Description
The objective of the activity is to design and validate the baseband receiver of a user terminal to compensate for beam squint adopting equalisation techniques. The goal is to maintain the end-to-end performance for wideband carrier, large phased arrays and large scanning angles.Targeted Improvements: Up to 3 dB link quality improvement for wideband carriers (500 MHz or larger) and large scan angles of representative active antenna array operating at Ka-Band. Description: In an active direct radiating array antenna, where beamforming is carried out with phase shifters, different signal frequencies require different phase shifts in order to steer the beam with a certain angle with respect to the boresight. This frequency dependent phase shift will lead to signal distortion and performance loss especially at high carrier frequency, wideband signals and large scan angle. In principle the issue can be solved by implementing beamforming by means of time delay. However, the complexity associated with such implementation (True Time Delay) leads to solutions and products that are not suitable for the consumer market. Alternatively, an analogue phase-only beamforming implementation may be the preferred approach by mainly reducing the complexity, enabling solutions for the consumer market. This activity will investigate signal processing techniques at the receiver for reducing the losses caused by beam squinting for user terminals with phase-only beamforming. The target systems include non-geostationary satellite systems operating Ka-Band in the user segment and forward link signal bandwidth above 500 MHz (up to 2 GHz). The return link signal bandwidth is expected to be substantially narrower thus not requiring particular compensation techniques. Spectral efficiencies from up to 4 bps/Hz are expected to be used in the forward link. Work to be performed include Channel model characterisation for representative system scenarios. The frequency selective channel including the effect of non-ideal beamforming of the user terminal, shall be derived as a function of all the key system parameters listed above. A realistic model shall be derived. Definition, design and implementation of the channel equalisation techniques to be assessed in the next task. The activity will also include the assessment of physical layer link performance, the implementation of the selected technique and set-up lab tests to evaluate and quantify the performance gain of the proposed technical with respect to the benchmark. Procurement Policy: C(1) = Activity restricted to non-prime contractors (incl. SMEs). For additional information please go to: http://www.esa.int/About_Us/Business_with_ESA/Small_and_Medium_Sized_En…