Patent Description:
The invention is related to devices in the military area or aviation area or other technical areas where it is highly essential that the devices are very robust with a long lifetime and a high technical stability. If such a first device needs to be connected with such a second device, connectors and cables have to be used that follow the relevant standards for military or aviation. Such standards define e.g. robust plated electrical contacts and a solid housing which might have to be water-tight or other conditions need to be met. Furthermore, some of these connectors have up to several hundred pins in huge dimensions with several hundred parallel information lines. These high-end boundary conditions makes such connectors technical complicated and expensive.

<FIG> shows an example of a socket and a plug of such a connector. The socket is connected to or part of the first device and realizes a transmitter device with a transmitter interface to which more than <NUM> parallel information lines or cables of the device are connected. The plug realizes a receiver device with a receiver interface to which the same number of more than <NUM> parallel information lines or cables with the same configuration of the second device are connected. It was a long felt need to find a robust and mechanical simple solution to connect such devices.

<NPL> discloses a system of a transmitter and a receiver device that exchange data via an RFID wireless interface as serial data stream.

The invention is defined in the independent claim. The dependent claims define additional embodiments. The receiver device provides the received information at a receiver interface that has the same number and configuration of parallel information lines. In this way analog signals and/or digital data may be transmitted over the wireless interface. In a practical realization the plug of the first device shown in <FIG> may be replace by with a transmitter device with its information lines soldered within the first device that needs to be connected to the second device. The receiver device replaces the socket shown in <FIG>, with the information lines of the receiver device soldered within the second device. Either the transmitter device or the receiver device or both could have some short cable with the antenna of the RFID wireless interface at its end. This provides a simple and mechanical very robust connection of the first device to the second device that need to be connected with each other.

<FIG> shows a first embodiment of a system <NUM> of a transmitter device <NUM> and a receiver device <NUM> which realize a connection to exchange information between a first device <NUM> and a second device <NUM>. The first device <NUM> could be a computer of an airplane and the second device <NUM> could be a sensor array of <NUM> pressure sensors on one of the wing of the airplane to measure the pressure on different areas of the wing to detect turbulences. The connection between the computer and the sensor array has to be very robust with a long lifetime and a high technical stability. Information exchanged between the first device <NUM> and the second device <NUM> include analog signals on <NUM> parallel information lines or wires from the sensors and digital data on <NUM> parallel information lines or wires to a pre-processor of the sensor array. In a state of the art realizations a cable with these <NUM> parallel wires with two plugs needs to be connected with a socket of the first device <NUM> and a socket of the second device <NUM>. These sockets and the cable are replaced by the system <NUM> with its transmitter device <NUM> and its receiver device <NUM>.

The transmitter device <NUM> is soldered to the cables of above stated information lines of device <NUM> and replaces the socket of a state of the art realization. These cables with <NUM> parallel information lines provide the <NUM> analog signals and digital data in <NUM> parallel information lines of the first device <NUM> to a transmitter interface <NUM> of the transmitter device <NUM>. The receiver device <NUM> of the system <NUM> comprises a receiver interface <NUM> to provide the received <NUM> analog signals and the received <NUM> digital data streams to the second device <NUM>, which receiver interface <NUM> comprises the same number of parallel information lines as the transmitter interface <NUM>. This ensures that state of the art systems may implement the inventive system <NUM>, by unsoldering the sockets and soldering the transmitter device <NUM> to the cables of the first device <NUM> an by soldering the receiver device <NUM> to the cables of the second device <NUM>.

The transmitter device <NUM> comprises a transmitter protocol unit <NUM> to process the analog signals and the digital data on the <NUM> information lines of the transmitter interface <NUM> to generate a serial data stream <NUM>, that comprises all information needed to reconstruct the analog signal and the digital data in a receiver protocol unit <NUM> of the receiver device <NUM>. The transmitter device <NUM> furthermore comprises an RFID wireless interface <NUM> with an antenna to transmit the serial data stream <NUM> via an electromagnetic field to a close-coupled antenna of a RFID wireless interface <NUM> of the receiver device <NUM>. The electromagnetic field is generated by the transmitter of the RFID wireless interface <NUM> of the transmitter device <NUM> and received by the RFID wireless interface <NUM> of the receiver device <NUM> and has a frequency of <NUM>. Communication on this RFID wireless interface complies to ISO18. <NUM>, the so called NFC Standard. Other frequencies in the RFID area like <NUM> or <NUM> or a frequency in the area of <NUM> to <NUM> that comply to other standards could be used as well.

