In　this　paper,　we　investigate　a　metamaterial-inspired　small　rectenna　(rectifying　antenna)　system　for　microwave　energy　harvesting　and　wireless　power　transfer　at　5.8　GHz.　We　also　study　the　received-power　maximization　technique　using　an　array　of　antennas　connected　to　a　single　load　by　an　optimal　RF　power　combiner.　This　investigation　is　done　both　in　simulation　and　experiment.　The　power　combiner　is　embedded　between　the　metamaterial-inspired　antennas　and　the　load　(including　rectifier)　for　maximizing　the　power,　harvested　by　the　input　antennas　and　to　deliver　it　to　the　load　in　the　most　optimal　way.　Moreover,　we　design　and　test　proof-of-concept　prototypes　of　the　main　components　of　the　investigated　energy　harvesting　systems.　The　similarity　between　the　simulation　and　the　experimental　results　also　confirms　our　method　of　investigation.