PT106920A - REMOTE CONTROL SYSTEM WITHOUT BATTERIES - Google Patents

Abstract

REMOTE CONTROL SYSTEM WITHOUT NEED OF ENERGY SOURCE, BASED ON PASSIVE RFID TECHNOLOGY, UNDERSTANDING A DRIVER OR CONTROLLING DEVICE THAT DOES NOT REQUIRE USE OF OWN ENERGY SOURCES, BATTERIES OR BATTERIES, AND DEVICE TO CONTROL (EX TV) INCORPORATING A RFID READING SYSTEM, IN PARTICULAR EMBEDDED IN THE DEVICE TO BE CONTROLLED OR ALTERNATIVELY, TO ENSURE COMPATIBILITY WITH INFRARED (IV) EQUIPMENT, MOUNTED EXTERNALLY USING AN RFID-IV INTERFACE. THE REMOTE CONTROL INTEGRATES AN ANTENNA, A PLURALITY OF N KEYS AND NON-PASSIVE RFID CHIPS (WITHOUT BATTERIES) AND A MULTI-PORT NETWORK 1: N. EACH REMOTE CONTROL KEY IS ASSOCIATED WITH A CHIP RFID (AND THE RESPECTIVE ID) ALLOWING UNIQUE TO IDENTIFY THE PRESSED KEY BY THE USER. THE MULTI-PORT NETWORK 1: N ALLOWS THE ANTENNA TO BE SHARED BY THE VARIOUS CHIPS, SO THE CHIP ASSOCIATED WITH THE PREMIUM KEY IS READ ON EACH INSTANT WHILE THE REMAINERS REMAIN SILENTLY.

Description

DESCRIPTION " REMOTE CONTROL SYSTEM WITHOUT BATTERIES "

SUMMARY OF THE INVENTION The present invention relates to a remote control system which does not require the use of batteries or batteries. To this end, passive radio frequency identification (RFID) chips are used, in which both data transfer and power transmission are made using radio signals. When compared to traditional systems (infrared and battery operated), this battery-free control has many advantages: the main advantage is that there are no batteries or batteries. If on the one hand this translates into greater convenience and savings for the user who no longer needs to maintain the command, on the other hand, the absence of batteries represents an added value for the environment. Radio frequency communication through passive RFID devices typically includes a identifier chip connected to a radio frequency antenna, wherein the antenna allows communication of data to / from the identifier chip and allows feeding of the identifier chip via magnetic inductive coupling ( short distance), inductive magnetic resonant coupling (average distances), or electromagnetic coupling (long distances), in particular being the emitted radio frequency modulated for data communication.

Batteries generate toxic waste at the end of their useful life which, if not collected and treated, poses risks to the environment and public health. The task of collection and treatment is further hampered by the small size of these portable batteries 1 and the fact that they are not exactly known at the end of life.

As far as communication is concerned, the use of radio technology enables a greater range of coverage and enables communication without a line of sight, that is to say even in the presence of obstacles between the remote control and the device to be controlled.

In the present invention, the remote control does not require the use of batteries or batteries and the device to be controlled (eg TV or Cable Box) incorporates an RFID remote reading system of the remote control. Such a reading system may be embedded from the root into the device to be controlled (at the time of manufacture) or alternatively may be mounted externally. In the second case, and as an integral part of the invention, a system of adaptation and interface between the now proposed system and conventional infrared (IV) technology is proposed in order to ensure compatibility with traditional systems.

A device for remote control by RFID communication is described which comprises: a RFID communication antenna with impedance Zo; an RFID communication element for user control which comprises: - an RFID communication chip with its own impedance or adapted equal to ZO; and a contact switch normally closed in parallel with said RFID communication chip, referred to as a controllable parallel RFID communication element, or a contact switch normally open in series with said RFID communication chip, referred to as controllable communication element RFID series; Said contact switch being connected to a compensation impedance so that at the operating frequency of said device the closed contact switch operates as a short circuit; and said RFID communication chip is connected directly or indirectly to said RFID communication antenna.

