Relay-attack resistant communications
AssigneeTexas Instruments Incorporated
InventorsTOMAS MOTOS, KHANH TUAN LE
Life of this patent
Estimating the term…
Abstract
A method of relay-attack resistant communications in a wireless communications system that includes a master wireless device (Master) sending a synchronization signal to a slave wireless device (Slave). The synchronization signal includes timing information including a common time reference and a timeslot duration for interlocking Master communication timeslots for Master and Slave communication timeslots so that an alternating TX and RX role pattern is provided. The Master analyzes Slave packet data received from the Slave to identify overlaps of a transmission from the Master and the slave packet data, and in a case of detecting overlap, suspends communications from Master to Slave to prevent a relay-attack.
Claims18
A method of relay-attack resistant communications, comprising:
- a master wireless device (Master) sending a synchronization signal to a slave wireless device (Slave), wherein said synchronization signal comprises timing information including a common time reference and a timeslot duration for interlocking Master and Slave communication timeslots so that an alternating TX and RX role pattern for said Master and for said Slave is provided;
- said Master analyzing Slave packet data received from said Slave to identify an overlap of a transmission from said Master and said Slave packet data which results in a packet error, and
- in a case of said packet error, suspending communications from said Master to said Slave to prevent a relay-attack.
A radio system, comprising:
- Tx chain including an RF PLL coupled to a power amplifier (PA) by a first switch (S1);
- an Rx chain including an amplifier (LNA) and an RX mixer;
- a second switch (S2) switchably coupling an output of said RF PLL to said RX mixer;
- a digital radio including a processor having an associated memory including a stored communications protocol algorithm coupled to said RF PLL, to said RX mixer, and to said S2,
- said communications protocol algorithm for:
- based on a time reference and a timeslot duration, establishing interlocking communication timeslots with a second said radio system so that an alternating TX and RX role pattern for said radio system and said second radio system is provided;
- when said radio system is in said TX role causing a modulated RF signal from said digital radio to be an information-carrying packet data signal, said S1 to be closed, said S2 to be open so that said PA receives a RF PLL signal from said RF PLL, and
- when said radio system is in said RX role causing said modulated RF signal to be zero, so that said RF PLL only produces a carrier signal, said Si is open, and said S2 is closed so that said RX Mixer receives said RF PLL signal from said RF PLL.
Dependencies are inferred from the claim text.