System, device and program

Abstract

To provide a convenient system and the like capable of more secure remote control than before.SOLUTION: The system comprises a first device and a second device that are capable of wireless communication, where the wireless communication of the first device and the second device is of a spread spectrum type. At least one of the first device and the second device is portable by a user, and signals transmitted by the one device include a signal for operating a function of the other of the first device and the second device. The spread spectrum type of the wireless communication of the first device and the second device is preferably the LoRa type, and uses a sub-gigahertz band, preferably a sub-gigahertz band frequency channel having a bandwidth wider than the bandwidth of a channel in a frequency band less than the sub-gigahertz band.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to, for example, a system, an apparatus, a program, and the like. [Background technology]

[0002] Remote engine starting devices (engine starters) that remotely start the engine for the purpose of warming up the engine and regulating the temperature inside the vehicle are becoming popular. This remote engine starting device is installed in the vehicle and includes a relay drive circuit that controls the engine start and the operation of electrical equipment, and a main control circuit that controls the relay drive circuit when it receives a start command signal. The start command signal is sent from a wireless remote control transmitter (portable device) that the user holds close by. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3959146 Summary of the Invention [Problem to be solved by the invention]

[0004] For systems like engine starters, which utilize a portable device and another communication device to remotely control the device, the portable device has traditionally used a specified low-power radio with a 420 MHz frequency band, FSK (Frequency Shift Keying) modulation, and an output of 10 mW or 1 mW. The problem with such systems is that each company has a roughly uniform communication distance limit. While the communication distance varies depending on the conditions, it is typically around 4 km in line of sight, and in some cases, it can be as low as a few hundred meters. Companies are competing with each other like apples to apples, with each company competing to achieve the maximum distance. While each company has had difficulty breaking out of this situation and has a strong desire to do something about it, the obstacle to breaking out is largely due to industry common sense and stereotypes.

[0005] An object of the present invention is to provide a system or the like that can perform remote control more reliably and is easier to use than, for example, conventional systems. [Means for solving the problem]

[0006] (1) For example, a system may be provided that includes a first device and a second device capable of wireless communication, the wireless communication between the first device and the second device is performed using a spread spectrum method, at least one of the first device and the second device is portable by a user, and a signal transmitted by one of the devices includes a signal that activates a function of the other of the first device or the second device.

[0007] In this way, users can operate the functions of devices by remote control using wireless communication over a significantly longer distance than conventional FSK methods other than the spread spectrum method (frequency spread method), which is far superior to the conventional methods used by other companies. According to the results of experiments conducted by the inventors, it was possible to operate the functions of devices over a distance roughly twice as long as conventional methods. For example, if the distance at which wireless communication was reliably possible with the conventional FSK method was 1 km, the spread spectrum method enabled communication over a distance of more than 2 km, more than twice that distance.

[0008] At least one of the first device and the second device portable by the user may be any device, for example, a golf navigation system, and preferably a handheld device or a remote controller (hereinafter also referred to as "remote control" for short). For example, a signal transmitted from the remote control may include a signal for activating a function of the other of the first device and the second device. At least one of the first device and the second device portable by the user may be particularly equipped with a function for inputting instructions from a user and may be configured to transmit a signal for activating a function of the other device based on the input instruction. The function for inputting instructions from the user may be any device that can input instructions, but may be a sensor capable of detecting user movements, etc., and may particularly be equipped with a means for inputting user instructions. At least one of the first device and the second device portable by the user may be a wearable terminal that can be attached to the body. Preferably, at least one of the first device and the second device portable by the user is a device that can be held in the hand and may be equipped with a function for inputting instructions by hand. Preferably, the device has a means for inputting instructions by pressing with a finger, and more preferably, the means for inputting instructions is a switch.

[0009] The other of the first device and the second device may be any device, for example, a device that can be carried by a user, preferably a device that is not portable by a user, for example, a device fixed to an object, and more preferably a device installed indoors. When fixed to an object, it may be fixed to the ground, for example, and preferably fixed to a gas, electricity, or water meter. When fixed to the ground, it may be a water sprinkler, for example. When fixed to a gas, electricity, or water meter, it may be a terminal device that transmits meter reading data to a remote control. When installed indoors, it may be installed in a golf clubhouse or an automobile, for example. When installed in a clubhouse, it may be used as a digital signage, for example. When installed in an automobile, it may be used as an in-vehicle device, for example. Most preferably, when the first device is a portable device, the second device may be fixed to another object, or when the second device is a portable device, the first device may be fixed to another object.

[0010] The system of the present invention may be any system, but may be, for example, a system used in consumer devices or various industrial devices, and particularly a system used in automobile-related devices such as the engine starter described above, allowing a user to appropriately remotely control various devices.

[0011] For example, a system for use with consumer devices may be a system in which one of the first device or the second device that can be carried by the user is a remote control, and the other is a device fixed to the ground, and the signal transmitted from the remote control includes a signal that activates a function of the device.

[0012] In a system for use with consumer devices, it is desirable that one of the first device or the second device, which can be carried by the user, is a portable device, and the other is a transmitter fixed to a gas, electricity, water meter, etc. The signal transmitted from the transmitter to the portable device should include meter reading data and a signal that causes the portable device to compile the meter reading data (a signal that activates a function of the portable device).

[0013] In particular, a wireless communication system using a standard called "Wi-SUN (Wireless Smart Utility Network)" is preferable, which includes a terminal device fixed to a gas, electricity, or water meter, and collects meter reading data using a portable device or the like via wireless communication. Using the system of the present invention with Wi-SUN allows users to collect meter reading data from more remote locations than ever before, minimizing the travel effort required for data collection. For example, when reading an electricity meter in a mountainous area far from roads accessible by car and accessible only by foot, a meter reader carrying a portable device is more likely to be able to collect meter reading data (hereinafter also referred to as "meter information") within the range accessible by car, thereby increasing the possibility of shortening the travel distance even if walking is required after traveling by car. In particular, the portable device should be portable and portable, allowing the user to move around on foot and input instructions manually.

[0014] More preferably, this system would have the first device be a golf navigation system and the second device be a digital signage system installed in the clubhouse. In particular, the signal transmitted from the golf navigation system would include a signal that activates the display and tallying functions of the digital signage. In this case, it would be possible to display the rankings of players entered into the golf navigation system during a round on the digital signage, thereby saving the user the trouble of tallying up player results.

[0015] A system for use in automobile-related equipment may be, for example, a system for use in an automobile engine starter or car security system, with the first device being a remote control and the second device being an in-vehicle device. In particular, the signal transmitted from the remote control may include a signal for activating a function of the in-vehicle device, and the signal transmitted from the in-vehicle device may include a signal for activating a function of the remote control. Preferably, the signal transmitted from the remote control is transmitted based on a user instruction.

[0016] With conventional engine starters and car security systems, for example, in large apartment buildings, parking lots could be located far from the user's room, making them inaccessible. This problem was particularly pronounced in tower apartments. Furthermore, for example, concrete walls could block radio waves, making it impossible to use the system without going out onto a balcony. However, even in such cases, the present invention allows the user to more reliably activate the functions of the other device than before. For example, the engine starter and car security functions can be more reliably activated than before. Therefore, for example, even in cases where the user previously had to move to a location, such as a window or balcony, where radio waves could reach the vehicle in the parking lot more easily, the user is now more likely to be able to activate the engine starter or car security system by operating it from a location indoors, such as next to the bed.

[0017] Furthermore, for example, a system for automobile-related devices equipped with the above-mentioned remote control (portable device) and in-vehicle device can be combined with a wireless communication system that collects Wi-SUN meter information, etc., so that the in-vehicle device acts as a gateway (a gateway) to transmit meter information generated in the home to the portable device. Specifically, for example, the in-vehicle device can receive information such as gas, electricity, and water meter reading data and power generation data from a solar or other power generation device installed in the home from a Wi-SUN device in Wi-SUN mode (a modulation method other than spread spectrum), and the in-vehicle device can then transfer this received information to the portable device (remote control) carried by the user in spread spectrum mode. In this way, users can receive information such as meter reading data within a cycling range, which is wider than the conventional walking range. For example, under conditions where radio waves only reach about 1 km in conventional Wi-SUN mode (a modulation method other than spread spectrum), a range of 6 km can be achieved by lowering the bit rate using spread spectrum. An area with a diameter of 1 km centered on a residential house is considered to be within the daily living area (walking distance), while an area with a diameter of 6 km is considered to be within the local living area (if necessary, refer to Table 5 on page 6, page 32, and Table 4-3 on page 37 of the following electronic technical information (Ishihara Hiroshi, "Basic Research on Daily Living Areas (Part 2)", [online], March 2008, Nagoya Urban Center, [accessed July 5, 2016], Internet <URL: http: / / www.nui.or.jp / user / media / document / investigation / h19 / nichijo.pdf>). In addition, almost everything can usually be done within the local living area (biking distance) from one's home (if necessary, refer to page 11 of the following electronic technical information: Ichimura Machio, "Method for Analyzing Commercial Demand Based on Living Areas," [online], June 2006, Community Builders' Net, [accessed July 5, 2016], Internet <URL: http: / / www.geocities.jp / non_non_net2006 / p_rep / seikatukenn2.pdf>).

[0018] Preferably, the first device is fixed to an object, and the second device is portable by the user. The user carrying the second device can activate the functions of the first device at the location of the object where the first device is fixed, without using the second device. The second device is carried by the user and moves along with the user's walking or cycling from the location of the object where the first device is fixed as a base point (e.g., the starting point of the movement). The second device returns to the base point (e.g., the original starting point as the end point after traveling to a predetermined destination) when the user moves to the location of the object where the first device is fixed. The "walking or cycling" distance should be a line-of-sight distance of 5 km to 20 km. For example, the base point may be a home, and the user may be an elderly person with dementia. Alternatively, the base point may be a car, and the user may walk from the car, shop at a shopping center, start the engine, and return to the car. For example, the base point may be an automobile, and the user may walk from the automobile to their home after returning home, and the next morning, start the engine of the automobile from inside the home and then return to the automobile. Alternatively, the base point may be a clubhouse, and the user may walk around the golf course while playing, and return to the clubhouse after playing.

[0019] Alternatively, for example, the first device may be a single base unit installed in a nursing facility, and the second device may be a set of slave units carried by multiple residents of the nursing facility. For example, each slave unit may store a different ID, and the base unit may store a correspondence between the ID stored in each slave unit and the name of the person carrying the slave unit. Each slave unit transmits radio waves containing ID data using a spread spectrum method at regular intervals (e.g., every minute). The base unit checks the ID data contained in the received radio waves and the received signal strength indicator (RSSI) of the received radio waves. When the RSSI of the received radio waves falls below a set value, the base unit displays the approximate distance from the base unit to the slave unit that transmitted the radio waves, calculated based on the RSSI level, and the name of the person associated with the ID. The "RSSI setting value" may be determined in advance by calculating the relationship between the distance between the base unit and the slave unit and the RSSI value, and stored in the base unit, so that the distance can be entered and set in the base unit. Alternatively, "when the RSSI falls below a set value" may be when the RSSI level reaches that equivalent to that outside the care facility, based on the difference in RSSI measured in advance between inside and outside the facility and set in advance.

[0020] The base unit may have a function for selecting a person's name stored in advance from a list or the like, and a function for wirelessly transmitting a signal requesting a response to a slave unit with an ID corresponding to that person's name. If the received ID is its own ID and a response is requested from the base unit, the slave unit wirelessly transmits its own ID and level information regarding the received electric field strength. The base unit determines and displays the position of the slave unit (e.g., distance from the base unit) from the level of electric field strength of the received ID.

[0021] Furthermore, it is preferable that the sub-units have a function for relaying wireless signals inquiring from the base unit between them. For example, the base unit may have a "normal search button (search without relay)" and a "search with relay" button. When the "normal search button" is pressed, it requests responses from all sub-units within the range of the base unit's radio waves, including their IDs and field strength levels. On the other hand, when the "search with relay" button is pressed, it requests responses from all sub-units within the range of the base unit's radio waves and from all sub-units within the range of the radio waves from those sub-units. The responses (e.g., the IDs and field strength levels of other sub-units) are relayed by the sub-units between the base unit and other sub-units. It is also possible to have further relaying between sub-units, and it is preferable to limit the number of relays between sub-units. Furthermore, the base unit and sub-units may each be equipped with a location detector such as a GPS, so that only sub-units within a range specified by the base unit from the location of the base unit are relayed.

[0022] In a "spread spectrum" communication, for example, a narrowband signal modulated to be transmitted is spread to a wideband signal using a predetermined spreading method to reduce the power density, and then transmitted from the transmitting side. At the receiving side, the received signal is despread to obtain the original narrowband signal with a high power density. Furthermore, the "spread spectrum" is particularly suitable for a configuration in which, even if the spread signal received at the receiving side is a weak signal below the so-called noise floor, the signal is despread to return it to the original narrowband signal with a high power density, and the original narrowband signal is demodulated and reproduced as the signal intended to be transmitted. This configuration makes it possible to receive signals that have attenuated below the noise floor over long distances.

[0023] In communications using the "spread spectrum method," modulation of the spread signal performed on the transmitting side and demodulation of the spread signal performed on the receiving side may be performed using a hardware modulator and demodulator, or may be performed using a software defined radio. In particular, it is preferable to use an IC chip that performs the calculations corresponding to such modulation and demodulation.

[0024] Any communication method may be used as the "spread spectrum method," but it is particularly preferable to use a method that increases communication distance even at the expense of communication speed. For example, a frequency hopping method may be used. It is preferable to use a method other than a direct sequence spread spread method. More preferably, the "spread spectrum method" is a method (hereinafter referred to as a "chirp method") in which a chirp signal is generated by continuously changing the frequency, and a signal based on the data to be transmitted is spread and modulated by this (hereinafter referred to as a "chirp method"). It is particularly preferable to combine the chirp method with other methods. For example, it is preferable to combine the chirp method with at least one of a frequency hopping method and a direct sequence spread spread method. For example, it is most preferable to use the LoRa method, which will be described in detail later, as the "spread spectrum method." Conversely, conventional modulation methods other than the spread spectrum method include, in addition to the above-mentioned FSK method, OOK (On-Off Keying), GFSK (Frequency Shift Keying), MSK (Minimum Shift Keying), GMSK (Gaussian Minimum Shift Keying), etc. (hereinafter, these modulation methods will be collectively referred to as "FSK, etc.").

[0025] Furthermore, "at least one of the first device and the second device" that is "portable by the user" may be any device, and may be, for example, a mobile communication device, a mobile information device, a wearable terminal, etc. Furthermore, "at least one of the first device and the second device" that is "portable by the user" may be, for example, a non-dedicated device that can perform functions other than remote control, but may particularly be a dedicated device for remote control, such as a remote controller.

[0026] Furthermore, the "signal transmitted by the one device" may be configured to include a signal that activates a function of the other of the first device or the second device. For example, in the case of an engine starter or car security, the signal may include a signal for starting, stopping, or changing settings of the device. For example, in the case of an engine starter or car security, the signal may include a signal for activating an alarm function from the device to a portable device or remote control. Preferably, the "signal transmitted by the one device" may include a signal other than a signal that activates a function of the other device. For example, in the case of an engine starter, the "signal other than a signal that activates a function of the other device" may be data detected by a sensor installed in the vehicle, such as the current cabin temperature, or in the case of a car security, the degree of impact to the vehicle.

[0027] Furthermore, the "signal transmitted by the one device" may be configured to include a start signal, a stop signal, etc. for consumer devices such as water sprinklers or various industrial devices. Furthermore, the "signal transmitted by the one device" may be configured to include a signal such as player performance information entered into a golf navigation system, etc. Furthermore, when the system of the present invention is used in devices such as gas, electricity, or water meters that use standards such as Wi-SUN, the "signal transmitted by the one device" may be configured to include various data such as meter reading data.

[0028] For example, if the first device is a portable device such as a remote control and the second device is an in-vehicle device, the portable device may be configured to operate in single receive mode and the in-vehicle device may be configured to operate in continuous receive mode. This configuration can extend the battery life of the portable device and allow the in-vehicle device to more reliably capture signals transmitted from the portable device. In this configuration, it is desirable for the in-vehicle device to transmit the same information multiple times. This configuration can reduce the occurrence of missed readings due to disturbances in the portable device. It is even more desirable for the in-vehicle device to have a function for transmitting a signal to switch to continuous receive mode from the in-vehicle device to the portable device, and for the portable device to operate in continuous receive mode when it receives this signal. In this configuration, it is particularly desirable to configure the device to operate in continuous receive mode for a fixed period of time. This communication mode can be implemented, for example, by using the communication chip "SX1272" described below.

[0029] "Single receive mode" is, for example, a mode in which only one packet is received within a set time, and in particular, when communicating at a fixed receive timing, it is recommended to configure the receiver circuit to be turned on only at the required receive timing. This makes it possible to reduce power consumption during standby for reception. "Continuous receive mode" is, for example, a mode in which signals are received continuously.

[0030] (2) The wireless communication between the first device and the second device using a spread spectrum method may be a LoRa method.

[0031] In this way, users can break away from the current situation where the distance at which remote control is possible is roughly uniform.

