Micromodems in the Field - Multi-System Use
The Micromodem has been used in several situations where there have been multiple vehicles, multiple bottom mounted sensors, multiple ships and buoys all working cooperatively together in one or more frequency bands. The Acoustic Communications Group has hardware solutions for most applications. Please see the simplified scenarios that follow to see if your application is similar.
Micromodems in the Field - Boat to Vehicle
In this scenario, a topside modem kit installed on a small boat or ship communicates via an over the side transducer towfish to an underwater vehicle with modem kit installed.
Typical Equipment Required (assumes 25kHz Mulit-Channel PSK operation):
Topside (i.e. on Boat)
256020 Rack Mountable Deck Box (battery powered dry enclosure) or 252080 RHIB Deck Box (battery powered submersible enclosure)
224001 Transducer Towfish
234052-50ft Cable: Transducer and Array Load Bearing - 50ft Length
211002 Transducer: WH-BT-2
214008 Array: HTI-96-MIN (CM) 4 Element Inline Array
205004-0216 Micromodem Full PSK RFF Stack for 12V Supply and 211002 Transducer
Vehicle (Assumes modem is installed in vehicle electronics bay or similar, we have several stand alone housings available):
205004-0216 Micromodem Full PSK RFF Stack for 12V Supply and 211002 Transducer
211002 Transducer: WH-BT-2
214008 Array: HTI-96-MIN (CM) 4 Element Inline Array
Micromodems in the Field - Boat to Buoy
In this scenario, a topside modem kit installed on a small boat or ship communicates via an over the side transducer towfish to a VSW Modem Buoy with modem kit installed. This application is typically used by the Acoustic Communications Group to measure the performance of the acoustic channel prior to vehicles or sensors getting in the water.
Typical Equipment Required (assumes 25kHz Mulit-Channel PSK operation):
Topside (i.e. on Boat)
256020 Rack Mountable Deck Box (battery powered dry enclosure) or 252080 RHIB Deck Box (battery powered submersible enclosure)
224001 Transducer Towfish
234052-50ft Cable: Transducer and Array Load Bearing - 50ft Length
211002 Transducer: WH-BT-2
214008 Array: HTI-96-MIN (CM) 4 Element Inline Array
205004-0216 Micromodem Full PSK RFF Stack for 12V Supply and 211002 Transducer
Buoy (Maximum Operating Depth 100ft unless in drifter application):
255011-3RB VSW Modem Buoy with (3) Rechargeable Li-Ion Batteries, GPS and 900MHz Freewave
234052-50ft Cable: Transducer and Array Load Bearing - 50ft Length
211002 Transducer: WH-BT-2
214008 Array: HTI-96-MIN (CM) 4 Element Inline Array
205004-0216 Micromodem Full PSK RFF Stack for 12V Supply and 211002 Transducer
Micromodems in the Field - Buoy to Vehicle
In this scenario, a VSW Modem Buoy with modem kit installed communicates to an underwater vehicle with modem kit installed. The user communicates to the buoy via and RF link. The buoy communicates to the vehicle via an acoustic link.
Typical Equipment Required (assumes 25kHz Mulit-Channel PSK operation):
Buoy (Maximum Operating Depth 100ft unless in drifter application):
255011-3RB VSW Modem Buoy with (3) Rechargeable Li-Ion Batteries, GPS and 900MHz Freewave
234052-50ft Cable: Transducer and Array Load Bearing - 50ft Length
211002 Transducer: WH-BT-2
214008 Array: HTI-96-MIN (CM) 4 Element Inline Array
205004-0216 Micromodem Full PSK RFF Stack for 12V Supply and 211002 Transducer
Vehicle (Assumes modem is installed in vehicle electronics bay or similar, we have several stand alone housings available):
205004-0216 Micromodem Full PSK RFF Stack for 12V Supply and 211002 Transducer
211002 Transducer: WH-BT-2
214008 Array: HTI-96-MIN (CM) 4 Element Inline Array
Micromodems in the Field - Buoy to Node to Vehicle
In this scenario, a ship communicates via and RF link to a buoy which communicates acoustically (25kHz) to a bottom mounted node acting as a repeater. The node then communicates acoustically (10kHz) to another bottom mounted node acting as a repeater. The second node then relays the message acoustically (25kHz) to the vehicle. All systems could operate in the same frequency band depending on the relative spacing of the various systems. The dual band concept has worked well in short range cells with long range hops between cells.
Typical Equipment Required (assumes 25kHz (short range) and 10kHz (long range) Mulit-Channel PSK operation):
Buoy (Maximum Operating Depth 100ft unless in drifter application):
255011-3RB VSW Modem Buoy with (3) Rechargeable Li-Ion Batteries, GPS and 900MHz Freewave
234052-50ft Cable: Transducer and Array Load Bearing - 50ft Length
211002 Transducer: WH-BT-2
214008 Array: HTI-96-MIN (CM) 4 Element Inline Array
205004-0216 Micromodem Full PSK RFF Stack for 12V Supply and 211002 Transducer
Bottom Node (Assumes 25kHz is used for short range communication and 10kHz is used for long range communications)
252060 Node, Dual Band, (5x Li-Ion Batteries ~1kWhr)
223508 Cage for Dual Band Node
223049 Transducer: ITC-3013 with Backing Block
211002 Transducer: WH-BT-2
214008 Array: HTI-96-MIN (CM) 4 Element Inline Array
205004-0216 Micromodem Full PSK RFF Stack for 12V Supply and 211002 Transducer
205008-0812 Micromodem Full PSK MF Stack for 12V Supply and ITC-3013 Transducer
205018 Gumstix Interface Board with Gumstix Computer
Vehicle (Assumes modem is installed in vehicle electronics bay or similar, we have several stand alone housings available):
205004-0216 Micromodem Full PSK RFF Stack for 12V Supply and 211002 Transducer
211002 Transducer: WH-BT-2
214008 Array: HTI-96-MIN (CM) 4 Element Inline Array