A preferred embodiment comprises: - a plurality of N said serial, or parallel, serial or parallel controllable RFID communication elements; a 1: N multi-port network, said antenna interconnecting the plurality of N controllable RFID communication elements, comprising, for said interconnection, transmission lines with predefined phase rotation; in which the controllable elements of parallel RFID communication, if any, are interconnected each with the RFID communication antenna by a 90 ° phase rotation optionally added with a positive or negative multiple of 180 °; and wherein controllable RFID serial communication elements, if any, are interconnected each with the RFID communication antenna by a positive or negative 0 ° or multiple 180 ° phase rotation.

A preferred embodiment comprises only controllable parallel elements of RFID communication interconnected in star in the RFID communication antenna.

A preferred embodiment comprises only controllable serial RFID communication elements cascaded to the RFID communication antenna.

A preferred embodiment comprises only controllable controllable RFID communication elements interconnected in a cascade of two or more stars to the RFID communication antenna.

A more preferred embodiment comprises controllable serial RFID communication elements interconnected in each of said cascades.

In a preferred embodiment, said compensating impedance is an LC loop, wherein the inductance L includes the contact switch inductance.

In a preferred embodiment, the inductance L is the contact switch inductance.

In a preferred embodiment, the switch is a contact switch.

In a preferred embodiment, the switch comprises a contact sliding piece, a contact tip piece, a contact rotating part, a contact pivot piece, or a contact lifting piece.

In a preferred embodiment, the 1: N multi-port network comprises microwave transmission lines and / or co-planar waveguides.

There is further described a system for remote control by RFID communication of an apparatus comprising one or more of the devices for remote control by RFID communication as described above; and an RFID communication reader for reading chips from said RFID communication remote control devices.

In a preferred embodiment, said RFID communication reader is contained in said apparatus to be controlled remotely.

A preferred embodiment further comprises an RFID-IV interface connected to said RFID communication reader and connected by infrared to the apparatus to be controlled remotely. Prior Art

Traditionally, remote control systems use infrared (IR) signals and the remote control is powered by batteries. This technology has some limitations, namely the need for line of sight in communication and the use of disposable / portable batteries. The need for batteries not only represents a monetary cost associated with maintenance, but also an environmental cost associated with the toxic waste generated by the end-of-life batteries.

Considering the case of Portugal, if we take as a base the number of usual residences in 2011, 4 million (INE data for Sensos 2011), and assume that 75% of these residences have 1 TV, 40% have a box of cable TV and 30% have sound equipment, we reach an average of 5.8 million remote controls in Portugal. Considering two batteries per remote control and two annual exchanges we have reached an average of 23.2 million batteries spent annually only on remote controls for typical entertainment devices. This number is associated not only with the cost of purchasing batteries as well as the cost of treatment of toxic waste from end-of-life batteries. The present invention proposes an ecological system of non-stationary remote controls based on passive RFID technology. From the user's point of view, such a solution brings greater convenience and benefits as it eliminates the need and cost associated with battery replacement. On the other hand, unlike conventional (infrared) technology, the use of radio signals enables communication without a line of sight and greater communication distances. 5

Also for the purpose of disposing of batteries, alternative solutions have been proposed using other forms of " clean energies ". These solutions include for example remote controls that take advantage of the mechanical energy generated by the user himself when he presses a key (using piezoelectric sensors to generate electric energy) or remote controls that use dynamos systems to convert the mechanical energy generated by the user into electrical energy . In dynamo-based solutions the high weight and size are disadvantages to consider. Solutions based on piezoelectric sensors are limited by the reduced amount of energy that can be obtained with this technology, which may limit the autonomy and range of communication of the system.

