P. Jorna

Novel Ring Resonator-Based Integrated Photonic Beamformer for Broadband Phased Array Receive Antennas—Part I: Design and Performance Analysis

A novel optical beamformer concept is introduced that can be used for seamless control of the reception angle in broadband wireless receivers employing a large phased array antenna (PAA). The core of this beamformer is an optical beamforming network (OBFN), using ring resonator-based broadband delays, and coherent optical combining. The electro-optical conversion is performed by means of single-sideband suppressed carrier modulation, employing a common laser, Mach-Zehnder modulators, and a common optical sideband filter after the OBFN. The unmodulated laser signal is then re-injected in order to perform balanced coherent optical detection, for the opto-electrical conversion. This scheme minimizes the requirements on the complexity of the OBFN, and has potential for compact realization by means of full integration on chip. The impact of the optical beamformer concept on the performance of the full receiver system is analyzed, by modeling the combination of the PAA and the beamformer as an equivalent two-port RF system. The results are illustrated by a numerical example of a PAA receiver for satellite TV reception, showing that - when properly designed - the beamformer hardly affects the sensitivity of the receiver.

Conformal phased array with beam forming for airborne satellite communication

For enhanced communication on board of aircraft novel antenna systems with broadband satellite-based capabilities are required. The installation of such systems on board of aircraft requires the development of a very low-profile aircraft antenna, which can point to satellites anywhere in the upper hemisphere. To this end, phased array antennas which are conformal to the aircraft fuselage are attractive. In this paper two key aspects of conformal phased array antenna arrays are addressed: the development of a broadband Ku-band antenna and the beam synthesis for conformal array antennas. The antenna elements of the conformal array are stacked patch antennas with dual linear polarization which have sufficient bandwidth. For beam forming synthesis a method based on a truncated singular value decomposition is proposed.

Broadband optical beam forming for airborne phased array antenna

For enhanced communication on board aircraft, novel antenna systems with broadband satellite-based capabilities are required. The technology will enhance airline operations by providing in-flight connectivity for flight crew information and will bring live TV and high-speed Internet connectivity to passengers. The installation of such systems on board aircraft requires for aerodynamic reasons the development a very low-profile aircraft antenna, which can point to satellites anywhere in the upper hemisphere. Major keystones for the success of steerable low-profile antennas are multi-layer printed circuit boards (PCBs) with an array of broadband antenna elements, and compact micro-wave systems with appropriate beam steering capabilities. The present paper describes the development of a prototype 8x1 optical beam forming network using cascades of optical ring resonators as part of a breadboard Ku-band phased array antenna.

Development of dual-frequency airborne Satcom antenna with optical beamforming

For enhanced communication on board aircraft, novel antenna systems with broadband satellite-based capabilities are required. The amount of data agglomerated over a range of passenger services (VoIP, Web, Email, SMS, MMS) and over a range of flights, appears highly asymmetrical. The inbound traffic is about 5 times higher than the outbound. The inbound traffic requires the availability of a broadband Ku-band antenna in receive mode only. The outbound traffic services can be supplied by the Inmarsat SBB link, which requires the installation of an L-band transmit antenna. In order to avoid both the installation of L-band antenna and Ku-band antenna, the concept of a hybrid dual-frequency antenna operating both L-band and Ku-band is being explored in this paper.

Development of the SANDRA antenna for airborne satellite communication

Novel avionics communication systems are required for increasing flight safety and operational integrity, for optimizing economy of operations and for enhancing passenger services. One of the key technologies to be developed is an antenna system that will provide broadband connectivity within aircraft cabins at an affordable price. This paper describes the development of an electronically steered Ku-band phased array antenna with low aerodynamic profile. The antenna front-end consists of at least 1800 antenna elements, of which the beam has to be steered continuously to geostationary satellites. Best performance for the beam steering is expected from a hybrid architecture with small sub-apertures having their local own beamformers (using phase shifters). The beamformer to steer the sub-apertures of the entire antenna uses True Time Delays with an optical ring resonator. 1 2