This paper proposes an experimental study of the coupling effect of a rectenna array. The rectifying antenna consists of a compact and efficient rectifying circuit in a series topology, coupled with a small metamaterial-inspired antenna. The measurements are investigated in the X plane on the behavior of rectenna array, with series and parallel DC-combining configuration of two and three spaced rectennas from 3cm to 10cm. This study shows that the maximum efficiency is reached for the series configuration, with a resistive load of 10kΩ. The optimal distance is not significant for series or parallel configuration. Then, a comparison between a rectenna array with non-optimal mutual coupling and a more traditional patch rectenna is performed. Finally, a practical application is tested to demonstrate the effectiveness of such small rectenna array. 1. Introduction With the development of very low-power wireless system, numerous researches have focused their attention on the feasibility of powering devices through the harvesting of ambient electromagnetic energy [1]. The main challenges in far field nondirective powering are a result of the low and variable power densities available at the receiving antenna. Therefore, the study deals with the design, optimization and experimental characterization of a compact metamaterial-inspired antenna coupled with a rectifier. Then, to increase DC power over the load, the proposed rectenna has been interconnected to form arrays [2]. This is called DC-combining configuration where the outputs of each rectenna are combined in series, parallel or a hybrid manner. It has the advantages to ease the construction of the rectenna array oppositely to the RF-combining configuration. In RF-combining structure, the RF outputs of each antenna are combined before the rectifier circuit. The RF-combining configuration implies the use of sub-circuit to deal with power leakage and phasing between the antennas. This issue is eliminated when DC-combining is use, but the tradeoff of such configuration, is lower RF-to-DC conversion and the use of several rectifying element. In this paper, we investigate the behavior of rectenna array using electrically small antenna. First, we inquire the effect of mutual coupling on two different DC-combining configuration, series and parallel for a finite number of elements. Then, a comparative study is conduct between a rectenna array and a single rectenna using a conventional patch antenna [3], having the same physical surface area. Last, an application of the rectenna array is tested, where a battery-less temperature sensor is powered over a distance of one meter.