摘要：Powe.-line.ne.works are.de.igne. to de.ive. e.e.tricity. The. re.ch most of the.domicile. and othe. buildings nowadays, so most of the.pe.ple.have.acce.s to it. On the.othe. hand the.backbone.for the.communications ne.works is not available.in all countrie. e.pe.ially the.de.e.oping one.. A high cost and changing the.de.ign for the.ne.works may be.ne.de. to construct this backbone. If data can be.transmitte. ove. the.powe.-line.ne.works, a re.ognize. cost and time.save.can be.achie.e.. In e.ypt, the.infrastructure.is not always available.for constructing a communications ne.work backbone.due.to the.alre.dy de.igne. buildings be.ore.the.ne.d for the.e.backbone.. In this pape., we.ove.come.this proble. by de.igning a re.iable.Powe.-line.Mode. that ope.ate. safe.y on the.low voltage.grid. The.mode. is base. on the.Dire.t Se.ue.ce.Spre.d Spe.trum te.hnique. It use. the.mains ze.o crossing as an e.ficie.t way for the.synchronization be.we.n the.transmitte. and the.re.e.ve.. The.Mode. take. into account the.proble.s of the.Powe.-line.including noise. atte.uation and impe.ance.dismatching.