Benthowave Instrument Inc.

BENTHOWAVE INSTRUMENT INC. Acoustic Transducer & System 

Discrete Line Array: Spatial Filtering

BII-7210 series discrete line arrays are designed for uses in spatial filtering of passive Sonar: 1D linear array, 2D Planar array and 3D cylindrical array, which enhances the detectability, resolution and directional measurement of underwater plane wave signals.

With multiple BII-7120s as array elements, the planar array and cylindrical (or sector) array can be set up, and the beam in main response axis can be steered in horizontal and vertical. Multiple beams at different directions can also be formed simultaneously with digital beamforming technology. Side-lobe level can be suppressed with array shading.

Multiple BII-7120s can also be stacked in length to extend the array length and therefore to reduce the along-length beam angle. Multiple BII-7120s can also be stacked in width to extend the array width and therefore to reduce the along-width beam angle.

It is recommended to use BII-7210 series above 10kHz. For the array below 10kHz, it is recommended to use discrete hydrophones as array elements.

BII-7210    Discrete Line Array: Spatial Filtering

Suggested Application  
Line Array
Passive Sonar
Bioacoustic Research
Acoustic Imaging
Acoustical Positioning
Array Element of Planar & Cylindrical Array
Underwater Communication
Target Tracking, Target Angle Estimation
Education on Array Signal Processing
Underwater Robotic and Vehicle (ROV, AUV, UUV)
Rectangular Aperture
Elements: up to 64
No grading Lobes
±90º Beam Steering
10 to 240kHz, Customized
Support Amplitude Shading
Related Products  
BII-1000 Preamplifier BII-7680 Wide Beam Transducer


Discrete Line Array Discrete Line Array
BII-7210 Series BII-7211 BII-7212 BII-7213 BII-7214
Usable Frequency f: 10 to 50kHz 10 to 70 kHz 10 to 120 kHz 10 to 240 kHz
Array Element Number: 20 27 46 64
Element Spacing along Length: 15mm 10.7mm 6.2mm 3.2mm
Along-Length Beamwidth (-3dB):
272º*kHz/f 272º*kHz/f 272º*kHz/f 384º*kHz/f
Along-Width Beamwidth (-3dB): 2000º*kHz/f 2800º*kHz/f 3600º*kHz/f 4800º*kHz/f
Steering of Along-Length Beam: ±90º ±90º ±90º ±90º
Steering of Along-Width Beam: No No No No
Element Capacitance: 0.46nF 0.38nF 0.3nF 0.25nF
Size (LxWxD): 300x50x26mm 300x40x26mm 300x30x26mm 220x25x26mm
Miscellaneous: BII-7210 Series Hydrophone
Customization: Customized usable frequency, element spacing, element number and beamwidth are available.
Array Geometry: Line Array 
Array Aperture: Rectangular
Sidelobe Level: ≤ -13.3dB (without amplitude shading)
Grating Lobes: No
Sensitivity of Element: -197.8 dBV/µPa
Signal Loss: Signal Loss over Extension Cable (dB) = 20*log[Ch/(Ch+Cc)];
Ch: Element Capacitance; Cc: Capacitance of Extension Cable.
Shielded sable is of 60pF/meter, Coax is of 100pF/m, roughly.
Output Signal Type: Single Ended Output (SE)
Digital Beamformer: Not included.
Maximum Operating Depth: 100m
Mounting Options: 1. Free Hanging: (FH)
2. End-face Mounting: (EFM)
Click Transducer and Hydrophone Mounting for more detailed information on mounting/installation.
Cable Length: 1. Default: 6m for Free Hanging; 0.2m for End-face Mounting.
2. Customized length up to 20m for free hanging; up to 0.5m for End-face Mounting.
Cable for Free Hanging: 1. Default: Shielded cable with two conductors (ΦD=3.6mm) (SC36)
2. Coax (ΦD=2.8mm) (Coax)
Cable for End-face Mounting: Coax: (Coax)
Connector: 1. Wire Leads (WL)
2. BNC Male (BNC)
3. Underwater Mateable Connector (UMC)
Operating Temperature: -10°C to +60°C
Storage Temperature: -40°C to +60°C
How to Order: Click How to Order.
Hydrophone Wiring: Click Hydrophone Wiring for detailed wiring information.

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