[0032] A wireless system using a spread spectrum method, particularly the LoRa method (hereinafter also referred to as a "LoRa wireless system"), when designed for the same communication distance as an FSK method, can communicate at a higher transmission bit rate (hereinafter simply referred to as "bit rate", "data rate" or "transmission speed"). A higher bit rate shortens communication time, so a user can obtain a system that can quickly activate a function of one of a first device and a second device when transmitting a signal to activate the function of the other device from either one of the devices.

[0033] In particular, it is preferable that at least one of the first device and the second device, which are portable by the user, has a function for inputting instructions from the user and transmits a signal to activate the function of the other device based on the input instruction. With this configuration, it is possible to obtain a system that quickly responds to input operation of instructions.

[0034] Preferably, the bit rate in the LoRa system is set low. This allows for higher sensitivity. Most preferably, the bit rate is set to the lowest possible setting. In particular, the bit rate of either the first or second device, whichever is portable, is set to the lowest possible setting. This allows a user to transmit a signal from the portable device to activate a function of the other device from a greater distance than before, thereby activating the function of the other device. Furthermore, for example, the bit rate of the portable device may be set lower than the bit rate of the device whose function is activated by the signal transmitted from the portable device. Furthermore, the system may include the configurations (3) and (3-1) described below. Experimental results by the inventors have shown that this configuration achieves a transmission distance approximately four times longer and a coverage area approximately 16 times larger than that of the conventional 420 MHz band FSK system.

[0035] It is desirable to set the bit rate low in systems that transmit and receive small amounts of digital information, and even more desirable to set the bit rate low when transmitting digital information such as for automobile engine starters and car security systems.

[0036] LoRa wireless communication can be implemented using, for example, the SX1272 communication chip manufactured by SEMTECH, which performs the modulation and demodulation of the signals described above through calculations.

[0037] (3) The wireless communication between the first device and the second device may use a sub-gigahertz band, and may use a channel in the sub-gigahertz band whose bandwidth is wider than the bandwidth of a channel in a frequency band below the sub-gigahertz band.

[0038] In this way, a user can operate the functions of a device by remote control using wireless communication, using a smaller device than before and over a longer distance than before. While radio waves generally have a shorter propagation distance in the sub-gigahertz band than in frequency bands below the sub-gigahertz band, this problem of short propagation distance can be solved by using a channel in the sub-gigahertz band whose bandwidth is wider than that of a channel in the frequency band below the sub-gigahertz band. For example, it is advisable to set a channel in the sub-gigahertz band whose bandwidth is wider than that of a channel in the frequency band below the sub-gigahertz band.

[0039] Furthermore, for example, the frequency of an oscillator provided in the first device and the second device for performing wireless communication may be set as in (3). In particular, for example, the setting of the frequency for wireless communication may be performed by a control unit provided in the first device and the second device, and the set frequency may be set as in (3). Preferably, the control unit is a computer, and a value corresponding to the set frequency is written into a register of the computer.

[0040] (3-1) The wireless communication between the first device and the second device should be a specified low-power radio communication, using the sub-gigahertz band, and using a sub-gigahertz frequency where the transmittable power used is greater than the transmittable power in a frequency band below the sub-gigahertz band.

[0041] The "sub-gigahertz frequency band" may be the 400 MHz band, preferably 449.7125 to 449.8250 MHz, 449.8375 to 449.8875 MHz, or 469.4375 to 469.4875 MHz, or more preferably 426.0250 to 426.1375 MHz, 426.0375 to 426.1125 MHz, 429.1750 to 429.2375 MHz, 429.2500 to 429.7375 MHz, or 429.8125 to 429.9250 MHz. In each of these bands, the channel bandwidth may be, for example, 12.5 kHz, and, particularly, 25 kHz in the 426.0375 to 426.1125 MHz band. Furthermore, the transmittable power may be set to, for example, 1 mW in the frequency bands below the sub-gigahertz band, 426.0250 to 426.1375 MHz and 426.0375 to 426.1125 MHz, and may be set to, for example, 10 mW in the other bands.

[0042] The "sub-gigahertz band" may be, for example, a frequency band slightly lower than 1 GHz, preferably 800 to 950 MHz. More preferably, it is the 920 MHz band defined by Japanese regulations. Even more preferably, it is a band with a center frequency of 928.15 to 929.65 MHz, and most preferably, it is a band with a center frequency of 916.0 to 928.0 MHz. In the band with a center frequency of 928.15 to 929.65 MHz, the channel bandwidth may be, for example, 100 kHz, and in the band with a center frequency of 916.0 to 928.0 MHz, the channel bandwidth may be, for example, 200 kHz. Furthermore, channels used in the sub-gigahertz band should have a bandwidth at least four times larger than the bandwidth of channels in frequency bands below the sub-gigahertz band. Preferably, a channel with a bandwidth of 200 kHz is selected, which is eight times the 25 kHz bandwidth of a channel in the 426.0375 to 426.1125 MHz band. More preferably, a sub-gigahertz channel with a bandwidth of 200 kHz is selected, which is 16 times the 12.5 kHz bandwidth of a channel in the 426.0250 to 426.1375 MHz, 429.1750 to 429.2375 MHz, 429.2500 to 429.7375 MHz, or 429.8125 to 429.9250 MHz band. Furthermore, within the sub-gigahertz band, the transmittable power should be, for example, 1 mW in the 916.0 to 920.4 MHz and 928.15 to 929.65 MHz bands, and, for example, 20 mW in the other bands. A channel to be used in the sub-gigahertz band should preferably have a transmittable power of 20 mW, which is 20 times the transmittable power of 1 mW or twice the transmittable power of 10 mW in a frequency band below the sub-gigahertz band.

[0043] In the 400 MHz band, which is included in the "sub-gigahertz frequency band," Japanese regulations at the time of filing allocated a bandwidth of 12.5 kHz or 25 kHz per channel. Meanwhile, in the sub-gigahertz band, there is the 920 MHz band, which allocates a bandwidth of 100 kHz or 200 kHz per channel. As such, the 920 MHz band is a particularly good sub-gigahertz band, as it offers a wider bandwidth per channel than the 400 MHz band, which is a sub-gigahertz frequency band. While the 400 MHz band has a narrower bandwidth per channel than the 920 MHz band, its radio waves have the advantage of reaching farther distances and being less directional and more prone to diffraction, making them easier to receive even behind distant obstacles (mountains or buildings).

[0044] The inventors have found that the "channel to be used" should be one of the 15 channels in the 920.6 to 923.4 MHz band, with a 200 kHz bandwidth and 200 kHz intervals, and the 14 channels in the 920.7 to 923.3 MHz band, with a 400 kHz bandwidth and 200 kHz intervals, and in particular, at least one of the six channels with center frequencies of 922.4 MHz, 922.6 MHz, 922.8 MHz, 923.0 MHz, 923.2 MHz, and 923.4 MHz (all with a 200 kHz bandwidth). In particular, it is desirable to have a configuration that allows switching between some of these channels, and preferably a configuration that automatically switches to one of these channels that is determined to have no signal present through a busy determination. These channels may also be configured to use a wider bandwidth by combining multiple adjacent channels; for example, five adjacent channels out of the six channels mentioned above may be combined to use a bandwidth of 1000 kHz.

[0045] Furthermore, a "channel" may be, for example, a frequency band allocated for use in communications, particularly a frequency band allocated by the laws and regulations of the country of use, and particularly a frequency band allocated by the laws and regulations of Japan.

[0046] When determining whether a channel is busy (determining whether a signal is present and therefore transmission is prohibited), the signal level of the spread spectrum method is determined by, for example, CAD (Channel Acceleration and Delay Timer). The CAD function may be configured to detect the presence of a spread spectrum signal at a level so low that it cannot be detected by RSSI. The busy state determination may be configured to be -130 dBm or higher for a spread spectrum signal, and -80 dBm or higher for signals using other modulation methods. This allows for more accurate channel busy determination, making it possible to operate device functions over long distances by remote control using wireless communication.

[0047] Table 1 shows all cases where the presence of a signal is confirmed by the CAD function and RSSI and where it is not confirmed. The top row of each column indicates the Busy determination content, and the bottom row indicates what kind of signal is allowed to be transmitted. Table 1 shows cases where the first and second devices are capable of transmitting signals using modulation methods other than spread spectrum. In Table 1, when the presence of a signal is confirmed by the CAD function, it is marked as "CAD present," and when it is not confirmed, it is marked as "CAD absent." When the presence of a signal is confirmed by RSSI, it is marked as "RSSI present," and when it is not confirmed, it is marked as "RSSI absent."

[0048] [Table 1]

[0049] As shown in Table 1, in the cases of "RSSI present" and "CAD present," (A) the busy state is determined to be due to the presence of both a spread spectrum signal and a signal using a modulation method other than spread spectrum, or (B) the busy state is determined to be due to the presence of a relatively strong spread spectrum signal (-80 dBm or higher). In the case of (A), the transmission of signals using all modulation methods is prohibited, while in the case of (B), the transmission of signals using modulation methods other than spread spectrum is possible. Furthermore, even in the case of (A), a spread spectrum signal with a different bandwidth and spreading rate from the existing spread spectrum signal is possible.

[0050] If "RSSI exists" and "CAD does not exist," the busy state is determined to be due to the presence of a signal using a modulation method other than spread spectrum. Since no spread spectrum signal is present, it is possible to transmit a spread spectrum signal.

[0051] When "RSSI not present" and "CAD present", the busy state is determined to be due to the presence of a spread spectrum signal, and since there are no signals using modulation methods other than spread spectrum, it is possible to transmit signals using modulation methods other than spread spectrum. Furthermore, even if a signal uses spread spectrum, it can be transmitted as long as the bandwidth and spreading rate differ from those of the existing spread spectrum signal.

[0052] In the case of "No RSSI" and "No CAD", there is no Busy judgment, and since there are no signals using the spread spectrum method or signals using modulation methods other than the spread spectrum method, signals using all modulation methods can be transmitted.

[0053] (4) The strength of the signal transmitted from the first device or the second device may be equal to or lower than the noise floor.

[0054] This significantly reduces the possibility of interference with signals using modulation methods other than spread spectrum, such as FSK. The signal strength can be kept below the noise floor by, for example, reducing the transmission power, or by transmitting the signal at a high spreading factor that keeps the signal strength below the noise floor. While a higher spreading factor slightly reduces the transmission speed of the transmitted signal, it also has the advantage of improving communication sensitivity and extending communication distance. Therefore, this allows users to remotely control the device over longer distances than before. The "noise floor" should be set to -80 dBm.

[0055] (5) The wireless communication between the first device and the second device using the spread spectrum method may be configured so that signals can be transmitted with the same power at one of the quarter portions of the bandwidth of the channel used from both ends of the bandwidth to the inside of the bandwidth, and at the center of the bandwidth.

[0056] This allows users to operate device functions by remote control using wireless communication over longer distances than conventional systems. Systems capable of high modulation efficiency and high transmission bit rates can be implemented using, for example, spread spectrum and LoRa. On the other hand, FSK has low modulation efficiency because the signal transmission power decreases at the high-frequency and low-frequency ends of the bandwidth and the signal extends outside the bandwidth.

[0057] In the wireless communication between the first device and the second device using the spread spectrum method, it is preferable that signals can be transmitted at the same power near both ends of the bandwidth of the channel used, in the vicinity of one-quarter of the bandwidth from the ends to the inside of the bandwidth, and near the center of the bandwidth. More preferable that signals can be transmitted at the same power near at least one end of the bandwidth of the channel used and near the center. Even more preferable that signals can be transmitted at the same power over the entire bandwidth of the channel used.

[0058] In the configuration (5), it is particularly preferable to configure the power for transmitting signals outside the bandwidth of the channel to be less than a specified value. This will result in a higher modulation efficiency because the amount of signal that extends outside the bandwidth will be less than the specified value. Given the same communication distance in a communication system, the higher the modulation efficiency, the higher the bit rate at which communication can be achieved.

[0059] At least one of the first device and the second device should preferably be a device whose power consumption does not change even when the transmission bit rate is changed. Increasing the transmission bit rate and shortening the communication time reduces the current consumption of the device, thereby reducing the power consumption of the system. In particular, it is preferable to use a battery as the power source for the device. This can extend the battery life (hereinafter also referred to as "battery lifespan"). This allows the user to minimize the hassle of battery replacement, etc.

[0060] At least one of the first device and the second device may be a device whose power consumption increases when the transmission bit rate is increased. In particular, it is preferable to set the transmission bit rate so that the reduction in transmission power due to the shortened communication time exceeds the increase in power consumption caused by the increase in the transmission bit rate. In this way, overall power consumption can be reduced and battery life can be extended.

[0061] Furthermore, for example, a first device and a second device capable of wireless communication may be provided, and the wireless communication between the first device and the second device may be configured to use a method that enables transmission at the same power in the center portion of the entire width and at one edge of the periphery, instead of or in addition to the spread spectrum method. In particular, a configuration that enables signal transmission at the same power across the entire bandwidth of the channel used may be configured. For example, the wireless communication between the first device and the second device may use an OFDM modulation method, instead of or in addition to the spread spectrum method. In particular, Wi-Fi HaLow (IEEE 820.11ah) may be used.

[0062] The wireless communication between the first device and the second device should be configured to use GFSK modulation instead of or in addition to the spread spectrum method. It is preferable to use GFSK modulation at a speed of several hundred bits per second or less. Sigfox is even more preferable. However, the best method at present is the spread spectrum method, and the LoRa method (2) is particularly preferable.

[0063] Furthermore, wireless communication between the first device and the second device may be performed via wireless network communication, but it is preferable to perform it as one-to-one communication between the first device and the second device. For example, the communication chip "SX1272" may be configured to use a SyncWord value of, for example, 0x12 instead of the 0x34 used in LoRaWAN. Preferably, a value other than 0x34 or 0x12 should be used. This reduces the possibility of interference with commercially available devices that perform LoRaWAN wireless communication.

[0064] (6) Of the first device and the second device, the one that is portable by the user may preferably have a built-in antenna used for the wireless communication.

[0065] This allows users to use devices with simple configurations where the antenna is not exposed to the outside, particularly portable devices with excellent portability, as portable devices. This is because a wireless system using spread spectrum technology can use an antenna with lower antenna gain when designed for the same communication distance and communication bit rate as a wireless system using FSK technology.

[0066] This effect is particularly pronounced when using a wireless system that uses the LoRa method, as in (2). While typical spread spectrum wireless systems (such as WLAN and WCDMA (registered trademark)) strive for interference prevention and high bit rates, the LoRa method significantly improves sensitivity by spreading low-bit rate signals over a wide band using spread spectrum while consuming a large bandwidth. Therefore, by adopting the LoRa communication method, it is possible to further miniaturize the built-in antenna. This allows for a system that is unobtrusive and stress-free to use, even when the user carries the portable device in a pocket, etc.

[0067] As the LoRa wireless system has high communication sensitivity, it can use a smaller antenna with low gain. Therefore, by adopting the LoRa wireless system, it is possible to use a remote control (portable device) that has a built-in antenna but can achieve the same radio wave range as a remote control using a conventional rod antenna, providing a system with highly portable remote controls (portable devices) for users.

[0068] Preferably, the configuration (3) is provided. More preferably, the configuration (3-1) is provided. Even more preferably, the configurations (3) and (3-1) are provided. Most preferably, the configurations (2), (3) and (3-1) are provided. In this way, the advantage of including a built-in antenna is particularly great.

[0069] (7) It is preferable that the user can directly or indirectly change the magnitude of the transmission power of the signal.

[0070] In this way, the user can use the system with the optimal transmission power depending on the environment in which the user uses the system. For example, when the distance between the first device and the second device is short and the communication environment is expected to be relatively good, the transmission power can be minimized by setting the transmission power low within a range that does not cause problems in signal transmission. The device that transmits the signal, either the first device or the second device, can use a battery as its power source. This allows the user to extend battery life and reduce the frequency of battery replacement, etc. On the other hand, when prioritizing reliable signal transmission between the first device and the second device over minimizing the transmission power, the transmission power can be set higher, taking into account the expected communication distance, etc. This ensures reliable signal transmission and allows the user to accurately control the device equipped with the system of the present invention.

[0071] Here, an example of a configuration in which "the magnitude of the transmission power of the signal can be changed directly by the user" is a configuration in which the magnitude of the transmission power of the first device or the second device is set by inputting a power value. By allowing "the magnitude of the transmission power to be changed directly by the user" in this way, the user can accurately adjust the transmission power to a magnitude that is suitable for their own usage conditions.

[0072] An example of a configuration in which the "user can indirectly change the magnitude of the signal transmission power" is a configuration in which the magnitude of the transmission power of the first or second device is set using a relative numerical value or index associated with the power value. Various indexes associated with the power value can be considered, such as "strong," "medium," or "weak," or an index based on the operating mode. In particular, a configuration in which the user can select between a "long-distance communication mode (normal mode)" and a "long-life mode" with a long battery life can be used. This allows the user to choose whether to prioritize battery life or the distance at which the device's functions can be activated by remote control using wireless communication. By allowing the "user to indirectly change the magnitude of the transmission power" in this way, the user can intuitively or intuitively adjust the output transmission power to a level appropriate for their own usage conditions.