In the present invention it is preferred to have a dedicated radio energy transmission system (which in this case is the radio signal generator of the RFID reader). However, here it becomes necessary to implement an efficient mechanism of transmitted energy management. Part of the solution may involve the use of an ON-OFF control of the radiated signal. On average, this mechanism greatly reduces the reader's consumption. In addition, a user presence detection subsystem can be introduced in the vicinity of the device to be controlled (eg TV) that activates the RFID reader only when necessary (currently some televisions already have built-in motion sensors). RFID (Radio Frequency Identification) systems are already well known. An RFID system is typically composed of a mobile device called a label and a fixed device called a reader. In the case of passive RFID systems, the label has no batteries or batteries. In this case the energy required for its operation is sent by the RFID reader via radio signals. In addition to the antenna and the radio system for communication with the reader, the label includes a memory for storing data (eg identification number - ID, or user data). The RFID reader also has an antenna and a radio system whose function is to remotely access / read the data stored in the memory of the chip. However, RFID chips were originally designed to function independently and independently and their application is typically limited to identifying people, animals and objects. On the other hand, due to energy limitations, passive RFID chips are not equipped with any control or sensing functionality. Typical commercial chips also lack digital interfaces for communication with the outside. With respect to the use of RFID in remote control systems, patent documents US 6531964B1 and US2008 / 0094181A1 are pointed out that although they have in common with the present invention the use of RFID technology and respective concepts, are not endowed with the same features and advantages of the present invention (as will be explained later). US6531964B1 proposes a remote control system based on RFID chips in the Low Frequency (LF) band - low frequency (62.5 kHz and 125 kHz). In this frequency band (LF) the interconnection between the RFID chips, the switches / keys and the antenna is trivial, requiring only a conductive element (copper track or wire) and not needing any special circuit drawing technique (as is in the case of the UHF band). However, the system proposed in US6531964B1 (LF) has a very limited reading range due to the type of coupling used (inductive). Thus the main advantage of the present invention compared to that proposed in the patent discussed above relates to the greater reading distance. On the other hand the circuits / antennas have reduced dimensions due to the use of a much smaller electrical length (greater frequency).

It should be noted that the techniques applied in the patent US6531964B1 do not directly or obviously allow to evolve into a UHF solution. While in the first case the interconnection of the various RFID chips is trivial, since in the case of the UHF band, preferable for its advantages over the LF band, such interconnection is not direct. Proof of this is the solution presented in US2008 / 0094181A1, in which a system of extremely high complexity is proposed to interconnect the various RFID chips. However, the latter proposition fails precisely because of its high complexity, which not only compromises the cost of the final product but is also an inconvenience to the very manufacturing process of the remote control. Briefly, US2008 / 0094181A1 proposes a remote control based on UHF RFID modules (each module incorporates an RFID chip and an antenna), wherein the interconnection between the various RFID modules, the switches / keys and the various antennas is performed by resonant coupling inductive through a multilayer structure (hence the high complexity of the system). In the system proposed in this document there are a total of 7 layers including the support of the N RFID modules (and their N antennas, where N is the number of keys of the command), the layer of the N keys, the layer of the main antenna, a layer with N secondary antennas which, resonated through the N keys, establish a bridge (by inductive coupling) between the desired RFID module (associated with the key pressed) and the main antenna. In addition there are layers of insulation and a layer of N auxiliary antennas that serve to reinforce the coupling between the antennas of the RFID modules and the secondary antennas. In this implementation a total of 7 layers and 3N + 1 antennas are required (N antennas of N modules, N secondary antennas, N auxiliary antennas and 1 main antenna), which shows the very high complexity of the solution.

In contrast, the present invention proposes an extremely low complexity interconnection system. This feature enables a very low production / assembly cost and cost of the final product.

The remote control (remote control) without proposed batteries integrates an antenna, a plurality of N keys, associated with N passive RFID chips, and a multi-port 1: N network. The multi-port network, RFID chips and keys are arranged in such a way that at any time only the RFID chip associated with the user-pressed key is connected to the antenna of the remote control (readable by an RFID reader), while the remaining remain silent. This will allow the device to be controlled (via an RFID reader) to uniquely identify the key pressed by the user. The device to be controlled (eg TV or other) incorporates an RFID reader that reads the RFID chip associated with the key pressed by the user in order to identify it. Alternatively, in order to ensure compatibility with conventional (infrared) systems already installed, an RFID-Infrared interface is also proposed as an integral part of this invention.

