US-12627988-B2 - Communication device and method for monitoring a wireless communication exchange

US12627988B2US 12627988 B2US12627988 B2US 12627988B2US-12627988-B2

Abstract

A communication exchange between two wireless communication devices is monitored. A communication device configured to function as a Sniffer device synchronizes the communication device to a frequency and a timing employed between the two wireless communication devices on a main wireless communication channel. The wireless communication exchanges are monitored, in which the wireless communication exchanges are packet-based data exchanges or tone-based data exchanges. The operations for wireless communication exchanges are repeated across a plurality of different frequencies. The communication device then combines a plurality of phase and/or magnitude measurements and determines a value of phase and/or magnitude error introduced by each device based on the combined plurality of phase and/or magnitude measurements.

Inventors

Mihai-Ionut Stanciu
Zahir SMAIL
Khurram Waheed
John Edward Vandermeer

Assignees

NXP USA, INC.

Dates

Publication Date: 20260512
Application Date: 20230810
Priority Date: 20220907

Claims (15)

1 . A method of monitoring of a communication exchange between two wireless communication devices, the method comprising, at a communication device configured to function as a Sniffer device: synchronizing to a frequency and a timing employed between the two wireless communication devices on a main wireless communication channel; monitoring wireless communication exchanges between the two wireless communication devices on the main wireless communication channel, where the wireless communication exchanges are one of: packet-based communication exchanges or tone-based communication exchanges; repeating the monitoring on the main wireless communication channel of wireless communication exchanges between the two wireless communication devices across a plurality of different frequencies; combining a plurality of at least one of phase measurements or magnitude measurements from the respective two wireless communication devices; and determining a value of phase error introduced by each of the two wireless communication devices based on the combined plurality of the at least one of phase measurements or magnitude measurements.
2 . The method of monitoring of claim 1 , further comprising: receiving information from each of the two wireless communication devices via at least one side communication channel that is separate from the main communication channel, wherein the received information comprises at least one of: respective phase measurements of wireless communication exchanges between the two wireless communication devices, respective magnitude measurements of wireless communication exchanges between the two wireless communication devices, or respective time-stamp measurements of wireless communication exchanges between the two wireless communication devices, measured by the two wireless communication devices on the main wireless communication channel from the wireless communication exchanges; and repeating the monitoring on the main wireless communication channel and receiving information from each of the two wireless communication devices via the at least one side communication channel across the plurality of different frequencies.
3 . The method of monitoring of claim 2 wherein the at least one side communication channel is one of a wireline static communication channel or a wireless communication channel employing a communication protocol when the communication device configured to function as the Sniffer device has access to security keys of the communication protocol.
4 . The method of monitoring of claim 2 further comprising: combining first quadrature (IQ) values IQ IR k , IQ RI k , received via the at least one side communication channels and second quadrature (IQ) values IQ IS k , IQ RS k received over-the-air using equations: IQ R , c ⁢ o ⁢ m ⁢ b ⁢ i ⁢ n ⁢ e ⁢ d k = IQ IR k * conj ⁡ ( IQ IS k ) * IQ R ⁢ S k = e j ⁡ ( φ k R , TX - φ k R , RX ) * e j ⁡ ( Δ ⁢ Φ k - Δ ⁢ Φ k I ⁢ S + Δ ⁢ Φ k R ⁢ S ) IQ I , combined k = IQ RI k * conj ⁡ ( IQ RS k ) * IQ IS k = e j ⁡ ( φ k I , TX - φ k I , RX ) * e j ⁡ ( Δ ⁢ Φ k + ΔΦ k I ⁢ S - ΔΦ k R ⁢ S ) wherein a right-hand side of the equations provide a combination of a predictable linear of at least one of phase error, magnitude error, or a radio-specific error.
5 . The method of monitoring of claim 1 , wherein combining the plurality of the at least one of phase measurements or magnitude measurements from the respective two wireless communication devices comprises one of: multiplying IQ values in a quadrature (IQ) domain; or adding at least one of phase measurements or magnitude measurements in a phase domain when using tone-based communication exchanges.
6 . The method of monitoring of claim 1 wherein at least one of quadrature measurements, phase measurements, or magnitude measurements is performed in a phase domain using tone-based data exchanges, wherein combining the plurality of the at least one of phase measurements or magnitude measurements from the respective two wireless communication devices comprises adding a plurality of at least one of quadrature measurements, phase measurements, or magnitude measurements.
7 . The method of monitoring of claim 1 further comprising obtaining a distance measurement between the two wireless communication devices based on one of: time-stamps of received packet-based communication exchanges; or at least one of phase measurements or magnitude measurements of received tone-based communication exchanges.