[0073] The configuration in which "the user can directly or indirectly change the magnitude of the signal transmission power" may be any configuration, and may be configured to do so via switches (e.g., dip switches) or control devices provided on the non-portable device of the first device or the second device, such as an engine starter or an on-board device in a car security system, and particularly may be configured to do so on the portable device of the first device or the second device, such as a portable device such as a remote control.

[0074] The signal transmission power may be changed by operating an operation unit on a remote controller or other device, for example. The operation unit may be configured as a slider or a slider displayed on a display screen on the remote controller or other device.

[0075] Preferably, the portable one of the first and second devices is configured to be selectable between the above-mentioned "long-distance communication mode (normal mode)" and "long-life mode." In this way, the user can extend the battery life by selecting the long-life mode in an area where communication is possible in the long-life mode, and when communication in the long-life mode becomes impossible in an area farther away than the area where communication is possible in the long-life mode, the user can switch to the long-distance communication mode and activate the functions of the other device by remote control using wireless communication.

[0076] Furthermore, when setting the operation mode according to the magnitude of the signal transmission power, such as "long distance communication mode (normal mode)" or "long life mode," each mode may be set in multiple stages or continuously according to the magnitude of the transmission power. By adopting these methods, the user can easily and accurately adjust the magnitude of the signal transmission power.

[0077] (8) It is preferable that the user can directly or indirectly change the transmission bit rate of the signal.

[0078] In this way, by adjusting the transmission bit rate, the user can use the system under conditions that are optimal for the user's environment. For example, by setting a low transmission bit rate, the user can improve communication sensitivity and ensure a wide communication range. On the other hand, by setting a high transmission bit rate, the user can minimize communication time at the expense of communication sensitivity and communication distance, and can operate the device's functions by remote control using wireless communication over long distances with agile communication operations.

[0079] At least one of the first device and the second device should preferably be a device whose power consumption does not change even when the transmission bit rate is changed. Increasing the transmission bit rate and shortening the communication time reduces the current consumption of the device, thereby reducing the power consumption of the system, particularly the device that transmits the signal. It is particularly preferable to use a battery as the power source for the device. This allows the user to extend battery life and minimize the hassle of battery replacement.

[0080] At least one of the first device and the second device may be a device whose power consumption increases when the transmission bit rate is increased. In particular, it is preferable to set the transmission bit rate so that the reduction in transmission power due to the shortened communication time exceeds the increase in power consumption caused by the increase in the transmission bit rate. In this way, overall power consumption can be reduced and battery life can be extended.

[0081] Here, an example of a configuration in which "the user can directly change the transmission bit rate of the signal" is a configuration in which the transmission bit rate of the first device or the second device is set by inputting a bit rate value. By allowing "the user to directly change the magnitude of the transmission bit rate" in this way, the user can accurately adjust the transmission bit rate to suit their own usage conditions.

[0082] An example of a configuration in which the "user can indirectly change the signal transmission bit rate" is a configuration in which the magnitude of the transmission bit rate of the first or second device is set using a relative numerical value or index associated with the transmission bit rate. Various indexes associated with the transmission bit rate are possible, such as "high, medium, or low," or an index based on the operating mode. In particular, it is preferable to select between a "normal mode" and a "speed mode" that provides fast communication. This allows the user to select whether to prioritize the distance at which the device's functions can be activated by remote control using wireless communication or the speed of communication. By enabling the "user to indirectly change the signal transmission bit rate" in this way, the user can intuitively or intuitively adjust the transmission bit rate to a value appropriate for their own usage conditions.

[0083] The configuration in which "the user can directly or indirectly change the transmission bit rate of the signal" may be any configuration, and may be configured to be performed via switches (e.g., dip switches) or control devices provided on the non-portable device of the first device or the second device, such as an engine starter or an on-board device in a car security system, or in particular, via a portable device of the first device or the second device, such as a remote control.

[0084] Preferably, the portable one of the first and second devices is configured to be selectable between the "normal mode" and the "speed mode." In this way, the user can select the speed mode in an area where communication is possible in the speed mode to make communication operations agile, and when communication in the speed mode becomes impossible in an area farther away than the area where communication is possible in the speed mode, the user can switch to the normal mode to activate the functions of the other device by remote control using wireless communication.

[0085] The transmission bit rate may be changed by operating an operation unit on a remote control or other device, for example. The operation unit may be configured as a slider, or may be configured as a slider displayed on a display screen on the remote control or other device.

[0086] Furthermore, when setting the operating mode according to the magnitude of the transmission bit rate, such as "normal mode" or "speed mode," each mode may be set in multiple stages or continuously according to the magnitude of the transmission bit rate. By adopting these methods, the user can easily and accurately adjust the magnitude of the signal transmission bit rate.

[0087] (9) In the information regarding the strength of the signal received in the last communication between the first device and the second device, if the strength of the signal is equal to or greater than a predetermined value and the transmission is performed within a predetermined time from the reception of the signal in the last communication, the transmission power is reduced, and if the strength of the signal is less than the predetermined value or the transmission is performed after a predetermined time has elapsed from the reception of the signal in the last communication, the transmission power is maintained at least at the transmission power at the time of the last communication.

[0088] This allows a user to optimize transmission power consumption while ensuring reliable signal transmission and reception in the system. For example, if the signal strength received by a device in the last communication is stronger than necessary, the strength of the next transmitted signal may be reduced. Here, since at least one of the first and second devices is portable, even if the signal strength received by the device is stronger than necessary, the distance between the first and second devices may increase over time due to the user's movement, etc. In this way, when adjusting the transmission power for the next communication based on the signal strength received by the device in the last communication, it is preferable to assume a change in the distance between the first and second devices using time as an index and perform the adjustment based on this assumption. In the configuration (9), the transmission power is reduced not only when the signal strength received in the last communication is equal to or greater than a predetermined value, but also when the next signal is transmitted within a predetermined time since the reception of the signal in the last communication. Furthermore, in the configuration (9), the transmission power is maintained at least when the signal strength is less than a predetermined value or when transmission is performed after a predetermined time has elapsed since the reception of the signal in the last communication. This allows users to operate the device's functions remotely over long distances using wireless communication, while reducing transmission power consumption. Furthermore, if a battery is used as the power source, the battery life can be extended, eliminating the need for frequent battery replacement.

[0089] Here, the "predetermined time" may be set based on the distance over which communication between the first and second devices is expected to be established even if the distance between the first and second devices increases, and the assumed speed at which the distance between the first and second devices increases, for example, when the transmission power of the next signal to be transmitted is reduced below the transmission power of the signal transmitted in the last communication. For example, assuming that one of the first and second devices is a portable device such as a remote control and the other is a stationary device that does not move, and assuming a case in which the distance between the first and second devices increases as the user moves on foot, the "predetermined time" may be set based on the relationship between the average walking speed of an average adult, the distance over which communication between the first and second devices is expected to be established after the transmission power is reduced, and the length of the communication distance that is expected to be reduced by the reduction in transmission power. In this way, by using time as an index to estimate changes in the distance between the first device and the second device, setting a "predetermined time" based on this estimated result, and using this predetermined time as one of the criteria for reducing transmission power, even when control is performed to suppress transmission power consumption, the user can operate the device's functions by remote control using wireless communication over long distances without feeling inconvenienced.

[0090] The "predetermined time" for reducing the transmission power may be, for example, between one and two minutes. This "predetermined time" may be constant or may vary depending on the signal strength.

[0091] Here, it is preferable to configure a system in which the first device is a portable device (e.g., a remote control) and the second device is a fixed device (e.g., an in-vehicle device, a household device, or other device that can obtain an external power source). In this way, in a system in which basic control begins with sending commands from the remote control, it is possible to reduce the transmission power consumption of the fixed device. In this case, for example, if the fixed device is configured to use the battery installed in the automobile as its power source, such as an engine starter or car security system, it is possible to minimize the power consumption of this battery.

[0092] It is also advisable to configure a system in which the fixed device periodically transmits a link confirmation signal to the remote control. In this way, the radio wave strength of the link confirmation signal can be monitored and the transmission power of the remote control's transmission signal can be reduced. If the remote control's transmission power can be reduced and its power consumption can be reduced, the life of the battery built into the remote control (portable device) can be extended, eliminating the need for users to frequently replace the battery.

[0093] Furthermore, for example, when the amount of information to be transmitted is large and the information is divided into multiple transmissions, it is preferable to configure the device so that the first transmission is performed with high transmission power and the second and subsequent transmissions are adjusted based on the radio wave intensity of the first transmission. This allows for optimization of transmission power. In this case, it is preferable to configure the device so that a battery is used as the power source. This can extend battery life and minimize the frequency of battery replacement by the user.

[0094] Furthermore, for example, in the case of a car security system, when a sensor detects that some kind of trouble has occurred in the car, a signal can be sent from the in-vehicle device, which is a fixed device, to the remote control, even if no command is sent from the remote control. In this way, when a user who has learned that the car security system is activated operates the remote control to disable the car security system, the transmission power of the remote control's transmission signal can be reduced based on the radio wave strength of the signal previously received from the in-vehicle device, minimizing power consumption in the battery built into the remote control and minimizing the frequency with which the user has to replace the battery.

[0095] Furthermore, it is preferable to configure the system so that a signal can be sent to the fixed device using a remote control, for example. In this way, the remote control can send a setup start command and, based on the radio wave strength of the response signal returned from the fixed device, the transmission power of the signal from the remote control can be reduced, minimizing power consumption of the battery built into the remote control and minimizing the frequency with which the user has to replace the battery.

[0096] A user carrying a remote control may move after receiving a signal in the last communication in the system. Therefore, if the transmission power of the remote control or the fixed device is reduced after a predetermined time has elapsed, the distance between the remote control and the fixed device may become too great, resulting in insufficient radio wave strength and making it impossible to activate the device's functions remotely via wireless communication over long distances. Therefore, it is preferable to reduce the transmission power within a predetermined time and maintain the transmission power after the predetermined time has elapsed. This allows the device's functions to be activated remotely via wireless communication over long distances and extends battery life. This minimizes the frequency with which the user has to perform tedious tasks such as battery replacement.

[0097] Furthermore, the "maintaining at least the transmission power" configuration may be a configuration in which the transmission power is maintained or a configuration in which the transmission power is increased. As in the configuration (9), when the strength of the signal received in the last communication is below a predetermined value or when a predetermined time has elapsed since the reception of the signal in the last communication, the transmission power may be maintained at the transmission power at least at the transmission power level at the time of the last communication. This configuration prevents communication from being terminated due to a decrease in transmission power, thereby ensuring communication stability. This allows the user to operate the device's functions by remote control over long distances using wireless communication without any inconvenience, even when the strength of the signal received in the last communication is weak or a predetermined time has elapsed since the last communication.

[0098] If the "predetermined time" for reducing the transmission power is changed depending on the signal strength, the higher the signal strength, the shorter the predetermined time should be, and the lower the signal strength, the longer the predetermined time should be. However, if the signal strength is below the predetermined value, the transmission power should at least be maintained.

[0099] In the configuration of (9), for example, if communication is not possible with the transmission power lowered, the transmission power is increased, and if communication is still not possible, the transmission power is increased further. When communication is not possible with the transmission power lowered, the transmission power is increased stepwise or continuously, and in particular, it is increased directly to the maximum. In this way, the user can obtain the advantage of being able to minimize power consumption.

[0100] In the configuration (9), for example, the transmission power of the remote control and the fixed device may be set to maximum under normal conditions and automatically reduced, or the user may set the transmission power by operating the remote control or by setting a dip switch on the in-vehicle device. The remote control may also be configured to display the transmission power on its display screen. This allows the user to check the transmission power. The remote control may also be configured to display the strength of the received radio waves on its display screen. This allows the user to use the remote control while checking whether communication is possible based on the displayed radio wave strength.

[0101] (10) In the information regarding the strength of the signal received in the last communication between the first device and the second device, if the strength of the signal is equal to or greater than a predetermined value and the signal is transmitted within a predetermined time from the reception of the signal in the last communication, the transmission bit rate for transmitting the signal is increased, and if the strength of the signal is less than the predetermined value or the signal is transmitted after a predetermined time has elapsed from the reception of the signal in the last communication, the transmission bit rate is maintained at least at the transmission bit rate at the time of the last communication.

[0102] This allows a user to optimize the transmission bit rate while ensuring reliable signal transmission and reception in the system. For example, if the signal strength received by a device in the last communication is greater than necessary, the strength of the next transmitted signal may be reduced. Here, since at least one of the first and second devices is portable, even if the signal strength received by the device is greater than necessary, the distance between the first and second devices may increase over time due to the user's movement, etc. In this way, when adjusting the transmission bit rate for the next communication according to the signal strength received by the device in the last communication, it is preferable to assume a change in the distance between the first and second devices using time as an index and perform the adjustment based on this assumption. In the configuration (10), the transmission bit rate is increased not only when the signal strength received in the last communication is equal to or greater than a predetermined value, but also when the next signal is transmitted within a predetermined time since the reception of the signal in the last communication. Furthermore, in the configuration (10), the transmission bit rate is at least maintained when the signal strength is less than a predetermined value or when transmission is performed after a predetermined time has elapsed since the reception of the signal in the last communication. This allows users to operate the device's functions remotely over long distances using wireless communication, while reducing transmission power consumption. Furthermore, if a battery is used as the power source, the battery life can be extended, eliminating the need for frequent battery replacement.

[0103] Here, the "predetermined time" may be set based on the distance over which communication between the first and second devices is expected to be established even if the distance between the first and second devices increases, and the assumed speed at which the distance between the first and second devices increases, for example, when increasing the transmission bit rate of the next transmitted signal from a level higher than the transmission bit rate at the time of the last communication. For example, assuming that one of the first and second devices is a portable device such as a remote control and the other is a stationary device, and assuming that the distance between the first and second devices increases as the user moves on foot, the "predetermined time" may be set based on the relationship between the average walking speed of an average adult, the distance over which communication between the first and second devices is expected to be established after the increase in the transmission bit rate is reduced, and the length of the communication distance that is expected to decrease due to the increase in the transmission bit rate. In this way, by using time as an index to estimate changes in the distance between the first device and the second device, setting a "predetermined time" based on this estimated result, and using this predetermined time as one of the criteria for increasing the transmission bit rate, even if control is performed to increase the transmission bit rate, the user can operate the device's functions by remote control using wireless communication over long distances without feeling inconvenienced.

[0104] The "predetermined time" for increasing the transmission bit rate may be, for example, between one and two minutes. This "predetermined time" may be constant or may vary depending on the signal strength.

[0105] Furthermore, the configuration of "maintaining at least the transmission bit rate" may be a configuration of maintaining the transmission bit rate or a configuration of decreasing the transmission bit rate. As in the configuration (10), when the strength of the signal received in the last communication is below a predetermined value or when a predetermined time has elapsed since the reception of the signal in the last communication, the transmission bit rate may be maintained at the transmission bit rate at least at the transmission bit rate at the time of the last communication. This configuration prevents communication from being terminated due to an increase in the transmission bit rate, thereby ensuring communication stability. This allows the user to operate the device's functions by remote control over long distances using wireless communication without any inconvenience, even when the strength of the signal received in the last communication is weak or a predetermined time has elapsed since the previous communication.

[0106] In a communication system with the same bandwidth, the transmission bit rate, sensitivity (travel distance), and transmission power are inversely proportional to each other. In other words, in the system of the present invention, increasing the transmission bit rate reduces the distance (decreased sensitivity) for the same bandwidth and transmission power, shortening the distance at which a device's functions can be activated by remote control using wireless communication. However, this shortens the transmission time and speeds up the system's communication operations. Here, if the received signal strength is high, communication is possible even with low sensitivity, so communication is possible even if the transmission bit rate is increased. Therefore, in the configuration (10), it is recommended to increase the transmission bit rate as the received radio wave strength increases. This allows a user to quickly activate a function from either the first or second device when transmitting a signal to activate the other device's function.

[0107] (11) In the spread spectrum wireless communication, a plurality of spreading factors can be set, and the spreading factor may be changed when a predetermined condition is satisfied.

[0108] In this way, the user can build a wireless system that is extremely difficult to intercept.

[0109] The "changing of the spreading factor" may be configured to be performed in a predetermined pattern. The "predetermined pattern" of the "changing of the spreading factor" may be configured to be random or in a predetermined order. Here, in the system of the present invention, the higher the spreading factor, the longer the distance at which the device's functions can be activated by remote control using wireless communication. Therefore, it is particularly preferable to configure the system to employ the maximum spreading factor and the spreading factor one step lower. In such a configuration, the pattern of the changing of the spreading factor may be configured to alternate between the maximum spreading factor and the spreading factor one step lower in a predetermined pattern. In this way, it becomes possible to activate the device's functions by remote control using wireless communication over a long distance and in a manner that is difficult to intercept.

[0110] "When a specified condition is met" may be configured to occur every time one packet is sent, every time a packet with a specified amount of data is sent, or every time a specified amount of time has passed.

