Figure 1. Situation of the archaeological site Empuries showing the assumed urban subdivision into individual insulae and the surveyed areas Grid AA and AB, marked in red. Full wave-field recording: STREAM X at Empuries (Girona, Spain) Alexandre Novo 1 , Roger Sala 2 , Gianfranco Morelli 1 , Juerg Leckebusch 3 and Joaquim Tremoleda Trilla 4 1 Geostudi Astier, via Nicolodi, 46, 57100 Livorno, Italy. novo@geoastier.it, gf.morelli@tin.it 2 SOT Prospection, Emeterio Escudero, 76B Sant Cugat del Vallès, 08198 Barcelona, Spain. roger_sala_bar@yahoo.es 3 terra vermessungen ag, Ahornweg 3, 5504 Othmarsingen, Switzerland 4 MAC (Archaeological Museum of Catalonia), C/ Puig i Cadafalch s/n. 17130 Empúries-l'Escala, Spain Abstract— GPR array systems consisting of a large number of closely-spaced antennas represent a new revolution for archaeo- logical prospection. This work presents a novel modular system which shows unprecedented speed of areal coverage together with precise images of the subsurface structures. Results of this case study highlight the effectiveness and robustness of the meth- od for archaeological investigations of large areas. A portion of the Roman site of Empuries was surveyed as an example of forthcoming archaeological geophysics. Keywords-component; Ground Penetrating Radar, Multi- channel, Antenna array, Archaeology I. INTRODUCTION GPR has been one of the most utilized tools for archaeolo- gical prospection in the last two decades [1] due to its high resolution data and 3D visualization capabilities. Slowness of data acquisition with single channel systems has resulted in a standard of coarse profile spacing and interpolation to fill in the data gaps [2]. Multi-channel systems speed up data acquisition and allow full wave-field recording at the same time [3]. Even though the first introduction of multi-channel GPR systems date back more than 15 years [4], the acceptance of multi-channel record- ing was limited by the quality of the data and complex data processing [5]. However, recent advances in hardware and software have definitely pushed the technology a step forward [6]. In this work we present a complete GPR solution for full- wave field recording. The novel array system called STREAM X has been designed and tested during the last two years to specifically survey archaeological sites. There are several other array systems on the market available today which have pro- duced some good [7][8] but also some bad results [9]. In February 2011 a survey with a STREAM X was per- formed to cover 1 hectare of the important archaeological site Empuries in Spain. The main aim was to show the capabilities of the system as an efficient tool for high-resolution archaeo- logical prospection. II. EMPURIES SITE Empuries is the only archaeological site on the Iberian Pen- insula where there are remains of a Greek and a Roman city at the same place. The Greek occupation started in the 6th century BC. They first occupied the Sant Martí d’Empúries promontory and the land situated south of the natural port where they de- veloped a new center known as Neapolis. After the Romans conquered the Iberian peninsula at the beginning of the 1st cen- tury BC they built a new city with a regular plan covering 23 ha (Fig. 1). The Greek and Roman city coexisted all the time and there was even a third ethnic component from the Iberians.