8 . The method of monitoring of claim 7 wherein the distance measurement between the two wireless communication devices comprises one of: channel sounding information in a Bluetooth™ SIG wireless system; or a secure distance measurement in an 80 MHz ISM band.
9 . The method of monitoring of claim 1 wherein the method further comprises determining inconsistencies between transmit information and receive information, received from each of the respective two wireless communication devices using the at least one of phase measurements or magnitude measurements.
10 . The method of monitoring of claim 1 wherein the two wireless communication devices comprise: an Initiator radio device (I) with a normally distributed channel-k timing error ε I k , and a Reflector radio device (R) with a normally distributed channel k timing error ε R k .
11 . The method of monitoring of claim 10 , the method comprising at the communication device configured to function as the Sniffer device: receiving a radio transmission of a first data packet from the Initiator radio device (I) that includes a first departure time stamp T 1 k , that is also received at the Reflector radio device (R) that generates an arrival timestamp T 2 k in response thereto; receiving a radio re-transmission of the first data packet from the Reflector radio device (R) that includes a second departure timestamp T 3 k that is also received at the Initiator radio device (I) that generates an arrival timestamp T 4 k , in response thereto; capturing of over-the-air transmissions from the Initiator radio device (I) and the Reflector radio device (R) that includes quadrature (IQ) values and a generation of arrival timestamps T s , 1 k , T s , 2 k ; calculating a first delta time value Δ ⁢ T l k = T 4 k - T 1 k , calculating a second delta time value Δ ⁢ T R k = T 3 k - T 2 k , calculating a third delta time value Δ ⁢ T S k = T S , 2 k - T S , 1 k calculating a fourth delta time value Δ ⁢ T I k - Δ ⁢ T S k , calculating a fifth delta time value Δ ⁢ T R k - Δ ⁢ T S k , repeating the receiving, capturing and calculating operations across multiple channels; and calculating statistical mean values of differences between the first delta time value and third delta time value ( Δ ⁢ T l k - ΔT S k ) and between the second delta time value and third delta time value ( Δ ⁢ T R k - Δ ⁢ T S k ) , wherein the calculated statistical mean values across multiple channels converge to a channel timing error of the Initiator radio (I) ε I k and a channel timing error of the Reflector radio (R) ε R k .
12 . The method of monitoring of claim 1 further comprising the communication device configured to function as the Sniffer device having a priori knowledge of at least one parameter in the communication exchange on the main communication channel selected from a group consisting of modulation used, frequency hopping timing used, frequency hopping pattern used, whether a packet or a tone is to be received, a duration of tone signals, a data-rate and number of modulated bits for data packets, wherein the method further comprises; synchronizing with the communication exchange by the communication device using the at least one parameter after first receiving a packet or a tone on the main communication channel.
13 . A communication device configured to operate as a wireless Sniffer device and monitor a wireless communication exchange between two wireless communication devices, the communication device comprising: a frequency generation and timing circuit configured to synchronize the communication device to a frequency and a timing employed between the two wireless communication devices on a main wireless communication channel; a receiver circuit coupled to the frequency generation and timing circuit and configured to receive the wireless communication exchanges between the two wireless communication devices on the main wireless communication channel, wherein the wireless communication exchanges comprise one of packet-based communication exchanges or tone-based communication exchanges; a signal processor coupled to the receiver circuit and configured to: process the received wireless communication exchanges; combine a plurality of at least one of phase measurements or magnitude measurements from the respective two wireless communication devices, following repeated operations of the monitored main wireless communication channel across a plurality of different frequencies; and determine, based on the combined plurality of at least one of phase measurements or magnitude measurements, a value of at least one of phase error or magnitude error, introduced by each of the two wireless communication devices.
14 . The communication device of claim 13 , further comprising: an interface, operably coupled to the signal processor and configured to receive information from each of the two wireless communication devices via at least one side communication channel that is separate from the main communication channel, wherein the information comprises at least one of respective phase measurements, respective magnitude measurements, or time-stamp measurements measured by the two wireless communication devices on the main wireless communication channel from the wireless communication exchanges, wherein the signal processor is configured to combine a plurality of the at least one of respective phase measurements, respective magnitude measurements, or time-stamp measurements from the respective two wireless communication devices, following repeated operations of the monitored main wireless communication channel and received information from each of the two wireless communication devices via the at least one side communication channel across the plurality of different frequencies.
