DVB-S Signal Tracking Techniques for Mobile Phased Arrays

Abstract

Abstract-A system that uses adaptive beamforming techniques for mobile Digital Video Broadcasting Satellite (DVB-S) reception is proposed in this paper. The purpose is to enable DVB-S reception in moving vehicles. Phased arrays are able to electronically track the desired signal during dynamic behaviour of the vehicle the array is mounted on.The proposed system uses blind beamforming to adapt the array steering vector to changing signal (conditions and) directions. Movement of the vehicle, the phased array is mounted on, leads to modulus and phase deviations at the beamformer output. An extended version of the Constant Modulus Algorithm (CMA) algorithm is used to adapt the steering vector weights to compensate for those deviations.For simulation of the proposed system a model of vehicle dynamics is used to generate realistic antenna data. Simulation of the proposed system based on this antenna data shows appropriate corrections for modulus and phase deviations.

Adaptive Beamforming Using the Reconfigurable MONTIUM TP

“…As shown in [13], the update rate of the beam control algorithms can be decreased considerably before symbol errors start to occur. Therefore, for the remainder of this article we assume a beam update rate of ρ = 1 250 = 0.004 updates per antenna sample.…”

Mobile satellite reception with a virtual satellite dish based on a reconfigurable multi-processor architecture

“…For larger angles, an initial rotation over AE p 2 should be applied, which can be realized with a set of equations that is slightly different from Eqs. ( 9)- (11). The MONTIUM TP implementation of the initial equations is comparable to the mapping presented for the regular CORDIC operations.…”

“…3). A Root-Raised-Cosine (RRC) filter is used as Matched Filter, and can be implemented by a 25-tap Finite Impulse Response (FIR) filter [5].…”

“…Moreover, since antenna snapshots are sampled at a rate that is orders of magnitude higher than the rate of movement of the transmitter, operating the Extended CMA algorithm once every few antenna snapshots considerably saves in processing requirements. Typically, the update rate of the Extended CMA algorithm can be in the order of hundreds times lower than the sample rate [11]. For each Extended CMA update, only one snapshot is used and the remaining snapshots are not used.…”

The problem with time in mixed continuous/discrete time modelling

“…The path length from a transmitter to each antenna element is different, resulting in a different time delay for each antenna signal. To validate an adaptive steering algorithm [1] we have developed, the modelled time delays must be exact.…”