Cosite Interference Mitigation in Phased Arrays SBIR Topic 101104

1
Co-site Interference Mitigation in Phased
ArraysSBIR Topic 101-104

• Naval Undersea Warfare Center, Division Newport

2
Outline

• SBIR Topic N101-104 Objective
• System Technical Information
• Wideband Receive Array
• Narrowband Transmit Array
• General Information
• Notional Antenna Information

3
SBIR Topic N101-104 Objective

• To develop method(s) to address the effects and
  impacts of co-site interference with respect to
  phased array technology at X-band where transmit
  and receive bands are close in frequency.
• Of particular concern is the communications
  degradation resulting from in-band (Narrowband
  X-band) transmit signals impacting the Wideband
  Receive array performance.
• Consult the SBIR website for a complete
  description of the topic
• http//www.dodsbir.net/sitis/

4
The following information is provided as
guidance for the overall notional antenna
communications system in which any developed
co-site interference mitigation method or
technology would need to interface.
SBIR Technical Information
5
Wideband Receive Array

• Frequencies Performance across the 7-22 GHz
  frequency band, with emphasis on the 7.25-7.75
  GHz and 20.2-21.2 GHz sub-bands.
• Gain-to-Noise Temperature Ratio A 100 in2
  aperture size is presented as a notional
  reference aperture area for characterizing G/T
  per unit area. G/T requirements are for bore
  sight (unscanned) performance.
• K-Band G/T shall be greater than 6.3 dB/K
  (notional) for a nominal 100 in2 aperture across
  the 20.2-21.2 GHz operating band.
• X-Band G/T shall be greater than -0.5 dB/K
  (notional) for a nominal 100 in2 aperture across
  the 7.257.75 GHz operating band.
• Other frequencies For frequencies between 7-22
  GHz but outside the above bands, reduced
  performance at other frequencies in order to
  maximize performance in the SATCOM bands, may be
  considered.

6
Narrowband X-band Transmit Array

• Frequencies Performance across the 7.9 8.4
  GHz frequency band.
• Effective Isotropic Radiated Power (EIRP)
  Required EIRP of the transmit array shall be
  46.5 dBW (notional) when operating at boresight
  (no scan loss).

7
General Information

• Scan Angle and Scan Loss Electronic beam
  steering is required to establish satellite
  connectivity and track the beam. The arrays
  shall be capable of a maximum scan angle of 70.
• Antenna Polarization Antenna polarization
  performance (axial ratio) for the arrays shall
  meet the polarization and axial ratio
  requirements stated in MIL-STD-188-164A.
• Co-site Interference Arrays shall be capable of
  operating at specified performance levels as part
  of a full-duplex communications link with
  co-located narrowband transmit arrays emitting
  in-band signals with other systems. Array shall
  also meet the requirements of MIL-STD-461F and
  MIL-STD-464.
• Size It is imperative that the design and
  fabrication of the technology to mitigate co-site
  interference be as thin and small as possible.

8
Notional Antenna Layout

• All arrays integrated into flat panel antenna
  housing
• Wideband Receive array X-K band
• Narrowband Transmit arrays X-band, Ka-band,
  Q-band
• Frequencies to be supported include
• X-band (DSCS, WGS)
• K/Ka-band (GBS, WGS)
• K/Q-bands (EHF, MILSTAR, AEHF)
• Other components located in housing
• Array power supplies/ controllers
• Array cooling system
• RF to Fiber conversion
• Fiber optic rotary joint