15 . The communication device of claim 13 , wherein combining the plurality of the at least one of respective phase measurements or respective magnitude measurements from the respective two wireless communication devices comprises one of: multiplying quadrature (IQ) value measurements in a quadrature (IQ) domain following packet data communication exchanges; adding at least one of respective phase measurements or respective magnitude measurements in a phase domain following tone-based communication exchanges.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the priority under 35 U.S.C. § 119 of Romania application no. A202200546, filed on 7 Sep. 2022, the contents of which are incorporated by reference herein. FIELD OF THE INVENTION The field of the invention relates to a radio communication unit, and a method for monitoring a wireless communication exchange. The field of the invention is applicable to, but not limited to, monitoring of a wireless communication exchange between two wireless communication devices and determining a distance between these respective wireless communication devices. BACKGROUND OF THE INVENTION The use of radio communication systems is increasing rapidly, in areas such as the ‘Internet of Things (IoT™)’, which includes home automation, a variety of peer-to-peer communication applications, such as Apple™'s “Airdrop™”, or personal-exercise systems with a variety of physiological monitoring devices and many others. Many of these applications use the Bluetooth™ radio standard, which has become very well established, widely supported and developed. Localization testing is a known approach to check the content, user interfaces, functionality, and usability of software as it appears in multiple locations in a communication system. In such communication systems where radio communication devices appear in multiple locations, it is sometimes important to determine a distance between respective radio devices, so that the system can ensure that communications between certain devices can be achieved in a reliable manner. In narrowband localization systems, two or more devices are involved in determining such distance estimation. FIG. 1 illustrates a known signalling approach 100 that provides distance estimation in a localization system. In distance estimation, there is first a synchronisation step 110, followed by multiple tone exchanges between two radio devices, 120, 122 (with only two exchanges shown for simplicity purposes only. In the synchronisation step 110, a first radio device transmits a synchronisation (‘synch’) pattern 130 that is received by a second radio device, which then processes the received synch pattern 130 and re-transmits 132 it to the first radio device. In this manner, the second radio device (sometimes referred to as a ‘Reflector device’) aligns its timing to the first radio device (sometimes referred to as an ‘Initiator device’) and the Initiator device aligns its local oscillator (LO) frequency to that of the Reflector device. This is performed to align (in time) the crystal (local) oscillators of the Initiator device and the Reflector device, which are not a priori aligned in time prior to the wireless exchange (and noting that the two devices may have different crystal precisions and could drift in opposite direction thereby causing timing and frequency misalignments). Thus, the synchronisation step is used to estimate any such timing misalignment and compensate for it. On a certain radio frequency (RF) channel, a first device is transmitting an unmodulated carrier frequency, whilst the second device is receiving the unmodulated carrier frequency. Thereafter, the second device is transmitting the unmodulated carrier frequency, whilst the first device is receiving the unmodulated carrier frequency. Whilst receiving, each device performs a phase measurement in order to identify a phase change of the transmitted signal. Then, both Initiator device and Reflector device are hopping synchronously onto the next communication channel and they then perform the same process. Thus, in this manner, each two-way exchange occurs on a different RF channel, so that all the available frequencies are mapped, at least once, during one distance measurement exchange. The exchange of signals on different radio frequencies needs to be time synchronized, i.e., the RF frequency hopping needs to happen synchronously. Channel sounding information is then exchanged on the subsequent operations, using two-way exchanges 134 and 136, 138 and 140, etc. of tones (or data packets) between the Initiator device and the Reflector device. After hopping through all RF channels, each of the Initiator device and the Reflector device has performed its own set of phase measurements. However, each device is also introducing phase errors of its own due to RF impairments in its circuitry (mainly due to phase noise and local oscillator phase inconsistency when switching between transmit (TX) and receive (RX) operational modes). It is also known that it is often useful to be able to analyse a radio communications channel for the purposes of trouble-shooting or performance monitoring of communications between devices, and communication units. Signal analysers have been developed and used for this purpose. A signal analyser used in a research and development environment may be connected to the device(s) under test (DUT), e.g., two radio communication units coupled together by wired connections, which