[0111] The "spreading factor" may be, for example, the ratio (C / B) of the spreading code rate (also called "chip rate"; C) to the transmission bit rate (B).

[0112] (12) It is advisable to enable communication by switching the channel used for communication.

[0113] In this way, the frequency band allocated for communication is switched during communication, allowing users to obtain a system that is less susceptible to interference between spread spectrum communication systems. In this case, the receiver and transmitter switch channels in sync. For example, if the band used for wireless communication is the 920 MHz band, it is recommended to use six channels with center frequencies of 922.4 MHz, 922.6 MHz, 922.8 MHz, 923.0 MHz, 923.2 MHz, and 923.4 MHz, which can be switched between. Note that channels other than these may also be used.

[0114] Spread spectrum methods, particularly LoRa methods, allow for significantly longer communication distances than FSK methods. Therefore, when a communication method with a long communication distance, such as LoRa, is adopted, there is a high possibility of interference occurring due to other users' communications interrupting the communication range. Therefore, when using spread spectrum methods, particularly LoRa methods, it is preferable to suppress interference by appropriately switching the channel used for communication. This allows users to communicate stably without being affected by other users' devices using spread spectrum communication methods nearby.

[0115] (13) A system according to any one of (1) to (12), comprising a vehicle control device that starts a drive device of a vehicle based on a predetermined vehicle start signal, and a start permission device capable of transmitting a start permission signal to the vehicle control device to permit the start of the drive device, the system receiving a PIN code transmitted from a PIN code transmitter that is portable by a user and capable of transmitting a predetermined PIN code, and indirectly transmitting the PIN code to a vehicle to which the start permission signal is transmitted by the start permission device based on the received PIN code and a reference code provided in the start permission device, wherein the system is configured to: The wireless communication with the first device may be selectable between a spread spectrum method and a communication method other than the spread spectrum method, the first device may be portable by a user and may receive the PIN code from the PIN code transmitter, and may transmit to the second device a signal including a conversion code obtained by converting the received PIN code in a predetermined manner and a start instruction signal, and the second device may be mounted on the vehicle and may convert the received conversion code into the PIN code and transmit the converted PIN code to the start permission device, and may transmit the vehicle start signal to the vehicle control device upon receiving the start instruction signal.

[0116] In this way, in an automobile equipped with a start permission device (so-called immobilizer) that uses a personal identification code, for example, the user can start a drive device such as an engine or motor using a remote control (a first device that can be carried by the user) without leaving the personal identification code transmitter inside the vehicle, but while carrying it with him or her. Generally, due to security concerns, for example, the personal identification code transmitter and the start permission device cannot send and receive a personal identification code unless they are in close proximity, and starting of the drive device cannot be permitted. However, in this way, even if the personal identification code transmitter and the start permission device are far apart, the personal identification code transmitted from the personal identification code transmitter is relayed between the remote control (a first device that can be carried by the user) and the in-vehicle device (a second device mounted on the vehicle) and can be received by the start permission device, allowing starting of the drive device to be permitted.

[0117] An example of a configuration for "indirectly transmitting" a PIN code is one in which a first device receives a PIN code from a PIN code transmitter, converts the PIN code into a different conversion code, and transmits it to a second device, and the second device converts the received conversion code back into the original PIN code before transmitting it to the start permission device.

[0118] Regarding the second device, the configuration of "mounting it on a vehicle" preferably means a configuration in which the device is originally attached to the vehicle at the time of vehicle manufacture by the automobile manufacturer, and in particular, a configuration in which the device is retrofitted to a vehicle that has already been sold.

[0119] The start instruction signal transmitted by the first device may be configured to be issued in response to an instruction from a user.

[0120] The wireless communication between the first device and the second device may be configured to select between a spread spectrum method and a communication method other than the spread spectrum method. In this way, even if it is difficult to permit the start of the drive device using one of the methods, the possibility of permitting the start of the drive device can be increased. The "selection of the communication method" may be configured in any way, for example, via switches (e.g., dip switches) or a control device provided on an in-vehicle device (a second device mounted on a vehicle), and particularly, via a remote control (a portable first device). Furthermore, the selection of the communication method may be configured to be performed based on the operation of an operating unit provided on the remote control or another device. The operating unit may be configured, for example, as a slider, or may be configured as a slider displayed on a display screen provided on the remote control or another device.

[0121] It is preferable to configure the system so that the user can select between a mode in which the PIN code transmitted from the PIN code transmitter is relayed between a first communication device carried by the user and a second communication device installed in the vehicle (hereinafter referred to as "relay mode"), and a mode in which the PIN code is not relayed (hereinafter referred to as "non-relay mode"). In this way, users and retailers can support both vehicle models with immobilizers and vehicle models without immobilizers by simply preparing one type of system equipped with a remote control and an onboard device, and can also accommodate users of vehicle models equipped with immobilizers who do not mind leaving a PIN code transmitter in their vehicle. The configuration for selecting between the "relay mode" and the "non-relay mode" can be configured, for example, by providing a selection means such as a switch on the onboard device and selecting the mode using this selection means.

[0122] When "Relay mode" is selected, it is recommended to configure the wireless communication to be in continuous mode using a communication method other than spread spectrum. In this case, the "communication method other than spread spectrum" should be FSK or similar. "Continuous mode" is a mode in which the level of the DIO2 / DATA pin is transmitted as is (without going through the FIFO).

[0123] When "non-relay mode" is selected, it is preferable to select "long distance mode" or "short distance mode." In "long distance mode," it is preferable to select a packet mode of the spread spectrum method for wireless communication, and in particular, it is preferable to select a packet mode of the LoRa method. In "packet mode," it is preferable to select a packet mode of the SPI (Serial Peripheral It is recommended to configure the device so that data provided via the FIFO is sent as packets.

[0124] The "short-distance mode" may be configured such that wireless communication is performed in a packet mode using a communication method other than spread spectrum, and preferably such that wireless communication is performed in a packet mode using spread spectrum with a higher transmission bit rate than in the long-distance communication mode, and more preferably such that wireless communication is performed in a LoRa system with a higher transmission bit rate than in the long-distance communication mode. A communication device that can select between the LoRa system and the FSK system and between the continuous mode and the packet mode may be, for example, the above-mentioned communication chip "SX1272."

[0125] Any of the configurations (1) to (13) may be arbitrarily combined to form a configuration. Also, any of the components described in the configurations (1) to (13) may be arbitrarily combined to form a configuration.

[0126] (14) For example, it may be configured as the first device in any of the systems described in (1) to (13) above.

[0127] (15) For example, it may be configured as a second device in the system described in any one of (1) to (13) above.

[0128] Such devices may be, for example, devices for systems used in the above-mentioned consumer devices and various industrial devices, or devices for wireless communication systems that collect meter reading data, and may particularly be configured as devices for systems used in automobile-related devices. Devices for systems used in automobile-related devices may be configured as remote controls or in-vehicle devices, for example, as devices for systems used in engine starters.

[0129] (16) For example, the functions described in any of (1) to (13) above may be configured as a program for causing a computer to realize the functions. [Effects of the Invention]

[0130] According to the present invention, it is possible to provide a system or the like that can perform remote control more reliably and is easier to use than conventional systems, for example. [Brief explanation of the drawings]

[0131] [Figure 1] FIG. 1 is a block diagram showing an outline of an example of the configuration of an engine starter using a system according to the present invention. [Figure 2] FIG. 2 is an external view of an engine starter using the system according to the present invention, where (a) is a front view of the remote control and (b) is a perspective view of the junction unit. [Figure 3] FIG. 3 shows a display on the display unit of the remote control and a sound emitted from the remote control when the engine is started using the remote control. [Figure 4] FIG. 4 shows the display on the display unit of the remote control and the sound emitted from the remote control when the engine status is checked using the remote control. [Figure 5] FIG. 5 is a diagram showing the display unit of the remote control and the sound emitted from the remote control when idling extension is performed using the remote control. [Figure 6] FIG. 6 shows a display on the display unit of the remote control and a sound emitted from the remote control when the engine is stopped using the remote control. [Figure 7] FIG. 7 shows the display on the display unit of the remote control and the sound emitted from the remote control when the door is locked or unlocked using the remote control. [Figure 8] FIG. 8 is an explanatory diagram of the first remote control registration method. [Figure 9] FIG. 9 is an explanatory diagram of the second remote control registration method. [Figure 10] FIG. 10 is a block diagram showing an outline of another example of the configuration of an engine starter using the system according to the present invention, and shows the case where the user carries and uses the original key in a car equipped with an immobilizer. [Figure 11]FIG. 11 is a block diagram showing an outline of another example of the configuration of an engine starter using the system according to the present invention, and shows the case where the original key is placed inside a car equipped with an immobilizer. [Figure 12] FIG. 12 is a block diagram showing an outline of another example of the configuration of an engine starter using the system according to the present invention, in which the system is used in an automobile not equipped with an immobilizer. DETAILED DESCRIPTION OF THE INVENTION

[0132] A preferred embodiment of the present invention will be described below with reference to the accompanying drawings. The system of this embodiment is a system used in an engine starter that starts an automobile engine (drive unit) by remote operation using a remote controller (hereinafter referred to as "remote control"). Note that the present invention is not limited to the examples shown in the embodiments described below, and it will be readily apparent to those skilled in the art that other embodiments may be possible within the scope of the claims, in accordance with the teachings and spirit of the present invention.

[0133] 1. Engine starter configuration Fig. 1 is a block diagram showing an outline of an example of the configuration of an engine starter using the system according to the present invention. Fig. 2 is an external view of the engine starter using the system according to the present invention, in which Fig. 1(a) is a front view of the remote control and Fig. 2(b) is a perspective view of the junction unit.

[0134] As shown in FIG. 1, the engine starter 10 includes a remote control 20 (first device) and a junction unit 40 (second device) mounted on the vehicle. The remote control 20 can be held by the user for operation and transportation. As shown in FIG. 2(a), the remote control 20 includes a display unit 24 on the front of a flat, approximately rectangular case 22 with rounded top and bottom edges, extending from the center to the top in the vertical direction. The display unit 24 is a monochrome, two-tone segment-type LCD screen. The display unit 24 incorporates a seven-color backlight, which lights up when an operation of an operation button 26 is detected, improving visibility. However, because leaving the backlight on all the time consumes battery power quickly, the backlight is turned off after a set period of time. This period of time can be changed by the user (e.g., 5 seconds, 10 seconds, or 20 seconds (default is 5 seconds)). A mode in which the backlight is not lit at all is also available. The color of the backlight can also be changed by user settings (for example, white / yellow / purple / blue / orange / green / indigo). The display unit 24 displays the setting items and contents during setting, and can display the operating status of the system and engine during use. Examples of various displays on the display unit 24 are shown in Figs. 3 to 8, which will be described later.

[0135] The case 22 has operation buttons 26 below the display unit 24 on the front side. The operation buttons 26 are used for operation and include a start button 26a, an engine button 26b, and a stop button 26c. The start button 26a also functions as a lock button, and the stop button 26c also functions as an unlock button. As shown in FIG. 2(a), the start button 26a on the left side and the stop button 26c on the right side are in contact with each other, and the engine button 26b is located so as to be in contact with the lower parts of the start button 26a and the stop button 26c. A rod-type antenna 28 is provided on the upper left side of the case 22. The antenna 28 is pulled out fully when the remote control 20 is in use and pushed in fully when not in use. A battery cover (not shown) is provided on the back side of the case 22.

[0136] The remote control 20 includes a case 22 and includes a wireless communication circuit 30, a control unit 32, and a battery 34, all of which are shown in FIG.

[0137] The junction unit 40 is attached to the vehicle after purchase. As shown in Fig. 2(b), the junction unit 40 includes a first connector 42 connected to the vehicle's key cylinder connector and vehicle connector via cables, a second connector 44 connected to brake detection lines, door lock lines, door unlock lines, etc. via cables, a third connector 46 connected to a temperature sensor 54, and a fourth connector 48 connected to an antenna unit 56.

[0138] The first connector 42, the key cylinder side connector, and the vehicle side connector are connected so that the same signal that is sent from the key cylinder to the vehicle side via the cable when the key cylinder is operated with a key is sent from the junction unit 40 to the vehicle side via the first connector 42 and the cable when the remote control 20 is operated. Therefore, for example, when an operation to start the engine is performed using the remote control 20, the same vehicle start signal as when an operation to start the automobile engine using the key is sent to the vehicle control device on the vehicle side, and the engine starts.

[0139] The door lock line and door unlock line connected to the second connector 44 are connected to a door control device on the vehicle side. When the door is locked or unlocked using the remote control 20, the same door lock signal or door unlock signal that is sent to the door control device when the door is locked or unlocked using a key or a remote control originally provided on the key (a remote control separate from the remote control 20) is sent from the junction unit 40 to the door control device, and the door is locked or unlocked.

[0140] Each remote control 20 is assigned a unique ID, and the junction unit 40 operates based on a signal received from a remote control 20 whose ID is paired with the junction unit 40. Therefore, for example, even if an operation to start the engine is performed using an unpaired remote control 20, the junction unit 40 does not respond to the vehicle start signal transmitted from the remote control 20, and the engine cannot be started.

[0141] Junction unit 40 includes therein wireless communication circuit 50 and control unit 52 shown in Fig. 1. Junction unit 40 is powered by a battery provided in the automobile.

[0142] Both the remote control 20 and the junction unit 40 are equipped with the communication chip "SX1272" manufactured by SEMTECH, and the wireless communication circuit 30 of the remote control 20 and the wireless communication circuit 50 of the junction unit 40 are both configured around this communication chip. The wireless communication circuit 30 of the remote control 20 is connected to an antenna 28, and the wireless communication circuit 50 of the junction unit 40 is connected to an antenna unit 56.

[0143] Both wireless communication circuit 30 and wireless communication circuit 50 can switch between six channels, CH33 to CH38, in the 920 MHz sub-gigahertz band. The center frequencies of the channels are 922.4 MHz for CH33, 922.6 MHz for CH34, 922.8 MHz for CH35, 923.0 MHz for CH36, 923.2 MHz for CH37, and 923.4 MHz for CH38. Each channel has a bandwidth of 200 kHz and a transmittable power of 20 mW. Wireless communication between remote control 20 and junction unit 40 is specified low-power radio.

[0144] The 200 kHz bandwidth of these channels is 16 times the 12.5 kHz bandwidth of the channels in the bands 426.0250 to 426.1375 MHz, 429.1750 to 429.2375 MHz, 429.2500 to 429.7375 MHz, or 429.8125 to 429.9250 MHz used in conventional engine starters. Furthermore, the 20mW transmittable power of these channels is 20 times the 1mW transmittable power of 426.0250 to 426.1375MHz or 426.0375 to 426.1125MHz used in conventional engine starters, and twice the 10mW transmittable power of 429.1750 to 429.2375MHz, 429.2500 to 429.7375MHz, or 429.8125 to 429.9250MHz.

[0145] Wireless communication between the remote control 20 and junction unit 40 is carried out by the wireless communication circuit 30 and the wireless communication circuit 50. Radio waves used for wireless communication between the remote control 20 and junction unit 40 are transmitted and received via the antenna 28 of the remote control 20 and the antenna unit 56 of the junction unit 40. Wireless communication between the remote control 20 and junction unit 40 is carried out using the LoRa method, which is a spread spectrum method. Furthermore, wireless communication between the remote control 20 and junction unit 40 involves transmitting signals at the same power in one of the quarter portions of the bandwidth from both ends of the bandwidth of the channel being used, and in the center of the bandwidth.

[0146] The control unit 32 of the remote control 20 and the control unit 52 of the junction unit 40 each include a microcomputer equipped with a CPU, ROM, RAM, flash memory, various peripheral circuits, interfaces, etc. The control units 32 and 52 use a boot loader recorded in ROM to load the OS and application programs recorded in the flash memory onto the RAM, and execute the OS and application programs in the RAM to perform various processes and realize various functions. Unless otherwise noted, all functions are realized by the processing of the control units 32 and 52. The frequency or channel of the oscillator for wireless communication provided in the wireless communication circuit 30 of the remote control 20 and the wireless communication circuit 50 of the junction unit 40 is written to a register in the microcomputer provided in the control unit 32 and the control unit 52.

[0147] 2. How to use and operate the engine starter Next, the use and operation of the engine starter 10 will be described.

[0148] 2-1.Starting the engine 3 shows the display on the display unit of the remote control and the sound emitted from the remote control when starting the engine using the remote control. (a) to (i) in the following description correspond to (a) to (i) in the figure, respectively.

[0149] (a) When starting the engine of the car, the engine button 26b is pressed until a confirmation beep is heard from the remote controller 20. The display unit 24 displays "E" in a flashing state.

[0150] (b) Next, while "E" is flashing (for about 3 seconds), press the start button 26a until the remote control 20 emits the "Do-Re-Mi-Fa-So" sound. The display unit 24 displays "START" along with a transmission animation, and a start instruction signal is sent from the remote control 20. When the junction unit 40 recognizes the start instruction signal, it sends a response signal back to the remote control 20. As shown in (b1), the transmission animation shows three horizontal lines lined up one above the other moving from right to left in order from the top, and then two vertical lines moving from right to left, repeating this action.

