scope:

Personal Locator Beacons

This document contains minimum requirements for the functional and technical performance of Personal Locator Beacons (PLBs) operating in the 406.0 to 406.1 MHz band through polar-orbiting, medium earth orbiting and geostationary satellite systems. A 406 MHz PLB designed and manufactured to the standards contained in this document meets the PLB portion of the Cospas-Sarsat ¹ System developed and implemented by the Cospas-Sarsat Partners (the Russian Federation, Canada, France, and the United States) as wel l as the environmental requirements considered necessary for PLB use.

System overview

Cospas-Sarsat is an international system that uses low altitude, near -polar orbiting, medium earth orbiting and geostationary satellites that assist in detecting and locating activated 406 MHz satellite beacons. The Russian Federation provides COSPAS payloads aboard Russian navigation spacecraft. In addition to weather and environmental sensors, SARSAT payloads, provided by Canada and France, are carried aboard the United States National Oceanic and Atmospheric Administration National Environmental Satellite Data and Information Service (NOAA, NESDIS) environmental satellites. 406 MHz repeater payloads are now also being deployed on Global Navigation Satellite Systems (GNSS) such as Galileo, Glonass and GPS in medium earth orbits. The COSPAS, SARSAT and GNSS Systems are fully interoperable.

Satellite receiver/processors receive distress signals from PLBs transmitting in the 4 06.0 - 406.1 MHz frequency band. The use of the band is limited by the International Telecommunications Union (ITU) Radio Regulations, Article 5 (Table of Allocations) to low-power satellite EPIRBs ², which include those that are being used with the COSPAS and SARSAT satellite receiver/processors. The Cospas-Sarsat 406 MHz PLB signal consists of a transmission of unmodulated carrier followed by a digital message format that provides identification data, nationality, and (optionally) encoded position data.

Because many of the search and rescue forces presently are not equipped to home on the 406 MHz PLB signal, homing must be accomplished at another frequency. This standard provides for the inclusion of an auxiliary radio-locating device operating at 121.5 MHz or an auxiliary radio-locating device operating at 121.5 MHz and an Automatic Identification System (AIS) transmitter operating in the maritime VHF frequency band.

Local User Terminals (LUTs) process the 406 MHz signal and determine the location of the PLB; the LUT then relays the position of the distress to a Mission Control Center (MCC) where the distress alert and location information is immediately forwarded to an appropriate Search and rescue Point Of Contact (SPOC). The SPOC dispatches Search And Rescue (SAR) forces.

Purpose and intended use

The PLBs are intended to provide individuals in remote areas a means to alert others of an emergency situation and to aid search and rescue personnel locate those in distress. The purpose of the PLB is to alert authorities to a distress situation and the location of the alerting beacon. The PLB consists of a transmitter, an internal GNSS receiver and a battery power source, all contained in an impact resistant watertight case. PLBs are envisioned to be used in two general environments, areas with water (e.g. rivers, lakes, oceans, seas, flooding) and areas without significant water (e.g. deserts, mountains). Therefore, this recommended standard includes two categories of PLBs, Category 1 which must float and Category 2 which is not required to float.

Precedence

In case of any conflicts between this standard and any other document or standard referenced in this standard, this standard takes precedence.

Types of PLB

406 MHz PLBs are divided into two generations, two categories, three classes and three groups as defined below.

Generations

There are two generations of 406 MHz PLBs:

• First Generation Beacons (FGBs) that are designed to comply with C/S T.001 and are tested and approved to C/S T.007; and

• Second Generation Beacons (SGBs) that are designed to comply with C/S T.018 and are tested and approved to C/S T.021.

Categories

There are two categories of PLBs:

• Category 1 PLBs are designed for use in and around water (but in some circumstances can also be used on land) and must float³: and

• Category 2 PLBs are designed principally for use on land (but in some circumstances can also be used in and around water) and are not required to float.

Classes

There are three classes of PLBs:

• Class 0 PLBs are designed for use in extreme climatic conditions and must operate over the temperature range of -55°C to + 70 C;

• Class 1 PLBs are designed for use in arduous climatic conditions and must operate over the temperature range of -40°C to + 55 C; and

• Class 2 PLBs are designed for use in less arduous climatic conditions and must operate over the temperature range of -20°C to + 55°C.

Groups

There are three groups of PLBs:

• Group 1 PLBs shall include a 121.5 MHz homing transmitter

• Group 2 PLBs - reserved for future use

• Group 3 PLBs shall include a 121.5 MHz homing transmitter and an AIS transmitter

GNSS Navigation Devices

All types of PLBs designed to meet this standard shall include beacon position data, obtained from a GNSS navigation device internal to the PLB and shall comply with the requirements of Annex G (Internal Navigation Device Test Methods) .

Combinations of PLB Generations, Categories, Classes and Groups

Any combination of Generation, Category, Class and Group is permitted by this standard.

Every PLB must comply with the requirements of at least one Generation, one Category, one Class and one Group as defined above.

A PLB cannot be both a Category 1 and Category 2 device, either it floats or it doesn't.

A PLB is only ever approved to one Class, by definition a Class 0 PLB also meets the requirements for a Class 1 and Class 2 PLB and a Class 1 PLB also meets the requirements for a Class 2 PLB.

A PLB can currently only be a Group 1 or Group 3 PLB, a Group 3 PLB may potentially also meet the requirements of a Group 1 PLB.

Any PLB can also include Return Link Service (RLS) capability.

¹ COSPAS - COsmicheskaya Sistyema Poiska Avariynych Sudov (Space System for Search of Distressed Vessels) (Russian Federation).

SARSAT - Search and Rescue Satellite-Aided Tracking (Canada, France, and United States).

² An emergency position-indicating radiobeacon (EPIRB) is defined by the ITU Radio Regulation No. 1.93 as a station in the mobile service the emissions of which are intended to facilitate search and rescue (SAR) operations. A satellite EPIRB is also defined by the ITU Radio Regulations No. 1.94 as an earth station in the mobile -satellite service the emissions of which are intended to facilitate SAR operations. For the purposes of the ITU Radio Regulations a PLB is understood to be a type of EPIRB.

³ Floating can be achieved by either inherent buoyancy or by a permanently attached flotation device (i.e. cannot be disconnected without the use of tools). A flotation aid such as a pouch, bag or floating key fob does not count unless it is permanently attached to the PLB. Category 1 PLBs can either be designed to operate while floating in water or when attached to items of personal LSA, further details are provided in A.1.10