Among the advantages of the proposed system are the need for batteries and the possibility of communication without line of sight and long distances. A very low cost system is presented using commercially available and very low cost RFID technologies (such as the EPC Global Gen2 Classl). In particular, the cost is especially reduced when the chips are merely identifier chips, that is, very simple chips that only provide a unique identification to each chip, e.g. numerical or alphanumeric.

Other advantages are that it is possible to integrate chips from different manufacturers and / or different generations into the same device, which are thus activated at the user's choice, independently and without any risk or need for interaction between them. The interconnection of the various RFID chips is performed by a multi-port network, in particular single layer planar. The proposed 1: N ports arrangement is capable of doing the multiplexing of a single antenna to N RFID chips. Although the examples illustrated in this document consider printed transmission lines, the 1: N network may be implemented in any suitable transmission line technology such as co-planar or other waveguides. It is also to be noted that although RFID chips operating in the UHF band (860MHz - 960MHz) are considered by way of example, the present embodiments are equally valid for RFID chips operating in other suitable frequency bands (2.4-2.5 GHz, 5.9GHz, etc.).

DESCRIPTION OF THE FIGURES For illustrative purposes only and without limitation, the accompanying drawings show:

Figure 1 (a): Parallel activation / deactivation mechanism of the RFID chip.

Figure 1 (b): RFID chip serial activation / deactivation mechanism.

Figure 2 (a): Parallel and serial activation / deactivation mechanisms integrated with an antenna, forming a single-key remote control.

Figure 2 (b): Remote control with two keys using the parallel activation / deactivation mechanism.

Figure 2 (c): Remote control with two keys using the serial on / off mechanism.

Figure 2 (d): Remote control with N keys using star configuration and parallel activation / deactivation mechanism. Figure 2 (e): Remote control with N keys using cascade configuration and serial activation / deactivation mechanism. Figure 2 (f): Remote control with N keys using tree configuration and parallel activation / deactivation mechanism. Figure 2 (g): Remote control with N keys using hybrid configuration (cascade + tree) and serial and parallel activation / deactivation mechanisms.

Figure 3 (a): Remote control system incorporated into the device to be controlled.

Figure 3 (b): Remote control system with external RFID-Infrared interface.

Detailed description of the invention

The embodiments described herein relate to a remote control system, in particular without batteries, in which the remote control does not require the use of batteries or batteries. This is done using chips, said radio frequency identifiers (RFID), passive chips to implement the remote. For the following description and without limiting any limitation, the UHF frequency band, commercial RFID chips compatible with IS018000-6C standard, lossless transmission lines, characteristic impedance of the Z0 system, adapted impedance of the RFID chip and antenna impedance also Z0, commercial contact switches.

First, a mechanism is required to enable the user to enable and disable RFID chips. Figure 1 refers to two proposed mechanisms of activation / deactivation: parallel mechanism and serial mechanism. In the parallel mechanism (Figure 1a) a normally closed contact switch (5) is placed in parallel with the RFID chip (3) adapted to Z0. By default the switch is closed, short-circuiting the terminals of the chip and putting it in an inactive mode, making it impossible to read by an RFID reader. Once the user presses the desired switch / switch, the respective switch is left open, allowing the chip to be readable by an RFID reader. The matching mesh (4) adjusts the input impedance of the RFID chip to the characteristic impedance of the system, Z0. Since the switch does not exactly have a short circuit at the desired frequency, an LC circuit consisting of a coil (8) and a capacitor (7) are in series with the switch so as to adjust its resonance frequency and achieve a short-circuit to the operating frequency. The inductance of the coil (8) may be the inductance of the switch itself in closed mode. It is assumed that the impedance of the open-mode switch is quite high and can be approximated to an open circuit. Thus, in the following descriptions, the circuit with parallel activation / deactivation (Figure 1a) will now be represented by an equivalent impedance (1), whose value ZP theoretically varies between two values: 0Ω for the case where the switch is closed by default) and Z0 for the case where the user presses the key, opening the switch.