[0151] (c) While waiting for a response signal from the junction unit 40, the backlight of the display unit 24 slowly blinks and a reception waiting animation is displayed in which the horizontal bars 24a light up in sequence from left to right.

[0152] (d) When the remote control 20 receives a response signal from the junction unit 40, the remote control 20 emits a receiving sound "Sofa Mire Do." Here, if the cabin temperature display setting is ON, the current cabin temperature is displayed on the display unit 24 for a certain period of time based on the temperature information contained in the response signal, and then the temperature display disappears and the system waits for reception of an engine start confirmation signal. The temperature information is the cabin temperature detected by the temperature sensor 54.

[0153] (e) On the other hand, when the cabin temperature display setting is OFF, when the remote control 20 emits the receiving sound "Sofa Mire Do," the display 24 displays "oK" for a certain period of time, after which the oK display disappears and the system waits for the reception of an engine start confirmation signal.

[0154] The junction unit 40 sends a vehicle start signal to the vehicle control device to start the engine. When the engine starts, the junction unit 40 detects that the engine has started and sends an engine start confirmation signal to the remote control 20. The vehicle start signal sent by the junction unit 40 is the same as the vehicle start signal sent from the key cylinder when an operation to start the engine is performed using a key.

[0155] (f) When the remote control 20 receives the engine start confirmation signal transmitted from the junction unit 40, the receiving sound "Do Re Mi Fa So Fa Mi Re Do" is emitted from the remote control 20. Here, if the auto-stop is disabled, the display unit 24 displays the engine start animation 24b and the idling setting time.

[0156] (g) On the other hand, when auto-stop is enabled, when the remote control 20 emits the received sound "Do-Re-Mi-Fa-So-Mi-Re-Do," the display unit 24 displays the engine start animation 24b and "AUTo." Auto-stop is a function that automatically stops idling if the cabin temperature reaches a preset temperature while idling in order to prevent unnecessary idling of the vehicle. If the cabin temperature at the time of engine start is within ±2°C of the set temperature, the idling time is fixed to 5 minutes.

[0157] During idling, the junction unit 40 emits a series of beeps to notify the user that the vehicle is idling.

[0158] If the junction unit 40 is unable to detect engine start, it will restart (retry) the engine twice.

[0159] (h) When a retry operation is performed, "RT" flashes on the display unit 24 to notify the user of the retry operation.

[0160] (i) If the engine does not start even after the second retry operation, a retry failure signal is sent from the junction unit 40, and the remote control 20 that receives the retry failure signal emits a "beep beep beep" sound, and "ER" flashes on the display 24, and the retry operation is stopped. Even if the retry setting is turned off, the display on the display 24 will show the same message as in (i).

[0161] 2-2.Checking the engine condition 4 shows the display on the display unit of the remote control and the sound emitted from the remote control when checking the engine status using the remote control. (a) to (i) in the following explanation correspond to (a) to (i) in the figure, respectively.

[0162] (a) To check the engine status, press the engine button 26b until a confirmation beep is heard from the remote controller 20. The display unit 24 will show "E" in a flashing state.

[0163] (b) Next, while "E" is flashing (for about 3 seconds), press the engine button 26b again until the "do-re-mi-fa-so" sounds are emitted from the remote control 20. The display unit 24 displays "chK."

[0164] (c) On the display unit 24, a transmission animation is displayed following "chK", and an engine state confirmation signal is transmitted from the remote control 20. When the junction unit 40 recognizes the engine state confirmation signal, it transmits a response signal back to the remote control 20.

[0165] (d) While waiting for a response signal from the junction unit 40, the backlight of the display unit 24 slowly blinks and a reception waiting animation is displayed in which the horizontal bars 24a light up in sequence from left to right. If the engine fails to start, a start error sound can be heard by pressing the engine button 26b twice.

[0166] (e) When the cabin temperature display setting is ON, the remote control 20 emits a receiving sound "Sofa Mire Do," and the cabin temperature is displayed on the display unit 24 based on the temperature information contained in the response signal. The temperature information is the cabin temperature detected by the temperature sensor 54. When the cabin temperature display setting is OFF, this display is not performed.

[0167] (f, g) After displaying the cabin temperature, the idling time is displayed on the display unit 24. Here, (f) if the auto-stop is disabled, in the "idling state", the remaining idling time is displayed on the display unit 24. (g) In the "engine stopped state", the set idling time is displayed on the display unit 24.

[0168] (h, i) On the other hand, when the auto-stop is enabled, (h) in the "idling state", the idling elapsed time is displayed on the display unit 24. (i) in the "engine stopped state", "AUTO" is displayed on the display unit 24.

[0169] 2-3.Extending idling time During idling using the engine starter according to this embodiment, the idling can be extended by 10 minutes once for the set idling time.

[0170] 5 is a diagram showing the display unit of the remote control and the sound emitted from the remote control when idling extension is performed using the remote control. (a) to (h) in the following explanation correspond to (a) to (h) in the figure, respectively.

[0171] (a) To extend the idling time, press the engine button 26b until a confirmation beep is heard from the remote controller 20. The display unit 24 will show a flashing "E."

[0172] (b) Next, while "E" is flashing (for about 3 seconds), press the start button 26a until the remote control 20 emits the "Do-Re-Mi-Fa-So" sound. The display unit 24 displays "START" along with a transmission animation, and an idling time extension signal is sent from the remote control 20. When the junction unit 40 recognizes the idling time extension signal, it sends a response signal back to the remote control 20.

[0173] (c) While waiting for a response signal from the junction unit 40, the backlight of the display unit 24 slowly blinks and a reception waiting animation is displayed in which the horizontal bars 24a light up in sequence from left to right.

[0174] (d) When the remote control 20 receives a response signal from the junction unit 40, the remote control 20 emits the receiving sound "Do Re Mi Fa So Fa Mi Re Do," and (e, f) the display unit 24 alternately displays "Ido" and "+10," notifying the user that the idling time has been extended.

[0175] (g, h) Here, when the auto stop is enabled, the idling extension is disabled, the remote controller 20 emits the receiving sound "Do Re Mi Fa So Fa Mi Re Do," and the display alternates between the elapsed time and "Ido."

[0176] 2-4. Stopping the engine When the engine is started by the engine starter according to this embodiment, the engine can be stopped by the remote control 20.

[0177] 6 shows the display on the display unit of the remote control and the sound emitted from the remote control when the engine is stopped using the remote control. (a) to (d) in the following explanation correspond to (a) to (d) in the figure, respectively.

[0178] (a) When stopping the engine of the car, the engine button 26b is pressed until a confirmation beep is heard from the remote controller 20. The display unit 24 displays "E" in a flashing state.

[0179] (b) Next, while "E" is flashing (for about 3 seconds), press the stop button 26c until the remote control 20 emits the "do-re-mi-fa-so" sound. The display unit 24 displays "STOP" along with a transmission animation, and a stop instruction signal is sent from the remote control 20. When the junction unit 40 recognizes the stop instruction signal, it sends an engine stop signal to the vehicle control device to stop the engine, and sends a response signal back to the remote control 20. The engine stop signal sent by the junction unit 40 is the same signal as the engine stop signal sent from the key cylinder when an operation to stop the engine is performed using a key.

[0180] (c) While waiting for a response signal from the junction unit 40, the backlight of the display unit 24 slowly blinks and a reception waiting animation is displayed in which the horizontal bars 24a light up in sequence from left to right.

[0181] (d) When the remote control 20 receives a response signal from the junction unit 40, the remote control 20 emits a receiving sound "So Mi Re Do Re," the display unit 24 displays "oK," and an engine stop animation is displayed to notify the user that the engine has stopped.

[0182] 2-5. Door lock / unlock operation The remote control 20 of the engine starter according to this embodiment can be used to lock and unlock the doors of the vehicle.

[0183] 7 shows the display on the display unit of the remote control and the sound emitted from the remote control when locking or unlocking the door using the remote control. (a) to (h) in the following explanation correspond to (a) to (h) in the figure, respectively.

[0184] (a) To lock the door, press the start button 26a, which also serves as the lock button, until a confirmation beep is heard from the remote control 20. The display unit 24 flashes "padlock in locked state."

[0185] (b) Next, while "LOCKED PADLOCK" is flashing (for approximately 3 seconds), press the start button 26a again until the remote control 20 emits the "Do-Re-Mi-Fa-So" sound. "LOCKED PADLOCK" is displayed momentarily on the display unit 24, and a lock instruction signal is sent from the remote control 20. When the junction unit 40 recognizes the lock instruction signal, it sends a door lock signal to the door control device via the second connector 44 and the door lock line, and after the door control device locks the door, it sends a response signal back to the remote control 20.

[0186] (c) While waiting for a response signal from the junction unit 40, the backlight of the display unit 24 slowly blinks and a reception waiting animation is displayed in which the horizontal bars 24a light up in sequence from left to right.

[0187] (d) When the remote control 20 receives a response signal from the junction unit 40, the remote control 20 emits a receiving sound “Sofamiredo” and the display unit 24 displays “Padlock in locked state” and “oK,” notifying that the door is locked.

[0188] (e) To unlock the door, press the stop button 26c, which also serves as the unlock button, until a confirmation beep is heard from the remote control 20. The display unit 24 will flash an "unlocked padlock."

[0189] (f) Next, while "Unlocked Padlock" is flashing (for approximately 3 seconds), press the stop button 26c again until the remote control 20 emits the "Do-Re-Mi-Fa-So" sound. "Unlocked Padlock" is displayed momentarily on the display unit 24, and an unlock instruction signal is sent from the remote control 20. When the junction unit 40 recognizes the unlock instruction signal, it sends a door unlock signal to the door control device via the second connector 44 and the door unlock line, and after the door control device unlocks the door, it sends a response signal back to the remote control 20.

[0190] (g) While waiting for a response signal from the junction unit 40, the backlight of the display unit 24 slowly blinks and a reception waiting animation is displayed in which the horizontal bars 24a light up in sequence from left to right.

[0191] (h) When the remote control 20 receives a response signal from the junction unit 40, the remote control 20 emits a receiving sound "Sofamiredo," and the display unit 24 displays "Unlocked padlock" and "oK," notifying that the door has been unlocked.

[0192] 2-6. How to register the remote control The engine starter of this embodiment uses six channels: CH33 (922.4 MHz), CH34 (922.6 MHz), CH35 (922.8 MHz), CH36 (923.0 MHz), CH37 (923.2 MHz), and CH38 (923.4 MHz). The radio frequency is set to CH38 when the product is shipped. If a user attempts to register a remote control again using the same remote control 20 and the same junction unit 40, the wireless communication channel changes to the next channel (or the channel after that if a carrier sense error occurs). The channel changes in this order: CH38 → CH33 → CH34 → ... → CH38 → CH33. Even if the remote control 20 signal cannot be received on CH38 and a channel change is necessary (even if interference occurs), this remote control registration operation is performed near the junction unit 40, so there is no problem. Two remote control registration methods are described below. Since the remote control registration is completed when the product is shipped, the remote control registration process is performed in the event that the remote control in use is lost or breaks down, in order to register the ID of a new remote control in the junction unit and make the new remote control usable.

[0193] (1) First remote control registration method 8 is an explanatory diagram of the first remote control registration method. The first remote control registration method will be described below with reference to the same figure. <Step 1> to <Step 8> described in the following explanation correspond to <Step 1> to <Step 8> in the same figure, respectively. <Step 1> Press and hold both the start button 26a and the stop button 26c on the remote control 20 simultaneously for about 5 seconds. <Step 2> Press the stop button 26c until "Rmd" appears on the display 24 of the remote control 20. If no button is pressed for 20 seconds or more, the remote control 20 will emit a beeping buzzer sound, and the registration will be canceled. <Step 3> Press the engine button 26b on the remote control 20. "REC" will appear on the display 24, and the remote control 20 will emit a series of confirmation beeps. If no button is pressed for 20 seconds or more, the remote control 20 will emit a beep beep beep sound, and the registration will be canceled.

[0194] Steps 4 to 7 below are to be performed while the confirmation beep "beep beep beep..." is being emitted from the remote control 20 (for approximately 40 seconds). If 40 seconds pass before Steps 4 to 7 are completed, the confirmation beep "beep beep beep..." will disappear and the registration will be canceled. <Step 4> Insert the key 62 into the keyhole 64 provided on the vehicle body, and operate the key 62 to switch between ACC → ON → ACC → OFF three times within 7.5 seconds. <Step 5> With the key 62 in the OFF position, the junction unit 40 will emit a beeping sound for 10 seconds, followed by a beep. If you operate the key 62 while the beeping sound is being emitted, the registration will be canceled. <Step 6> Within 7.5 seconds after the junction unit 40 emits a beep, operate the key 62 to switch OFF → ACC → ON → ACC → OFF three times. The junction unit 40 will emit a beep. If 7.5 seconds pass before the three switches are completed, the registration will be canceled. <Step 7> Press the engine button 26b until the remote control 20 emits the sounds "Do Re Mi." "REC" displayed on the display 24 flashes once, and a signal including the ID is transmitted from the remote control 20. When the junction unit 40 receives the signal including the ID and registers the ID, the junction unit 40 emits "beep, beep, beep" sounds and transmits a response signal to the remote control 20. When the remote control 20 receives the response signal transmitted from the junction unit 40, it emits the receiving sound "Mi Re Do," and the display 24 displays "ok," notifying that remote control registration is complete. Step 8: Remove the key 62 from the keyhole 64.

[0195] (2) Second remote control registration method 9 is an explanatory diagram of the second remote control registration method. The second remote control registration method will be described below with reference to the same figure. <Step 1> to <Step 8> described in the following explanation correspond to <Step 1> to <Step 8> in the same figure, respectively. <Step 1> Disconnect and reconnect the connector 42a from the first connector 42 of the junction unit 40. The junction unit 40 will emit a series of confirmation beeps: "beep beep beep beep beep." <Step 2> Press and hold both the start button 26a and the stop button 26c on the remote control 20 simultaneously for about 5 seconds. <Step 3> Press the stop button 26c until "Rmd" appears on the display 24 of the remote control 20. If no button is pressed for 20 seconds or more, the remote control 20 will emit a beeping buzzer sound, and the registration will be canceled. <Step 4> Press the engine button 26b on the remote control 20. "REC" will appear on the display 24, and the remote control 20 will emit a series of confirmation beeps. If no button is pressed for 20 seconds or more, the remote control 20 will emit a beep beep beep sound, and the registration will be canceled.

[0196] Steps 5 and 6 below are to be performed while the confirmation beeps are being emitted from the remote control 20 (for approximately 40 seconds). If 40 seconds pass before Steps 5 and 6 are completed, the confirmation beeps will disappear and the registration will be canceled. Step 5: Insert the key 62 into the keyhole 64 provided on the vehicle body and operate the key 62 to switch from OFF to ACC to ON. After about three seconds, the junction unit 40 will emit a beep. <Step 6> Press the engine button 26b until the remote control 20 emits the sounds "Do Re Mi." "REC" displayed on the display 24 flashes once, and a signal including the ID is transmitted from the remote control 20. When the junction unit 40 receives the signal including the ID and registers the ID, the junction unit 40 emits "beep, beep, beep" sounds and transmits a response signal to the remote control 20. When the remote control 20 receives the response signal transmitted from the junction unit 40, it emits the receiving sound "Mi Re Do," and the display 24 displays "ok," notifying that remote control registration is complete. Step 8: Operate the key 62 to switch from ON to ACC to OFF, and then remove the key 62 from the keyhole 64.

[0197] 3. Another embodiment of the engine starter 10 is a block diagram showing an outline of another example of the configuration of an engine starter using a system according to the present invention. The figure shows the engine starter 10 being used in an automobile 60 equipped with an immobilizer 66 (start permission device). In the figure, parts having substantially the same configuration as those of the engine starter shown in FIG. 1 are given the same reference numerals. The engine starter 10 of this embodiment can be used in an automobile 60 equipped with an immobilizer 66.

[0198] 3-1. Overall structure The automobile 60 is provided with an engine 70 (drive unit), a vehicle control device 68, an immobilizer 66, and a junction unit 40, and the vehicle control device 68, the immobilizer 66, and the junction unit 40 are connected to one another by a cable 36. The remote control 20 and the genuine key 62a (password code transmitter) are carried by the user. In FIG. 10, the dashed lines indicate connections via wireless communication (the same applies to FIGS. 11 and 12, which will be described later).

[0199] The vehicle control device 68 starts the engine 70 based on a vehicle start signal. The vehicle start signal is transmitted from the remote control 20 when the user operates the remote control 20 to start the engine, and the junction unit 40 receives the vehicle start signal and transmits it to the vehicle control device 68. The vehicle start signal is also transmitted to the vehicle control device 68 by pressing a start button (not shown) provided on the automobile 60, or by inserting and turning the genuine key 62a into the keyhole. The genuine key 62a is provided with the automobile at the time of sale, and transmits a pin code.