As the first device <NUM>, the computer of the airplane, is powered by the airplane, and the second device <NUM>, the sensor array, is a passive device, the second device <NUM> has to be powered by the first device <NUM>. Transmitter device <NUM> therefore is powered with 24V DC by electrical power provided at two power lines of the transmitter interface <NUM> and the receiver device <NUM> needs to provide the power received from the transmitter device <NUM> at two power lines of the receiver interface <NUM> to power the second device <NUM>. To enable that, the receiver device <NUM> comprises a power recovery unit <NUM> as part of the receiver in the RFID wireless interface <NUM> to recover the power needed to drive the power lines and information lines of the receiver interface <NUM> from the electromagnetic field. Such a power recovery unit <NUM> is known to a person skilled in the art like e.g. described in the Wireless Charging (WLC) Technical Specification Version <NUM> of the NFC Forum.

The transmitter device <NUM> furthermore comprises a voltage sensing unit <NUM> to sense the voltage level of <NUM> V DC at the power lines of the transmitter interface <NUM>. A micro controller unit <NUM> of the transmitter device <NUM> is built to include a voltage level information about the sensed voltage level into the serial data stream <NUM> received at a micro controller unit <NUM> of the receiver device <NUM>. The micro controller unit <NUM> communicates with the micro controller <NUM> based on a fixed protocol which identifies which data package comprises which information, what enables the micro controller unit <NUM> to receive the voltage level information and to provide it to a buck buster converter <NUM> of the receiver device <NUM> to generate the voltage level of 24V DC of the power lines at the receiver interface <NUM> with the same voltage level of <NUM> V DC as at the power lines of the transmitter interface <NUM>. This provides the advantage, that the system <NUM> can be used universal for devices powered with different voltage levels and it is ensured that the passive device is powered with the correct voltage level what avoids damages at the second device <NUM>.

The transmitter protocol unit <NUM> comprises analogue level shifter <NUM> for information lines that transmit an analog signal and a digital level shifter <NUM> for information lines that transmit digital data to shift the voltage level on the information lines of the transmitter interface <NUM> to a voltage level that may be processed by micro controller unit <NUM>. Analog signals may for instance be provided by the first device <NUM> at transmitter interface <NUM> within a range of +/- <NUM> V DC while the micro controller unit <NUM> may only process digital data in the range of +/- <NUM> V DC. The same might be the case with digital data provided by the first device <NUM> at the transmitter interface <NUM>. This provides the advantage, that the system <NUM> can be used universal for devices powered with different voltage levels and it is ensured that transmitter device <NUM> and receiver device <NUM> will not be damaged.

Transmitter protocol unit <NUM> furthermore comprises an analog multiplexer <NUM> connected to the analogue level shifter <NUM> for information lines that transmit an analog signal to provide the information from the analog signals to micro controller unit <NUM>. Transmitter protocol unit <NUM> furthermore comprises a digital multiplexer <NUM> connected to the digital level shifter <NUM> for information lines that transmit digital data to provide the information from the digital data to micro controller unit <NUM>. Micro controller unit <NUM> is built to compile the information received from the analog multiplexer <NUM> and the digital multiplexer <NUM> and the voltage sensing unit <NUM> into the serial data stream <NUM> based on the protocol with the micro controller unit <NUM>.

Receiver protocol unit <NUM> furthermore comprises an analog demultiplexer <NUM> connected to the micro controller unit <NUM> of the receiver device <NUM> to demultiplex the serial data stream <NUM> received by the RFID wireless interface <NUM> of the receiver device <NUM> to provide the received analog signals on parallel lines. The receiver protocol unit <NUM> furthermore comprises a digital demultiplexer <NUM> connected to the micro controller unit <NUM> of the receiver device <NUM> to demultiplex the serial data stream <NUM> received by the RFID wireless interface <NUM> of the receiver device <NUM> to provide the digital data on parallel lines.

Receiver protocol unit <NUM> furthermore comprises an analog level shifter <NUM> connected to the analogue demultiplexer <NUM> to provide the analog signal at the parallel information lines of the receiver interface <NUM> with the same voltage level the analog signal was provided at the transmitter interface <NUM>. The receiver protocol unit <NUM> furthermore comprises a digital level shifter <NUM> connected to the digital demultiplexer <NUM> to provide the digital data at the information lines of the receiver interface <NUM> with the same voltage level the digital data were provided at the transmitter interface <NUM>.

This symmetrical realization of the transmitter protocol unit <NUM> and the receiver protocol unit <NUM> ensures that all analog signals and digital data of the transmitter interface <NUM> will be provided at the receiver interface <NUM>.

