JRC, JHS-182 Class A Automatic Identification System (AIS)

The JRC JHS-182 AIS is a shipborne Class A Automatic Identification System (AIS) designed to improve maritime safety by enabling vessels to automatically exchange navigational and identification data over VHF radio.

The JHS-182 operates as a transponder, meaning it both:

Transmits the vessel’s own data (position, speed, heading, identity)
Receives similar data from nearby ships and coastal stations

This continuous data exchange allows ships and authorities to maintain real-time awareness of surrounding traffic, significantly reducing the risk of collision.

Technical Specification

📡 General Specifications

Type: Class A AIS (IMO compliant)
Frequency Range: 156.025 – 162.025 MHz
AIS Channels:
- AIS 1: 161.975 MHz
- AIS 2: 162.025 MHz
Channel Spacing: 25 kHz / 12.5 kHz
Frequency Accuracy: ±3 × 10⁻⁶

📶 Transmission & Modulation

Output Power: 12.5 W (high) / 2 W (low)
Type of Emission: F1D, F2B
Modulation: GMSK / FSK
Access Method: SOTDMA (Self-Organized TDMA)

🔌 Electrical Specifications

Power Supply:
- 24 V DC (−10% to +30%)
- Optional AC supply: 100–240 V via PSU
Current Consumption:
- Transmitting: ~4.5 A max
- Receiving: ~1.5 A max