[0200] When the immobilizer 66 receives the personal identification code transmitted from the genuine key 62a, it compares this personal identification code with a reference code stored in a memory device provided in the immobilizer 66, and if they match, it transmits a start permission signal to the vehicle control device 68 to permit starting of the engine 70. When the vehicle control device 68 receives the vehicle start signal, it checks for the presence of the start permission signal for 20 ms, and if it confirms that the start permission signal is present during that time, it can start the engine 70.

[0201] In the engine starter 10 of this embodiment, the remote control 20 and the junction unit 40 are both equipped with the communication chip "SX1272," so that the LoRa method, which is one of the spread spectrum methods, and the FSK method, which is a communication method other than the spread spectrum method, can be selected for wireless communication between the remote control 20 and the junction unit 40. When used in a car 60 equipped with an immobilizer 66 and the user carries the original key 62a, the wireless communication method is the FSK method.

[0202] The remote control 20 can receive a personal identification code from the genuine key 62a, convert the received personal identification code into another code (hereinafter referred to as a "conversion code"), and transmit this conversion code to the junction unit 40. Hereinafter, "relaying a personal identification code" refers to "converting the personal identification code transmitted from the genuine key 62a into a conversion code by the remote control 20 and transmitting it to the junction unit 40, and then converting the conversion code back to the original personal identification code by the junction unit 40 and transmitting it to the immobilizer 66." In addition, the remote control 20 transmits a start instruction signal to the junction unit 40 when the user operates to start the engine.

[0203] When the junction unit 40 receives the conversion code from the remote control 20, it converts the conversion code into the original personal identification code and wirelessly transmits the converted personal identification code to the immobilizer 66. When the junction unit 40 receives a start instruction signal from the remote control 20, it transmits a vehicle start signal to the vehicle control device 68 via the cable 36. Note that the communication distance between the genuine key 62a and the immobilizer 66 or the remote control 20 is shorter than the communication distance between the remote control 20 and the junction unit 40.

[0204] 3-2.Operation When a user performs an engine start operation using the remote control 20 , a signal including the conversion code and a start instruction signal are transmitted from the remote control 20 to the junction unit 40 .

[0205] The junction unit 40 receives the signal including the conversion code and the start instruction signal, and transmits the secret code to the immobilizer 66 and also transmits a vehicle start signal to the vehicle control device 68 .

[0206] When the immobilizer 66 receives the personal identification code, it compares the personal identification code with a reference code stored in a memory device provided in the immobilizer 66, and if they match, it sends a start permission signal to the vehicle control device 68 to permit the engine 70 to start.

[0207] If the vehicle control device 68 confirms the presence of a start permission signal within 20 ms of receiving the vehicle start signal, it starts the engine 70. Because the presence of the start permission signal must be confirmed within 20 ms of receiving the vehicle start signal, the FSK method is selected, which has faster communication and response speeds than the LoRa method. However, the distance over which remote control by the remote control unit 20 is possible is shorter than with the LoRa method.

[0208] 3-3. Other uses (1) When using a genuine key in a car equipped with an immobilizer The engine starter of this embodiment can be used in a vehicle equipped with an immobilizer even when the original key is placed inside the vehicle.

[0209] 11 is a block diagram showing an outline of another example of the configuration of an engine starter using the system according to the present invention, showing the case where a genuine key is placed inside a vehicle equipped with an immobilizer. In this case, the LoRa system is used for wireless communication between the remote control 20 and the junction unit 40.

[0210] In this case, since the genuine key 62a is placed inside the automobile 60, the immobilizer 66 can constantly receive the pin code transmitted from the genuine key 62a, and can also constantly send a start permission signal to the vehicle control device 68. In this case, the "relay pin code" function is not used, so the function is turned off and the "non-relay mode" is selected.

[0211] When the user performs an engine start operation, a start instruction signal is transmitted from the remote control 20, and the junction unit 40, upon receiving this start instruction signal, transmits a vehicle start signal to the vehicle control device 68. If the vehicle control device 68 receives a start permission signal within 20 ms after receiving the vehicle start signal, it starts the engine 70.

[0212] The communication method is selected from either the LoRa method or the FSK method, whichever is available. The presence of the start permission signal must be confirmed within 20 ms of receiving the vehicle start signal, but since the start permission signal is transmitted from the original key 62a placed inside the vehicle 60, either method can be selected. If priority is given to the distance over which remote control is possible using the remote control 20, the packet mode of the LoRa method should be selected (long-distance mode). If priority is given to communication speed and response speed, the packet mode of the LoRa method should be selected, with a setting that increases the transmission bit rate compared to the long-distance mode (short-distance mode).

[0213] (2) When used in a vehicle without an immobilizer The engine starter of this embodiment can also be used in automobiles that do not have an immobilizer.

[0214] 12 is a block diagram showing an outline of another example of the configuration of an engine starter using the system according to the present invention, showing the case where the system is used in a vehicle without an immobilizer. In this case, the wireless communication between the remote control 20 and the junction unit 40 uses the LoRa system.

[0215] In this case, since there is no immobilizer, when the user performs an engine start operation, a start instruction signal is transmitted from the remote control 20, and the junction unit 40, upon receiving this start instruction signal, transmits a vehicle start signal to the vehicle control device 68. When the vehicle control device 68 receives a start permission signal, it starts the engine 70. In this case as well, the "relay the personal identification code" function is not used, so this function is turned off.

[0216] The communication method can be selected from either the LoRa method or the FSK method, whichever is available. If priority is given to communication speed and response speed, the FSK method should be selected, and if priority is given to the distance over which remote control by the remote control 20 can be achieved, the LoRa method should be selected.

[0217] 4. Modifications of the system according to the present invention In the engine starter using the system according to the present invention, the above-described two embodiments may be modified as follows.

[0218] In the engine starter according to the above-described embodiment, the strength of the signal transmitted from at least one of the remote control 20 and the junction unit 40 may be set to be equal to or lower than the noise floor.

[0219] The antenna used for wireless communication with the junction unit 40 included in the remote control 20 may be a built-in antenna disposed inside the case 22, in addition to the rod-type antenna 28 shown in FIG.

[0220] The remote control 20 or the junction unit 40 may be configured so that the user can directly or indirectly change at least one of the magnitude of the signal transmission power and the signal bit rate.

[0221] The engine starter according to the above embodiment may be configured to reduce the transmission power when the signal strength received in the last communication between the remote control 20 and the junction unit 40 is -80 dBm or greater and the transmission is made within one minute of the reception of the signal in the last communication, and to maintain the transmission power at least at the transmission power level of the last communication when the signal strength is less than -80 dBm or the transmission is made one minute after the reception of the signal in the last communication.

[0222] Furthermore, the engine starter according to the above embodiment may be configured to increase the transmission bit rate for transmitting the signal when the signal strength received in the last communication between the remote control 20 and the junction unit 40 is -80 dBm or greater and the signal is transmitted within one minute of receiving the signal in the last communication, and to maintain the transmission bit rate at least at the transmission bit rate of the last communication when the signal strength is less than -80 dBm or the signal is transmitted one minute after receiving the signal in the last communication.

[0223] The engine starter according to the above-described embodiment may be configured such that a plurality of spreading factors can be set in the spread spectrum wireless communication, and the spreading factor is changed for each packet transmission.

[0224] The engine starter according to the above embodiment may be configured to be able to perform communication while switching the channel used for communication.

[0225] The engine starter according to the above embodiment may be configured to automatically switch to a channel for which no signal is confirmed by a busy determination. The busy determination of a channel is performed by the control unit 32 of the remote control 20 and the control unit 52 of the junction unit 40, the level determination of a spread spectrum signal is performed using the CAD function, and the level determination of signals using modulation methods other than spread spectrum is performed using RSSI. A busy determination is made when the spread spectrum signal is -130 dBm or higher, and when the other modulation methods are -80 dBm or higher.

[0226] 1, the system described above includes a remote control 20 (first device) and a junction unit 40 (second device) that are capable of wireless communication, the wireless communication between the remote control 20 and the junction unit 40 is performed using a spread spectrum method, the remote control 20 is portable by the user, and the signals transmitted by the remote control 20 include signals that activate the functions of the junction unit 40. The function of the junction unit 40 is, for example, to transmit a vehicle start signal to the vehicle control device 68.

[0227] In this way, users can operate the functions of devices by remote control using wireless communication over a significantly longer distance than conventional FSK methods other than the spread spectrum method (frequency spread method), which is far superior to the comparisons made between the various companies. According to the results of experiments conducted by the inventors, it was possible to operate the functions of devices over a distance roughly twice as long as conventional methods. For example, if the distance at which wireless communication was reliably possible with the conventional FSK method was 1 km, the spread spectrum method enabled communication over a distance of more than 2 km, more than double that distance.

[0228] At least one of the first device and the second device portable by the user may be any device, for example, a golf navigation system, and preferably a handheld device or a remote control. In the above-described embodiment, a remote control 20 is used. For example, a signal transmitted from the remote control may include a signal for activating a function of the other device. At least one of the first device and the second device portable by the user may be particularly equipped with a function for inputting instructions from a user and may be configured to transmit a signal for activating a function of the other device based on the input instruction. The function for inputting instructions from the user may be any device capable of inputting instructions, but may be a sensor capable of detecting user movement, etc., and may particularly be equipped with a means for inputting user instructions. At least one of the first device and the second device portable by the user may be a wearable terminal that can be attached to the body. Preferably, at least one of the first device and the second device portable by the user is a device that can be held in the hand and may be equipped with a function for inputting instructions by hand. Preferably, it is equipped with a means for inputting instructions by pressing with the fingers of the hand. More preferably, the means for inputting instructions is a switch.

[0229] The other of the first device and the second device may be any device, for example, a device that can be carried by the user, preferably a device that cannot be carried by the user, for example, a device fixed to an object, and more preferably a device installed indoors. When fixed to an object, it may be fixed to the ground, for example, and preferably fixed to a gas, electricity, or water meter, etc. When fixed to the ground, it may be a water sprinkler, for example. When fixed to a gas, electricity, or water meter, it may be a terminal device that transmits meter reading data to a remote control. When installed indoors, it may be installed in a golf clubhouse, an automobile, etc. When installed in a clubhouse, it may be installed as a digital signage, for example. When installed in an automobile, it may be installed as an on-board device, for example. In the above-described embodiment, the junction unit 40 is installed in an automobile.

[0230] The system of the present invention may be any system, but may be, for example, a system used in consumer devices or various industrial devices, and particularly a system used in automobile-related devices such as the engine starter described above, allowing a user to appropriately remotely control various devices.

[0231] For example, a system for use with consumer devices may be a system in which one of the first device or the second device that can be carried by the user is a remote control, and the other is a device fixed to the ground, and the signal transmitted from the remote control includes a signal that activates a function of the device.

[0232] In a system for use with consumer devices, it is desirable that one of the first device or the second device, which can be carried by the user, is a portable device, and the other is a transmitter fixed to a gas, electricity, water meter, etc. The signal transmitted from the transmitter to the portable device should include meter reading data and a signal that causes the portable device to compile the meter reading data (a signal that activates a function of the portable device).

[0233] In particular, a wireless communication system using a standard called "Wi-SUN (Wireless Smart Utility Network)" is preferable, which includes a terminal device fixed to a gas, electricity, or water meter, and collects meter reading data using a portable device or the like via wireless communication. Using the system of the present invention with Wi-SUN allows users to collect meter reading data from more remote locations than ever before, minimizing the travel effort required for data collection. For example, when reading an electricity meter in a mountainous area far from roads accessible by car and accessible only by foot, a meter reader carrying a portable device is more likely to be able to collect meter reading data (hereinafter also referred to as "meter information") within the range accessible by car, thereby increasing the possibility of shortening the travel distance even if walking is required after traveling by car. In particular, the portable device should be portable and portable, allowing the user to move around on foot and input instructions manually.

[0234] More preferably, this system would have the first device be a golf navigation system and the second device be a digital signage system installed in the clubhouse. In particular, the signal transmitted from the golf navigation system would include a signal that activates the display and tallying functions of the digital signage. In this case, it would be possible to display the rankings of players entered into the golf navigation system during a round on the digital signage, thereby saving the user the trouble of tallying up player results.

[0235] A system used in an automobile-related device may be, for example, a system used for an automobile engine starter or car security system, in which the first device is a remote control and the second device is an in-vehicle device. In the above-described embodiment, the system is an automobile engine starter. In particular, the signal transmitted from the remote control may include a signal that activates a function of the in-vehicle device, and the signal transmitted from the in-vehicle device may include a signal that activates a function of the remote control. Preferably, the signal transmitted from the remote control is configured to be transmitted based on a user instruction.

[0236] With conventional engine starters and car security systems, for example, in large apartment buildings, parking lots could be located far from the user's room, making them inaccessible. This problem was particularly pronounced in tower apartments. Furthermore, for example, concrete walls could block radio waves, making it impossible to use the system without going out onto a balcony. However, even in such cases, the present invention allows the user to more reliably activate the functions of the other device than before. For example, the engine starter and car security functions can be more reliably activated than before. Therefore, for example, even in cases where the user previously had to move to a location, such as a window or balcony, where radio waves could reach the vehicle in the parking lot more easily, the user is now more likely to be able to activate the engine starter or car security system by operating it from a location indoors, such as next to the bed.

[0237] Furthermore, for example, a system for automobile-related devices equipped with the above-mentioned remote control (portable device) and in-vehicle device can be combined with a wireless communication system that collects Wi-SUN meter information, etc., so that the in-vehicle device acts as a gateway (a gateway) to transmit meter information generated in the home to the portable device. Specifically, for example, the in-vehicle device can receive information such as gas, electricity, and water meter reading data and power generation data from a solar or other power generation device installed in the home from a Wi-SUN device in Wi-SUN mode (a modulation method other than spread spectrum), and the in-vehicle device can then transfer this received information to the portable device (remote control) carried by the user in spread spectrum mode. In this way, users can receive information such as meter reading data within a cycling range, which is wider than the conventional walking range. For example, under conditions where radio waves only reach about 1 km in conventional Wi-SUN mode (a modulation method other than spread spectrum), a range of 6 km can be achieved by lowering the bit rate using spread spectrum. A 1km radius around a house is considered a daily living area (walking distance), while a 6km radius is considered a local living area. Also, most people can get around their home within this local living area (biking distance).

[0238] Preferably, the first device is fixed to an object, and the second device is portable by the user. The user carrying the second device can activate the functions of the first device at the location of the object where the first device is fixed, without using the second device. The second device is carried by the user and moves along with the user's walking or cycling from the location of the object where the first device is fixed as a base point (e.g., the starting point of the movement). The second device returns to the base point (e.g., the original starting point as the end point after traveling to a predetermined destination) when the user moves to the location of the object where the first device is fixed. The "walking or cycling" distance should be a line-of-sight distance of 5 km to 20 km. For example, the base point may be a home, and the user may be an elderly person with dementia. Alternatively, the base point may be a car, and the user may walk from the car, shop at a shopping center, start the engine, and return to the car. Alternatively, the base point may be the car, and the user may walk from the car to their home after returning home, and the next morning start the car engine from inside the home before returning to the car. Alternatively, the base point may be the clubhouse, and the user may walk or move around the golf course while playing, and return to the clubhouse after playing.

[0239] Alternatively, for example, the first device may be a single base unit installed in a nursing facility, and the second device may be a set of slave units carried by multiple residents of the nursing facility. Each slave unit is assigned a different ID, and the base unit stores the correspondence between the ID and the name of the person carrying the slave unit. Each slave unit transmits radio waves containing the ID using a spread spectrum method at regular intervals (e.g., every minute). The base unit checks the ID and RSSI (Received Signal Strength Indicator) of the received radio waves, and when the RSSI of the received radio waves falls below a set value, displays on the base unit the approximate distance from the base unit to the slave unit that transmitted the radio waves and the name of the person associated with the ID. The "RSSI setting value" may be set by previously determining the relationship between the distance between the base unit and the slave unit and the RSSI value and storing it in the base unit, so that the distance can be entered and set in the base unit. Alternatively, "when the RSSI falls below a set value" may be when the RSSI level reaches that equivalent to that outside the care facility, based on the difference in RSSI measured in advance between inside and outside the facility and set in advance.

[0240] The base unit may have a function for selecting a person's name stored in advance from a list or the like, and a function for wirelessly transmitting a signal requesting a response to a slave unit with an ID corresponding to that person's name. If the received ID is its own ID and a response is requested from the base unit, the slave unit wirelessly transmits its own ID and level information regarding the received electric field strength. The base unit determines and displays the position of the slave unit (e.g., distance from the base unit) from the level of electric field strength of the received ID.

[0241] Furthermore, it is preferable that the sub-units have a function for relaying wireless signals inquiring from the base unit between them. For example, the base unit may have a "normal search button (search without relay)" and a "search with relay" button. When the "normal search button" is pressed, it requests responses from all sub-units within the range of the base unit's radio waves, including their IDs and field strength levels. On the other hand, when the "search with relay" button is pressed, it requests responses from all sub-units within the range of the base unit's radio waves and from all sub-units within the range of the radio waves from those sub-units. The responses (e.g., the IDs and field strength levels of other sub-units) are relayed by the sub-units between the base unit and other sub-units. It is also possible to have further relaying between sub-units, and it is preferable to limit the number of relays between sub-units. Furthermore, the base unit and sub-units may each be equipped with a location detector such as a GPS, so that only sub-units within a range specified by the base unit from the location of the base unit are relayed.