In the series on / off mechanism (Figure 1b), a normally open switch (6) is in series with the chip adapted to Z0. In this case, with the default switch open, the RFID chip will be off by default, switching to active mode when the user presses the key and closes the switch (6). In the following descriptions, the series on / off circuit of Figure 1b will now be represented by an equivalent impedance (2), whose value Zs theoretically varies between two values: infinite impedance for the case where the switch is open (by default ) and Z0 for the case where the user presses the key, closing the switch. The aspects described above for the parallel on / off mechanism apply analogously to the serial on / off mechanism, with the appropriate adaptations.

Although commercial switches are considered by way of example, other variants may also be used. In an alternative implementation the two fixed contacts of the switch could be printed on the printed circuit board itself and a third movable metal part would be used to contact the two fixed parts. As shown in Figure 2, a single key remote control can be obtained simply by integrating the parallel (1) or series (2) circuit with an antenna (9) (input impedance Z0). In this simple configuration, a characteristic impedance transmission line Z0 and arbitrary length will suffice to connect the circuit (1) or (2) to the antenna (9). 13

While a single-key remote control - which is nothing more than an RFID tag with an on / off functionality - can be seen as easy to implement, a multi-button remote already brings added challenges. In the embodiments of this document, a set of requirements is guaranteed: 1) By default all chips are silent and no ID is read by the reader; 2) Only the RFID chip associated with the button pressed by the user is active at any instant; 3) Only the chip of the previous paragraph is connected to the antenna at any instant; 4) Only the ID of the wanted chip is read by the reader; 5) The remaining chips remain silent; 6) The remaining chips do not interfere with the active chip;

In order to meet the above requirements the system has two important features: individual chip control (as explained above) and sharing of the antenna by the various chips. Antenna sharing is achieved by the use of a 1: N multi-port network. (Similar structures are used in the already known SPNT switches, typically applied in the distribution / multiplexing. form, but in an original way). Such an arrangement should be able to dynamically connect the active (user-selected) chip to the antenna, while ensuring that the remaining chips do not interfere with the asset. Without restrictive character to configurations that may be derived from this, some possible configurations are presented in figures 2b to 2g.

In Figure 2b) a remote control with two keys is shown using the parallel activation / deactivation mechanism. By default the circuits (1) are in idle mode with an impedance Ζρ = 0Ω at points A and C (as described above). In this mode, it is not possible for the RFID reader to access the chip IDs since their antenna terminals are short-circuited. As soon as the user presses one of the keys, the respective chip (for example the one on the right) switches to active mode, showing at point A an impedance Zp = Z0. The second chip (left), which remains in idle mode, has a zero impedance at point C (Ζρ = 0Ω). This zero impedance will undergo a phase rotation of 90 ° (plus a multiple of 180 °), imposed by the transmission line (10), being transformed into an open circuit at point B. This means that the inactive chip (left) will have no influence on the parallel association of impedances at point B. Thus, antenna (9) will " see " only the active chip of the

right, while the idle chip on the left will remain invisible, not interfering with the rest of the circuit. A generalization of this configuration to N keys (star configuration) is shown in Figure 2d). In order to facilitate reading the figures of the present document, the various indices k of each figure are integers which are independent, i.e. being equal or different from each other, and also including the value zero.

Figure 2c shows a two-button remote using circuits with serial on / off mechanism (2) and transmission lines with a multiple length of 180 °. A similar reasoning to the previous one can be done, with the difference that in this case the chip in idle mode has an infinite Zs impedance. Thus, the infinite impedance of the inactive chip will also be transformed into an infinite impedance (open circuit) by a multiple phase rotation of 180 °, imposed by the transmission line (11). As in the circuit of Figure 2b), here again the inactive chip will not influence the parallel association of impedances at the central point. The antenna will only be connected to the active chip, allowing it to be read by the RFID reader, while the inactive chip will remain invisible to the rest of the circuit. This configuration can be generalized to a cascaded configuration with N keys as shown in Figure 2e).

