Orthogonal variable spreading factor channelization codes are widely used to provide variable data rates for supporting different bandwidth requirements in wideband code division multiple access (WCDMA) systems. A new...Orthogonal variable spreading factor channelization codes are widely used to provide variable data rates for supporting different bandwidth requirements in wideband code division multiple access (WCDMA) systems. A new code match scheme for WCDMA code tree management was proposed. The code match scheme is similar to the existing crowed-first scheme. When choosing a code for a user, the code match scheme only compares the one up layer of the allocated codes, unlike the crowed-first scheme which perhaps compares all up layers. So the operation of code match scheme is simple, and the average time delay is decreased by 5.1%. The simulation results also show that the code match strategy can decrease the average code blocking probability by 8.4%.展开更多
Intermediate spoofing can impact most off-the-shelf Global Navigation Satellite Systems （GNSS） receivers, therefore low cost detection of such spoofing is very important to protect the reliability of the GNSS receiv...Intermediate spoofing can impact most off-the-shelf Global Navigation Satellite Systems （GNSS） receivers, therefore low cost detection of such spoofing is very important to protect the reliability of the GNSS receivers used in critical safety and financial applications. This paper presents two strategies to analyze attacks by intermediate spoofing attackers to identify the weaknesses of such attacks. The analyses lead to a code and carrier phase consistency detection method with simulation results showing that this method can indicate the receiver when spoofing has occurred. The method can be used by most receivers, is inexpensive, and requires only a small software upgrade.展开更多
基金Project(60202005) supported by the National Natural Science Foundation of China
文摘Orthogonal variable spreading factor channelization codes are widely used to provide variable data rates for supporting different bandwidth requirements in wideband code division multiple access (WCDMA) systems. A new code match scheme for WCDMA code tree management was proposed. The code match scheme is similar to the existing crowed-first scheme. When choosing a code for a user, the code match scheme only compares the one up layer of the allocated codes, unlike the crowed-first scheme which perhaps compares all up layers. So the operation of code match scheme is simple, and the average time delay is decreased by 5.1%. The simulation results also show that the code match strategy can decrease the average code blocking probability by 8.4%.
基金National Natural Science Foundation of China(No.61101070)
文摘Intermediate spoofing can impact most off-the-shelf Global Navigation Satellite Systems （GNSS） receivers, therefore low cost detection of such spoofing is very important to protect the reliability of the GNSS receivers used in critical safety and financial applications. This paper presents two strategies to analyze attacks by intermediate spoofing attackers to identify the weaknesses of such attacks. The analyses lead to a code and carrier phase consistency detection method with simulation results showing that this method can indicate the receiver when spoofing has occurred. The method can be used by most receivers, is inexpensive, and requires only a small software upgrade.