[0242] In a "spread spectrum" communication, for example, a narrowband signal modulated to be transmitted is spread to a wideband signal using a predetermined spreading method to reduce the power density, and then transmitted from the transmitting side. At the receiving side, the received signal is despread to obtain the original narrowband signal with a high power density. Furthermore, the "spread spectrum" is particularly suitable for a configuration in which, even if the spread signal received at the receiving side is a weak signal below the so-called noise floor, the signal is despread to return it to the original narrowband signal with a high power density, and the original narrowband signal is demodulated and reproduced as the signal intended to be transmitted. This configuration makes it possible to receive signals that have attenuated below the noise floor over long distances.

[0243] In communications using the "spread spectrum method," modulation of the spread signal performed on the transmitting side and demodulation of the spread signal performed on the receiving side may be performed using a hardware modulator and demodulator, or may be performed using a software defined radio. In particular, it is preferable to use an IC chip that performs the calculations corresponding to such modulation and demodulation.

[0244] Any communication method may be used as the "spread spectrum method," but it is particularly preferable to use a method that increases communication distance even at the expense of communication speed. For example, a frequency hopping method may be used. It is preferable to use a method other than a direct sequence spread spread method. More preferably, the "spread spectrum method" is a method (hereinafter referred to as a "chirp method") in which a chirp signal is generated by continuously changing the frequency, and a signal based on the data to be transmitted is spread and modulated by this (hereinafter referred to as a "chirp method"). It is particularly preferable to combine the chirp method with other methods. For example, it is preferable to combine the chirp method with at least one of a frequency hopping method and a direct sequence spread spread method. For example, it is most preferable to use the LoRa method, which will be described in detail later, as the "spread spectrum method." Conversely, conventional modulation methods other than the spread spectrum method include, in addition to the above-mentioned FSK method, OOK (On-Off Keying), GFSK (Frequency Shift Keying), MSK (Minimum Shift Keying), GMSK (Gaussian Minimum Shift Keying), etc. (hereinafter, these modulation methods will be collectively referred to as "FSK, etc.").

[0245] Furthermore, the "first device and / or second device" that is "portable by the user" may be any device, but may be, for example, a mobile communication device, a mobile information device, a wearable terminal, etc. Furthermore, the "first device and / or second device" that is "portable by the user" may be, for example, a non-dedicated device that can perform functions other than remote control, but may particularly be a dedicated device for remote control, such as a remote control.

[0246] Furthermore, the "signal transmitted by the one device" may be configured to include a signal that activates a function of the other of the first device or the second device. For example, in the case of an engine starter or car security, the signal may be configured to include a signal for starting, stopping, or changing settings of these devices. For example, in the case of an engine starter or car security, the signal may be configured to include a signal for activating an alarm function from these devices to a portable device or remote control. Preferably, the "signal transmitted by the one device" may be configured to include a signal other than a signal that activates a function of the other device. For example, in the case of a car security, the "signal other than a signal that activates a function of the other device" may be data detected by a sensor installed in the vehicle, such as the degree of impact applied to the vehicle. In this embodiment, the signal is the current cabin temperature of the engine starter.

[0247] Furthermore, the "signal transmitted by the one device" may be configured to include a start signal, a stop signal, etc. for consumer devices such as water sprinklers or various industrial devices. Furthermore, the "signal transmitted by the one device" may be configured to include a signal such as player performance information entered into a golf navigation system, etc. Furthermore, when the system of the present invention is used in devices such as gas, electricity, or water meters that use standards such as Wi-SUN, the "signal transmitted by the one device" may be configured to include various data such as meter reading data.

[0248] For example, if the first device is a portable device such as a remote control and the second device is an in-vehicle device, the portable device may be configured to operate in single receive mode and the in-vehicle device may be configured to operate in continuous receive mode. This configuration can extend the battery life of the portable device and more reliably capture signals transmitted from the portable device. In this configuration, it is desirable for the in-vehicle device to transmit the same information multiple times. This configuration can reduce the occurrence of missed reads due to external disturbances in the portable device. It is even more desirable for the in-vehicle device to have a function for transmitting a signal to switch to continuous receive mode from the in-vehicle device to the portable device, and for the portable device to operate in continuous receive mode when it receives this signal. In this configuration, it is particularly desirable to configure the device to operate in continuous receive mode for a fixed period of time. This communication mode can be implemented, for example, by using the SX1272 communication chip.

[0249] "Single receive mode" is, for example, a mode in which only one packet is received within a set time, and in particular, when communicating at a fixed receive timing, it is recommended to configure the receiver circuit to be turned on only at the required receive timing. This makes it possible to reduce power consumption during standby for reception. "Continuous receive mode" is, for example, a mode in which signals are received continuously.

[0250] In this embodiment, the spread spectrum wireless communication between the remote control 20 and the junction unit 40 is performed using the LoRa system.

[0251] Therefore, users can break away from the current situation where the distance at which remote control is possible is roughly uniform.

[0252] A wireless system using a spread spectrum method, particularly the LoRa method (hereinafter also referred to as a "LoRa wireless system"), when designed for the same communication distance as an FSK method, can communicate at a higher transmission bit rate (hereinafter simply referred to as "bit rate", "data rate" or "transmission speed"). A higher bit rate shortens communication time, so the user can obtain a system that allows them to quickly activate one of the functions of the remote control 20 and the junction unit 40 when transmitting a signal to activate the other function from either the remote control 20 or the junction unit 40.

[0253] In this embodiment, the remote control 20 has a function for inputting instructions from the user, and is configured to transmit a signal that activates the function of the junction unit 40 based on the input instruction. This provides a system that quickly responds to the input operation of instructions.

[0254] It is desirable to set the bit rate low in the LoRa system. In this way, higher sensitivity can be obtained. It is most desirable to set the bit rate as low as possible. In particular, it is desirable to set the bit rate as low as possible in the remote control 20 that is portable by the user. In this way, the user can transmit a signal to activate a function of the junction unit 40 from the remote control 20 from a longer distance than before, and activate the function in the junction unit 40. It is also desirable to set the bit rate of the remote control 20 lower than the bit rate of the junction unit 40, for example.

[0255] It is desirable to set the bit rate low in a system that transmits and receives a small amount of digital information, and it is even more desirable to set the bit rate low when transmitting digital information such as for car security or the engine starter of this embodiment.

[0256] In this embodiment, LoRa wireless communication is performed using the communication chip "SX1272" manufactured by SEMTECH, Inc. This communication chip performs the modulation and demodulation of the above-mentioned signals through arithmetic processing.

[0257] In this embodiment, wireless communication between the remote control 20 and the junction unit 40 uses the sub-gigahertz band, and uses channels in the sub-gigahertz band whose bandwidth is wider than the bandwidth of channels in frequency bands below the sub-gigahertz band.

[0258] This allows a user to operate the functions of a device by remote control using wireless communication, using a smaller device than before and over a longer distance than before. While radio waves generally have a shorter propagation distance in the sub-gigahertz band than in frequency bands below the sub-gigahertz band, this problem of short propagation distance can be solved by using a channel in the sub-gigahertz band whose bandwidth is wider than that of a channel in the frequency band below the sub-gigahertz band. In this embodiment, a channel in the sub-gigahertz band whose bandwidth is wider than that of a channel in the frequency band below the sub-gigahertz band is set.

[0259] In this embodiment, the sub-gigahertz band is used as the frequency of the oscillators for wireless communication provided in the remote control 20 and the junction unit 40, and a channel of the sub-gigahertz band frequency is used, the bandwidth of the channel being used being wider than the bandwidth of a channel in a frequency band below the sub-gigahertz band. The frequency for wireless communication is set by a control unit 32 provided in the remote control 20 and a control unit 52 provided in the junction unit 40. Furthermore, both the control unit 32 and the control unit 52 include a microcomputer, and write a value corresponding to the frequency to be set into a register of the microcomputer.

[0260] Furthermore, in this embodiment, the wireless communication between the remote control 20 and the junction unit 40 is a specified low-power wireless communication, using the sub-gigahertz band, and the transmittable power used is a sub-gigahertz frequency that is greater than the transmittable power in frequency bands below the sub-gigahertz band.

[0261] In this embodiment, the "frequency bands below the sub-gigahertz band" are the bands 426.0250 to 426.1375 MHz, 426.0375 to 426.1125 MHz, 429.1750 to 429.2375 MHz, 429.2500 to 429.7375 MHz, and 429.8125 to 429.9250 MHz. In each of these bands, the channel bandwidth is 12.5 kHz, and in particular, in the band 426.0375 to 426.1125 MHz, it is 25 kHz. Furthermore, the transmittable power is 1 mW in the bands 426.0250 to 426.1375 MHz and 426.0375 to 426.1125 MHz, and 10 mW in each of the other bands.

[0262] In this embodiment, the "sub-gigahertz band" refers to a band with a center frequency of 916.0 to 928.0 MHz, with a channel bandwidth of 200 kHz. Channels used in the sub-gigahertz band are 200 kHz, which is 16 times the 12.5 kHz bandwidth of channels in the 426.0250 to 426.1375 MHz, 429.1750 to 429.2375 MHz, 429.2500 to 429.7375 MHz, or 429.8125 to 429.9250 MHz bands. The transmittable power is 20 mW. Channels used in the sub-gigahertz band are channels with a transmittable power of 20 mW, which is twice the 10 mW transmittable power in frequency bands below the sub-gigahertz band.

[0263] In the 400 MHz band, which is included in the "sub-gigahertz frequency band," Japanese regulations at the time of filing allocated a bandwidth of 12.5 kHz or 25 kHz per channel. Meanwhile, in the sub-gigahertz band, there is the 920 MHz band, which allocates a bandwidth of 100 kHz or 200 kHz per channel. As such, the 920 MHz band is a particularly good sub-gigahertz band, as it offers a wider bandwidth per channel than the 400 MHz band, which is a sub-gigahertz frequency band. While the 400 MHz band has a narrower bandwidth per channel than the 920 MHz band, its radio waves have the advantage of reaching farther distances and being less directional and more prone to diffraction, making them easier to receive even behind distant obstacles (mountains or buildings).

[0264] In this embodiment, the "channel to be used" is at least one of six channels with center frequencies of 922.4 MHz, 922.6 MHz, 922.8 MHz, 923.0 MHz, 923.2 MHz, and 923.4 MHz (each with a bandwidth of 200 kHz), and some of these channels can be switched. It is preferable to have a configuration in which the channel that is determined to have no signal present as a result of a busy determination can be automatically switched to. Furthermore, these channels may be configured to use a wider bandwidth by combining multiple adjacent channels; for example, it is preferable to combine five adjacent channels of the six channels to use a bandwidth of 1000 kHz.

[0265] In this embodiment, a "channel" is a frequency band allocated for use in communication, and is a frequency band allocated by Japanese laws and regulations.

[0266] When determining whether a channel is busy, the CAD function is used to determine the level of spread spectrum signals, and the RSSI is used to determine the level of signals using modulation methods other than spread spectrum. The CAD function detects the presence of spread spectrum signals at levels so low that they cannot be detected using RSSI. A busy state is determined to be busy when the signal level is -130 dBm or higher for spread spectrum signals, and when the signal level is -80 dBm or higher for signals using other modulation methods. This allows for more accurate channel busy determination, making it possible to operate device functions over long distances by remote control using wireless communication.

[0267] As shown in Table 1 above, in the cases of "RSSI present" and "CAD present," (A) a busy determination is made due to the presence of both a spread spectrum signal and a signal using a modulation method other than spread spectrum, or (B) a busy determination is made due to the presence of a relatively strong spread spectrum signal (-80 dBm or higher). In the case of (A), the transmission of signals using all modulation methods is prohibited, while in the case of (B), the transmission of signals using modulation methods other than spread spectrum is possible. Furthermore, even in the case of (A), a spread spectrum signal with a different bandwidth and spreading rate from the existing spread spectrum signal is possible.

[0268] If "RSSI exists" and "CAD does not exist," the busy state is determined to be due to the presence of a signal using a modulation method other than spread spectrum. Since no spread spectrum signal is present, it is possible to transmit a spread spectrum signal.

[0269] When "RSSI not present" and "CAD present", the busy state is determined to be due to the presence of a spread spectrum signal, and since there are no signals using modulation methods other than spread spectrum, it is possible to transmit signals using modulation methods other than spread spectrum. Furthermore, even if a signal uses spread spectrum, it can be transmitted as long as the bandwidth and spreading rate differ from those of the existing spread spectrum signal.

[0270] In the case of "No RSSI" and "No CAD", there is no Busy judgment, and since there are no signals using the spread spectrum method or signals using modulation methods other than the spread spectrum method, signals using all modulation methods can be transmitted.

[0271] In this embodiment, the strength of the signal transmitted from the remote control 20 or the junction unit 40 is not particularly specified, but it is preferable that it be below the noise floor.

[0272] This significantly reduces the possibility of interference with signals using modulation methods other than spread spectrum, such as FSK. The signal strength can be kept below the noise floor by, for example, reducing the transmission power, or by transmitting the signal at a high spreading factor that keeps the signal strength below the noise floor. While a higher spreading factor slightly reduces the transmission speed of the transmitted signal, it also has the advantage of improving communication sensitivity and extending communication distance. Therefore, this allows users to remotely control the device over longer distances than before. The "noise floor" should be set to -80 dBm.

[0273] In this embodiment, wireless communication between the remote control 20 and the junction unit 40 using the spread spectrum method is such that signals can be transmitted with the same power at one of the quarter portions of the bandwidth from both ends of the bandwidth of the channel being used to the inside of the bandwidth, and at the center of the bandwidth.

[0274] This allows users to operate device functions by remote control using wireless communication over longer distances than before. Such systems, which enable communication at high transmission bit rates with high modulation efficiency, can be implemented using, for example, spread spectrum and LoRa. On the other hand, FSK has low modulation efficiency because the signal transmission power decreases at the high-frequency and low-frequency ends of the bandwidth and the signal extends outside the bandwidth.

[0275] In the spread spectrum wireless communication between the remote control 20 and the junction unit 40, it is desirable that signals can be transmitted at the same power near both ends of the bandwidth of the channel being used, inwardly by one-quarter of the bandwidth, and near the center of the bandwidth. More desirable is that signals can be transmitted at the same power near at least one end and near the center of the bandwidth of the channel being used. Even more desirable is that signals can be transmitted at the same power across the entire bandwidth of the channel being used.

[0276] In particular, it is advisable to configure the power of signals transmitted outside the bandwidth of the channel being used to be less than a specified value. This will ensure that the amount of signal that extends outside the bandwidth is less than the specified value, thereby increasing modulation efficiency. Given the same communication distance in a communication system, the higher the modulation efficiency, the higher the bit rate at which communication is possible.

[0277] In this embodiment, the remote control 20 and junction unit 40 use the "SX1272" communications chip, which does not change power consumption even when the transmission bit rate is changed. Therefore, increasing the transmission bit rate and shortening the communication time reduces the current consumption of the device, thereby reducing power consumption in the system. The remote control 20 uses a battery as its power source, which extends battery life. This allows users to minimize the hassle of battery replacement, etc.

[0278] At least one of the remote control 20 and the junction unit 40 may be a device whose power consumption increases as the transmission bit rate increases. In particular, it is recommended to set the transmission bit rate so that the reduction in transmission power due to the shortened communication time exceeds the increase in power consumption due to the increase in the transmission bit rate. In this way, overall power consumption can be reduced and battery life can be extended.

[0279] In this embodiment, the wireless communication between the remote control 20 and the junction unit 40 may be configured to use a method that allows transmission at the same power at the center of the entire width and at one edge of the periphery, instead of or in addition to the spread spectrum method. In particular, it is desirable to use a method that allows transmission of signals at the same power across the entire bandwidth of the channel being used. Also, for example, the wireless communication between the remote control 20 and the junction unit 40 may use an OFDM modulation method, instead of or in addition to the spread spectrum method. In particular, it is desirable to use Wi-Fi HaLow (IEEE 820.11ah).

[0280] The wireless communication between the remote controller 20 and the junction unit 40 may be configured to use GFSK modulation instead of or in addition to the spread spectrum method. Preferably, the GFSK modulation should be performed at a speed of several hundred bits per second or less. More preferably, Sigfox should be used.

[0281] Furthermore, wireless communication between the remote control 20 and the junction unit 40 may be performed via wireless network communication, but it is preferable to perform one-to-one communication between the remote control 20 and the junction unit 40. The SX1272 communications chip should be configured to use, for example, 0x12 as the SyncWord value, rather than 0x34, which is used in LoRaWAN. Preferably, a value other than 0x34 or 0x12 should be used. This reduces the possibility of interference with commercially available devices that perform LoRaWAN wireless communication.

[0282] In this embodiment, the remote control 20 and the junction unit 40 use an externally exposed antenna 28 or antenna unit 56, but it is particularly preferable that the remote control 20 be provided with a built-in antenna for use in wireless communication.