In Figure 2f) a remote control with N keys using the parallel activation / deactivation mechanism and tree configuration is shown. This configuration can be seen as a combination of the configurations of Figure 2b) and 2c) or can be seen as the cascading interconnection of two or more star interconnects. Conversely, a multiple cascade star is also possible. The 1: N network used here corresponds to an association of multiple pairs of transmission lines (10) (vertically) interconnected by portions of lines (11) (horizontally). In turn, the arrangement shown in Figure 2g) corresponds to an N-key remote, based on a hybrid configuration cascade (as in Figure 2e) + tree (Figure 2f) and using both serial and parallel activation / deactivation mechanisms .

Figures 3a and 3b relate to the communication between the proposed remote control (18) and the device to be controlled (12) or (23). The remote control 18 communicates with the device to be controlled 12 or 23 by an RFID reader 13 or 20. This communication is done remotely (wirelessly) using radio signals (represented by 19) through the remote control's antennas (9) and the RFID reader (16) and (17). Figure 3a) relates to the case where an RFID transceiver (13) is embedded in the device to be controlled (12). Such a transceiver is comprised of an RFID transmitter 14, 16 whose function is to send data and power to the remote control 18, and an RFID receiver 15 for receiving data from the remote control. In this case, where the RFID transceiver is embedded in the device to be controlled, the control unit 14 is common to both the RFID transceiver 13 and the device to be controlled 12.

Alternatively, as shown in Figure 3b), an adaptation system may be mounted externally on the device to be controlled, in this particular case a device that uses infra-red for remote control. Such an adaptation system is composed of an RFID reader 20 and an RFID-Infrared interface 22 which bridges the RFID reader 20 and the device to be controlled 23. In this configuration, the RFID reader has its own control unit (21), which can also be used to control the RFID-Infrared interface (22). In this implementation, there is no direct electrical contact between the RFID reader (20) and the device to be controlled (23), the communication being via infrared. The use of the external adapter is useful, for example, to integrate the remote control system without batteries here proposed in eg. televisions, more commonly in already installed equipment using for ex. infrared, thus ensuring compatibility.

A battery-operated remote control system based on passive RFID technology is described, in which the remote control does not require batteries or batteries, consisting of an antenna, a plurality of N passive RFID chips and N keys, and a multi-port network 1: N, where each key on the remote control is associated with a chip enabling the device to be controlled (eg TV) via an RFID reader to uniquely or uniquely identify the key pressed by the user. 17

In a preferred embodiment, each key may activate two or more chips, for example through multi-pole switches.

In a preferred embodiment, the remote control is comprised of an antenna, N keys and respective N passive RFID chips, wherein a 1: N multi-port network ensures antenna sharing by the N chips.

In a preferred embodiment, there are mechanisms for activating and deactivating the RFID chips, using contact switches, in order to enable the user to activate and deactivate the chips.

In a preferred embodiment, the 1: N multi-port network interconnects the antenna and the N chips so as to ensure that only the active chip is connected to the antenna of the remote at each instant, allowing it to be read by the RFID reader, while the remaining chips remain silent without interfering with the active chip.

In a preferred embodiment, the 1: N multi-port network is composed of microwave transmission lines or co-planar waveguides, or another, capable of sharing / multiplexing a single antenna to the N RFID chips .

A preferred embodiment describes appropriate multi-port network arrangements with the N chips and N switches to ensure that: by default all chips are silent and no ID is read by the RFID reader; only the RFID chip associated with the pressed key is active at any instant; only the active RFID chip is connected to the antenna of the remote control at any instant; only the ID of the intended chip is read by the reader; the remaining chips remain silent; the remaining chips do not interfere with the active chip; 18

A preferred embodiment describes a reading system to be incorporated internally or externally in the device to be controlled, whose function is to identify the key pressed at each instant by reading the respective RFID chip. A preferred embodiment describes an RFID reader embedded in the device to be controlled.

