針對UHF讀寫器設計中,在符合EPC Gen2標準的情況下,對標簽返回的高速數據進行正確解碼以達到正確讀取標簽的要求,提出了一種新的在ARM平臺下采用邊沿捕獲統計定時器數判斷數據的方法,并對FM0編碼進行解碼。與傳統的使用定時器定時采樣高低電平的FM0解碼方法相比,該解碼方法可以減少定時器定時誤差累積的影響;可以將捕獲定時器數中斷與數據判斷解碼相對分隔開,使得中斷對解碼影響很小,實現捕獲與解碼的同步。通過實驗表明,這種方法提高了解碼的效率,在160 Kb/s的接收速度下,讀取一張標簽的時間約為30次/s。
Abstract:
Aiming at the requirement of receiving correctly decoded data from the tag under high-speed communication which complied with EPC Gen2 standard in the design of UHF interrogator, the article introduced a new technology for FM0 decoding which counted the timer counter to judge data by using the edge interval of signal capture based on the ARM7 platform. Compared with the traditional FM0 decoding method which used the timer timed to sample the high and low level, the method could reduce the accumulation of timing error and could relatively separate capture timer interrupt and the data judgment for decoding, so that the disruption effect on the decoding was small and realizd synchronization of capture and decoding. Testing result shows that the method improves the efficiency of decoding, at 160 Kb/s receiving speed, the time of the interrogator to read a tag is about 30 times/s.