<FIG> shows a first part of a time diagram <NUM> of signals and information on information lines of the system <NUM> shown in <FIG>. At a time instance t1 power of the first device <NUM> is switched on and power lines (TX power lines) at the power lines of transmitter device <NUM> are powered with <NUM> V DC and system voltage (TX System Voltage) of <NUM> V DC is generated and supplied to all units of transmitter device <NUM>. After a start-up routine (TX start-up) and initialization routine (Initialize TX) within transmitter device <NUM> voltage sensing unit <NUM> of transmitter device <NUM> starts to sense (Read TX voltage) the voltage level on the power lines of transmitter interface <NUM> at time instance t2. Afterwards the RFID wireless interface <NUM> of transmitter device <NUM> starts to transmit the electromagnetic field (RF ON) and power recovery unit <NUM> starts to generate the RX system voltage of <NUM> V DC to supply all units of the receiver. After that the RF communication with the RFID wireless interface <NUM> of the receiver device <NUM> starts based on the NFC standard protocol, which is driven by information and data exchange between micro controller unit <NUM> (TX MCU) and micro controller unit <NUM> (RX MCU). During an initial data exchange the voltage level information is received at receiver device <NUM> and at time instance t3 power lines (RX power lines) of receiver interface <NUM> are powered by buck boost converter <NUM>.

During time instances t3 and t4 transmitter protocol unit <NUM> generates the serial data stream <NUM> that is transmitted by the RFID wireless interface <NUM> and received by the RFID wireless interface <NUM> during time instances t4 and t5. This process of the generation of the serial data stream <NUM> based on analog signals and digital data receive at transmitter data interface <NUM> and transmission of the serial data stream <NUM> to receiver protocol unit <NUM> to reconstruct these analog signals and digital data on receiver data interface <NUM> continues and repeats during the following time instances t6 and t7 and t8 and so on. This enables to provide the analog signals and digital data of the first device <NUM> to second device <NUM> with only a short delay caused by processing times of transmitter device <NUM> and receiver device <NUM>.

The major advantages achieved with replacement of plugs and sockets and the cable of the start of the art is that no mechanical wear happens as the antenna of RFID wireless interfaces <NUM> and <NUM> have to be located only close-by. Furthermore the huge number of different types of plugs and sockets for all kind of different devices may be omitted what reduces spare parts to be held in stock. As the soldered electrical connection of the parallel information lines between the first device <NUM> and transmitter device <NUM> and the second device <NUM> and receiver device <NUM> is much more reliable than a plug connection, the use of system <NUM> increases the reliability. Furthermore the housing of the devices may be sealed against dust or water what makes the devices much more robust.

In a further embodiment of the invention transmitter device <NUM> may be integrated into the first device <NUM> and receiver device <NUM> may be integrated into the second device <NUM>. The first device <NUM> and the second device <NUM> only have cable with antennas at their end which need to be put in close contact of a few centimeters to enable the transmission of analog signals and digital data as explained above. The length of the cables may be adapted depending of the application the devices are used for.

In a further embodiment of the invention data compression and decompression may be used to reduce the amount of data of the serial data stream transmitted.

The antennas used in the RFID wireless interfaces can be realized in many forms, most interesting will be the use of lumped elements (ordinary SMD inductors) as they can be reliable produced. Also, a combination of a spiral transmitter coil and a lumped receiver element coil that sits inside the second device (or the other way around) may be used.

Claim 1:
System (<NUM>) including a transmitter device (<NUM>), for the transmission of an analog signal and/or digital data provided to the system (<NUM>) at a transmitter interface (<NUM>) of the transmitter device (<NUM>), which transmitter interface (<NUM>) comprises at least two parallel information lines, and
a receiver device (<NUM>) of the system (<NUM>) with a receiver interface (<NUM>) adapted to provide the received analog signal and/or digital data by the system (<NUM>), which receiver interface (<NUM>) comprises the same number of parallel information lines as the transmitter interface (<NUM>), characterized in,
that the transmitter device (<NUM>) comprises a transmitter protocol unit (<NUM>) adapted to process the analog signal and/or digital data on the information lines of the transmitter interface (<NUM>) and adapted to generate a serial data stream (<NUM>) that comprises information to reconstruct the analog signal and/or digital data and,
that the transmitter device (<NUM>) comprises an RFID wireless interface (<NUM>) with an antenna adapted to transmit the serial data stream (<NUM>) via an electromagnetic field to a close-coupled
antenna of a RFID wireless interface (<NUM>) of the receiver device (<NUM>) close-by the antenna of the transmitter device (<NUM>) and,
that the receiver device (<NUM>) comprises a receiver protocol unit (<NUM>) adapted to process the received serial data stream (<NUM>) to reconstruct the analogue signal and/or digital data and adapted to provide it on the information lines of the receiver interface (<NUM>) with the same configuration as provided at the information lines of the transmitter interface (<NUM>), which transmitter device (<NUM>) is powered by electrical power provided at two power lines of the transmitter interface (<NUM>) and which receiver device (<NUM>) is adapted to provide power received from the transmitter device (<NUM>) at two power lines of the receiver interface (<NUM>) and, that the receiver device (<NUM>) comprises a power recovery unit (<NUM>) adapted to recover the power needed to drive the power lines and information lines of the receiver interface (<NUM>) from the electromagnetic field.