targets in Group 13 of STS Scenario