Patent ID: 7940693
Filing Date: 2011-05-10
Classification: H04L,H04W

Abstract:
1. A wireless communication system, comprising: a first communication module, after transmitting a first pilot, sequentially transmitting N first packets each with a first delay time, and after receiving a second pilot, sequentially receiving N second packets each with a fourth delay time, each of the N first packets respectively corresponding to one of the N second packets, N being a natural number larger than 1, the first communication module spending a first processing time transmitting and receiving each packet; and a second communication module, after receiving the first pilot, sequentially receiving the N first packets each with a second delay time, and after transmitting the second pilot, sequentially transmitting the N second packets each with a third delay time, the second communication module spending a second processing time transmitting and receiving each packet; wherein, according to the N first processing times, the N second processing times, the N first delay times, the N second delay times, the N third delay times, and the N fourth delay times corresponding to the N first packets and the N second packets, the first communication module calculates N reference times and averages the N reference times to obtain a time of flight (TOF); wherein the first processing time comprises a first transmitting time, a first receiving time, and a first influence time; the first communication module spends the first transmitting time transmitting each packet, spends the first receiving time receiving each packet, and spends the first influence time on a wireless environment and a system load; the first processing time is shown as follows: A(Process)=T×A (Process)+R×A(Process)+Φ×A; wherein A(Process) represents the first processing time, T×A(Process) represents the first transmitting time, R×A(Process) represents the first receiving time, and Φ×A represents the first influence time; wherein the second processing time comprises a second transmitting time, a second receiving time, and a second influence time; the second communication module spends the second transmitting time transmitting each packet, spends the second receiving time receiving each packet, and spends the second influence time on the wireless environment and the system load; the second processing time is shown as follows: B(Process)=T×B(Process)+R×B(Process)+Φ×B; wherein B(Process) represents the second processing time, T×B(Process) represents the second transmitting time, R×B(Process) represents the second receiving time, and Φ×B represents the second influence time; wherein the N reference times are calculated according to the following N first equations: wherein T×A N represents a first time point when the first communication module transmits the Nth first packet, R×A N represents a second time point when the first communication module receives the Nth second packet, T N represents the Nth reference time, A (Process) N represents the first processing time corresponding to the Nth first packets, and B (Process) N represents the second processing time corresponding to the Nth second packets.