A preferred embodiment describes a system to be externally mounted on the device to be controlled incorporating an RFID reader and an RFID-IV interface / adaptation system.

A preferred embodiment includes a method and accounting system / system interface proposed with prior art.

The described embodiments are combinable with each other. The following claims further define preferred embodiments of the present invention.

Application examples

This invention finds applicability in all scenarios in which it is desired to wirelessly control a device. Some examples: - Televisions, Cable TV box, sound equipment and all type of entertainment equipment to replace the current mechanisms of remote control;

Game consoles, for reading the operation of controls, or controls, or game controllers by users; - Garage doors, for controlling one of several doors and / or for controlling one of several functions (up / down / stop / etc);

Keyboards without batteries or batteries, for reading the operation of the keys by the users; 19 - Multi-function cards, for example to choose one of several tariffs or purse available on the same RFID reading card for public transport; - User controlled cards.

Lisbon, August 26, 2014. 20

Claims (14)

RFID communication remote control device comprising: a. an RFID communication antenna (9) with impedance Zo; B. an RFID communication element (1 or 2) for user control which comprises: - an RFID communication chip (3) with its own impedance or adapted equal to ZO; and a normally closed contact switch (5) in parallel with said RFID communication chip, referred to as a controllable parallel RFID communication element (1), or a normally open contact switch (6) in series with said RFID communication, referred to as controllable element of RFID communication series (2); said contact switch being connected to a compensation impedance (7 and 8) so that, at the operating frequency of said device, the contact switch (5 or 6) when closed operates as a short circuit; and said RFID communication chip (3) is connected directly or indirectly to said RFID communication antenna (9). Device according to the preceding claim comprising: a. a plurality of N said controllable RFID communication elements series (2), or parallel (1), or series and parallel; 1 b. a multi-port network 1: N, said antenna (9) interconnecting the plurality of N controllable RFID communication elements (1 or 2), comprising, for said interconnection, transmission lines with predefined phase rotation; in which controllable parallel RFID communication elements (1), if any, are interconnected each with the RFID communication antenna (9) by a 90 ° phase rotation optionally added with a positive or negative multiple of 180 ° (10) ); and wherein the controllable serial RFID communication elements (2), if present, are each interconnected with the RFID communication antenna (9) by a positive or negative 0 ° or multiple phase rotation of 180 ° (11). Device according to the preceding claims comprising only controllable parallel RFID communication elements (1) in the RFID communication antenna (9). The device of claims 1-3 which comprises only controllable serial elements (2) of RFID communication cascaded to the RFID communication antenna (9). The device of claims 1-3 which comprises only controllable controllable RFID communication elements (1) coupled in cascade of two or more stars, to the RFID communication antenna (9). A device according to the preceding claim comprising controllable serial RFID communication elements (2) in each of said cascades. A device according to the preceding claims wherein said compensating impedance is an LC loop (7 and 8), wherein the inductance L (8) includes the inductance of the contact switch (5 and 6). A device according to the preceding claim wherein the inductance L (8) is the inductance of the contact switch (5 or 6). The device of the preceding claims wherein the switch (5 or 6) is a contact switch. A device according to the preceding claims, wherein the switch (5 or 6) comprises a contact sliding piece, a contact tip piece, a contact rotating part, a pivot contact piece, or a contact lifting piece. A device according to the preceding claims wherein the 1: N multi-port network comprises microwave transmission lines and / or co-planar waveguides. A RFID communication remote control system of an apparatus comprising one or more of the RFID communication remote control devices of the preceding claims (18); and an RFID communication reader (13 or 20) for reading chips from said remote control devices (18) by RFID communication. A system as claimed in the preceding claim wherein said RFID communication reader (13) is contained in said remotely controlled apparatus (12). The system of claim 12 further comprising an RFID-IV interface (22) connected to said RFID communication reader (20) and connected by infrared to the remotely controlled apparatus (23). Lisbon, August 26, 2014. 4