[0283] This allows the user to use a device with a simple configuration in which the antenna is not exposed to the outside, particularly the highly portable remote control 20. This is because a wireless system using the spread spectrum method can use an antenna with a lower antenna gain when designed for the same communication distance and the same communication bit rate as a wireless system using the FSK method.

[0284] This effect is particularly pronounced in a wireless system using the LoRa method, as in this embodiment. While typical spread spectrum wireless systems (such as WLAN and WCDMA) strive for interference prevention and high bit rates, the LoRa method significantly improves sensitivity by spreading low-bit-rate signals over a wide band using spread spectrum while consuming a large bandwidth. Therefore, by adopting the LoRa communication method, it is possible to further miniaturize the built-in antenna. This allows the user to carry the portable device in their pocket without it getting in the way, resulting in a system that can be used without stress.

[0285] As the LoRa wireless system has high communication sensitivity, it can use a smaller antenna with low gain. Therefore, by adopting the LoRa wireless system, it is possible to use a remote control (portable device) that has a built-in antenna but can achieve the same radio wave range as a remote control using a conventional rod antenna, providing a system with highly portable remote controls (portable devices) for users.

[0286] In this embodiment, the wireless communication between the remote control 20 and the junction unit 40 is based on the LoRa system, using the sub-gigahertz band, and the bandwidth and transmittable power of the channel used are wider than the bandwidth of channels in frequency bands below the sub-gigahertz band and greater than the transmittable power in those bands, and since the channel is a sub-gigahertz band frequency channel, there is a great advantage to having a built-in antenna.

[0287] In this embodiment, the magnitude of the transmission power of the signal may be changed directly or indirectly by the user.

[0288] This allows the user to use the system with the optimal transmission power depending on the environment in which the user uses it. For example, when the distance between the remote control 20 and the junction unit 40 is short and the communication environment is relatively good, the transmission power can be minimized by setting the transmission power low within a range that does not cause problems in signal transmission. In the case of a remote control 20 that uses a battery 34 as its power source, the user can extend the battery life and reduce the frequency of battery replacement, etc. On the other hand, when prioritizing reliable signal transmission between the remote control 20 and the junction unit 40 over minimizing the transmission power, the transmission power can be set higher, taking into account the expected communication distance, etc. This ensures reliable signal transmission, allowing the user to accurately control the device equipped with the system of the present invention.

[0289] Here, a configuration in which "the magnitude of the signal transmission power can be changed directly by the user" may be a configuration in which the magnitude of the transmission power of the remote control 20 or the junction unit 40 is set by inputting a power value, for example. By allowing "the magnitude of the transmission power to be changed directly by the user" in this way, the user can accurately adjust the transmission power to a magnitude that is appropriate for their own usage conditions.

[0290] An example of a configuration that allows the user to indirectly change the magnitude of the signal transmission power is one in which the magnitude of the transmission power of the remote control 20 or the junction unit 40 is set using a relative numerical value or index associated with the power value. Various indexes associated with the power value can be considered, such as "strong," "medium," or "weak," or an index based on the operating mode. In particular, a configuration that allows the user to select between a "long-distance communication mode (normal mode)" and a "long-life mode" that provides a long battery life is particularly desirable. This allows the user to choose whether to prioritize battery life or the distance at which the device's functions can be activated by remote control using wireless communication. By allowing the user to indirectly change the magnitude of the transmission power in this way, the user can intuitively or intuitively adjust the output transmission power to suit their own usage conditions.

[0291] The configuration in which "the user can directly or indirectly change the magnitude of the signal transmission power" may be any configuration, and may be configured to do so via switches (e.g., dip switches) or control devices provided on junction unit 40 that is not portable by the user, and in particular, may be configured to do so via remote control 20 that is portable by the user.

[0292] The magnitude of the signal transmission power may be changed based on the operation of an operation unit provided on, for example, the remote control 20 or another device. The operation unit may be configured, for example, as a slider, or may be configured as a slider displayed on a display screen provided on the remote control 20 or another device.

[0293] Preferably, the remote controller 20 is configured to be selectable between the above-mentioned "long-distance communication mode (normal mode)" and "long-life mode." In this way, the user can extend the battery life by selecting the long-life mode in an area where communication is possible in the long-life mode, and when communication in the long-life mode becomes impossible in an area farther away than the area where communication is possible in the long-life mode, the user can switch to the long-distance communication mode to activate the function of the other device by remote control using wireless communication.

[0294] Furthermore, when setting the operation mode according to the magnitude of the signal transmission power, such as "long distance communication mode (normal mode)" or "long life mode," each mode may be set in multiple stages or continuously according to the magnitude of the transmission power. By adopting these methods, the user can easily and accurately adjust the magnitude of the signal transmission power.

[0295] In this embodiment, the transmission bit rate of the signal may be changed directly or indirectly by the user.

[0296] In this way, by adjusting the transmission bit rate, the user can use the system under conditions that are optimal for the user's environment. For example, by setting a low transmission bit rate, the user can improve communication sensitivity and ensure a wide communication range. On the other hand, by setting a high transmission bit rate, the user can minimize communication time at the expense of communication sensitivity and communication distance, and can operate the device's functions by remote control using wireless communication over long distances with agile communication operations.

[0297] In this embodiment, the remote control 20 and junction unit 40 use the "SX1272" communications chip, which does not change power consumption even when the transmission bit rate is changed. Therefore, increasing the transmission bit rate and shortening the communication time reduces the current consumption of the devices, thereby reducing power consumption in the system, particularly in the device that transmits the signal. The remote control 20 uses a battery as its power source, which extends battery life. This allows users to minimize the hassle of battery replacement, etc.

[0298] At least one of the remote control 20 and the junction unit 40 may be a device whose power consumption increases as the transmission bit rate increases. In particular, it is recommended to set the transmission bit rate so that the reduction in transmission power due to the shortened communication time exceeds the increase in power consumption due to the increase in the transmission bit rate. In this way, overall power consumption can be reduced and battery life can be extended.

[0299] Here, an example of a configuration in which "the user can directly change the transmission bit rate of the signal" is a configuration in which the transmission bit rate of the remote control 20 or the junction unit 40 is set by inputting a bit rate value. By allowing "the user to directly change the magnitude of the transmission bit rate" in this way, the user can accurately adjust the transmission bit rate to suit their own usage conditions.

[0300] An example of a configuration that allows the user to indirectly change the signal transmission bit rate is a configuration in which the transmission bit rate of the remote control 20 or the junction unit 40 is set using a relative numerical value or index associated with the transmission bit rate. Various indexes associated with the transmission bit rate are possible, such as "high," "medium," or "low," or an index based on the operating mode. In particular, it is desirable to allow the user to select between a "normal mode" and a "speed mode" that provides fast communication. This allows the user to select whether to prioritize the distance over which the device's functions can be activated by remote control using wireless communication or the speed of communication. By allowing the user to indirectly change the signal transmission bit rate in this way, the user can intuitively or intuitively adjust the transmission bit rate to a level appropriate for their own usage conditions.

[0301] The configuration in which "the user can directly or indirectly change the transmission bit rate of the signal" may be any configuration, and may be configured to do so via switches (e.g., dip switches) or a control device provided on a junction unit 40 that the user cannot carry, and in particular, may be configured to do so via a remote control 20 that the user can carry.

[0302] Preferably, the remote controller 20 is configured to be selectable between the above-mentioned "normal mode" and "speed mode." In this way, the user can select the speed mode in an area where communication is possible in the speed mode to make communication operations quicker, and when communication in the speed mode becomes impossible in an area farther away than the area where communication is possible in the speed mode, the user can switch to the normal mode to activate the functions of the other device by remote control using wireless communication.

[0303] The transmission bit rate may be changed by operating an operation unit on a remote control or other device, for example. The operation unit may be configured as a slider, or may be configured as a slider displayed on a display screen on the remote control or other device.

[0304] Furthermore, when setting the operating mode according to the magnitude of the transmission bit rate, such as "normal mode" or "speed mode," each mode may be set in multiple stages or continuously according to the magnitude of the transmission bit rate. By adopting these methods, the user can easily and accurately adjust the magnitude of the signal transmission bit rate.

[0305] In this embodiment, in the information regarding the strength of the signal received in the last communication between the remote control 20 and the junction unit 40, if the signal strength is -80 dBm or higher and the transmission is made within one minute of receiving the signal in the last communication, the transmission power is reduced, and if the signal strength is less than -80 dBm or the transmission is made one minute after receiving the signal in the last communication, the transmission power is maintained at least at the transmission power at the time of the last communication.

[0306] This allows the user to optimize transmission power consumption while ensuring reliable signal transmission and reception in the system. For example, if the signal strength received by the device in the last communication is stronger than necessary, the strength of the next signal transmitted can be reduced. Because at least one of the remote control 20 and the junction unit 40 is portable, even if the signal strength received by the device is stronger than necessary, the distance between the remote control 20 and the junction unit 40 may increase over time as the user moves, etc. In this way, when adjusting the transmission power for the next communication based on the signal strength received by the device in the last communication, it is preferable to use time as an index to estimate the change in the distance between the remote control 20 and the junction unit 40 and adjust the transmission power based on this estimation. In this embodiment, the transmission power is reduced not only when the signal strength received in the last communication is -80 dBm or greater, but also when the next signal is transmitted within one minute of receiving the signal in the last communication. Furthermore, this embodiment is configured to maintain at least the transmission power when the signal strength is below a predetermined value or when a predetermined time has elapsed since receiving the signal in the last communication. This allows the user to operate the device's functions remotely over long distances using wireless communication, while reducing transmission power consumption. Also, for remote controller 20 that uses a battery as its power source, the battery life can be extended, eliminating the need for frequent battery replacement.

[0307] Here, the "predetermined time" for reducing the transmission power, specified as "1 minute," may be set based on, for example, when attempting to reduce the transmission power of the next signal to be transmitted below the transmission power at the time of transmitting the signal in the last communication, the distance at which communication is expected to be established between the remote control 20 and the junction unit 40 even if the distance between the remote control 20 and the junction unit 40 increases, and an assumed speed at which the distance between the remote control 20 and the junction unit 40 increases. For example, assuming a case in which the distance between the remote control 20 and the junction unit 40 increases as the user carrying the remote control 20 moves on foot, the "predetermined time" may be set based on the relationship between the average walking speed of an average adult, the distance at which communication is expected to be established between the remote control 20 and the junction unit 40 after the transmission power is reduced, and the length of the communication distance that is expected to be reduced by the reduction in transmission power. In this way, by using time as an indicator to estimate the change in the distance between the remote control 20 and the junction unit 40, setting a "predetermined time" based on this estimated result, and using this predetermined time as one of the criteria for reducing transmission power, even if control is performed to suppress transmission power consumption, the user can operate the functions of the device by remote control using wireless communication over long distances without feeling inconvenienced.

[0308] The "predetermined time" for reducing the transmission power may be constant or may be varied depending on the signal strength.

[0309] Here, in a system that includes a remote control 20 that can be carried by the user and a junction unit 40 that is powered by a battery installed in the vehicle, and in which basic control begins with sending a command from the remote control 20, the transmission power consumption on the junction unit 40 side can be reduced, and the power consumption of the battery installed in the vehicle can be kept to a minimum.

[0310] Furthermore, for example, when the amount of information to be transmitted is large and the information is divided into multiple transmissions, it is preferable to configure the first transmission to be performed with high transmission power and adjust the second and subsequent transmissions based on the radio wave intensity of the first transmission. In this way, the transmission power can be optimized. In this case, the battery life of the remote control 20 can be extended, and the frequency of battery replacement by the user can be minimized.

[0311] Furthermore, for example, in the case of a car security system, when a sensor detects that some kind of trouble has occurred in the car, a signal can be sent from the in-vehicle device, which is a fixed device, to the remote control, even if no command is sent from the remote control. In this way, when a user who has learned that the car security system is activated operates the remote control to disable the car security system, the transmission power of the remote control's transmission signal can be reduced based on the radio wave strength of the signal previously received from the in-vehicle device, minimizing power consumption in the battery built into the remote control and minimizing the frequency with which the user has to replace the battery.

[0312] Furthermore, it is preferable to configure the system so that it can be configured, for example, by sending a signal from the remote control 20 to the junction unit 40. In this way, by sending a setting start command from the remote control 20, the transmission power of the signal transmitted from the remote control 20 can be reduced based on the radio wave strength of the response signal returned from the junction unit 40, thereby minimizing power consumption in the battery 34 built into the remote control 20 and minimizing the frequency with which the user has to replace the battery.

[0313] A user carrying the remote control 20 may move after receiving a signal in the last communication in the system. Therefore, if the transmission power of the remote control 20 or the junction unit 40 is reduced after a predetermined time (one minute in this embodiment) has elapsed, the distance between the remote control 20 and the junction unit 40 may become too great, resulting in insufficient radio wave strength and making it impossible to operate the device's functions remotely via wireless communication over long distances. Therefore, it is preferable to reduce the transmission power within a predetermined time and maintain the transmission power after the predetermined time has elapsed. This allows the device's functions to be operated remotely via wireless communication over long distances and extends battery life. This minimizes the frequency with which the user has to perform tedious tasks such as battery replacement.

[0314] Furthermore, the configuration of "maintaining at least the transmission power" may be a configuration of maintaining the transmission power or a configuration of increasing the transmission power. As in the present embodiment, when the strength of the signal received in the last communication is less than -80 dBm or when one minute has elapsed since the signal was received in the last communication, the transmission power may be maintained at the transmission power level at least at the transmission power level of the last communication. This configuration prevents communication from being terminated due to a reduction in transmission power, thereby ensuring communication stability. This allows the user to operate the device's functions by remote control over long distances using wireless communication without any inconvenience, even when the strength of the signal received in the last communication is weak or a predetermined time has elapsed since the last communication.

[0315] If the "predetermined time" for reducing the transmission power is changed depending on the signal strength, the higher the signal strength, the shorter the predetermined time should be, and the lower the signal strength, the longer the predetermined time should be. However, if the signal strength is below the predetermined value, the transmission power should at least be maintained.

[0316] In the configuration of this embodiment, for example, if communication is not possible with the transmission power reduced, the transmission power is increased, and if communication is still not possible, the transmission power is increased further. When communication is not possible with the transmission power reduced, the transmission power is increased stepwise or continuously, and in particular, it is increased directly to the maximum. This configuration offers the user the advantage of being able to minimize power consumption.

[0317] In the configuration of this embodiment, the transmission power settings of the remote control 20 and the junction unit 40 may be configured to be maximum under normal conditions and then automatically reduced, or may be configured to be performed by the user by operating the remote control 20 or by setting a dip switch provided on the junction unit 40. The display unit 24 of the remote control 20 may also be configured to display the transmission power. In this way, the user can check the transmission power from this display. The display unit 24 of the remote control 20 may also be configured to display the strength of the received radio waves. In this way, the user can use the remote control 20 while checking whether communication is possible based on the displayed radio wave strength.

[0318] In this embodiment, in the information regarding the strength of the signal received in the last communication between the remote control 20 and the junction unit 40, if the signal strength is -80 dBm or higher and the transmission is within one minute of receiving the signal in the last communication, the transmission bit rate for transmitting the signal is increased, and if the signal strength is less than -80 dBm or the transmission is one minute after receiving the signal in the last communication, the transmission bit rate is maintained at least at the transmission bit rate at the time of the last communication.

[0319] This allows the user to optimize the transmission bit rate while ensuring reliable signal transmission and reception in the system. For example, if the signal strength received by the device in the last communication is stronger than necessary, the next transmitted signal strength can be reduced. Because the remote control 20 is portable, even if the signal strength received by the device is stronger than necessary, the distance between the remote control 20 and the junction unit 40 may increase over time as the user moves, for example. To adjust the transmission bit rate for the next communication based on the signal strength received by the device in the last communication, it is preferable to use time as an index to estimate the change in the distance between the remote control 20 and the junction unit 40 and adjust the transmission bit rate based on this estimation. The configuration of this embodiment is configured to increase the transmission bit rate not only when the signal strength received in the last communication is -80 dBm or higher, but also when the next signal is transmitted within one minute of receiving the signal in the last communication. Furthermore, the configuration of this embodiment is configured to maintain at least the transmission bit rate when the signal strength is less than -80 dBm or when transmission is initiated one minute after receiving the signal in the last communication. This allows the user to operate the device's functions remotely over long distances using wireless communication, while reducing transmission power consumption. Also, for remote control 20 that uses battery 34 as its power source, the battery life can be extended, eliminating the need for frequent battery replacement.

[0320] Here, the "predetermined time" specified as "1 minute" for increasing the transmission bit rate may be set based on, for example, the distance at which communication is expected to be established between the remote control 20 and the junction unit 40 even if the distance between the remote control 20 and the junction unit 40 increases, and the assumed speed at which the distance between the remote control 20 and the junction unit 40 increases, when the transmission bit rate of the next signal to be transmitted is increased above the transmission bit rate at which the signal was transmitted in the last communication. If a case is assumed in which the distance between the remote control 20 and the junction unit 40 increases as the user moves on foot, the "predetermined time" may be set based on the relationship between the average walking speed of an average adult, the distance at which communication is expected to be established between the remote control 20 and the junction unit 40 after the increase in the transmission bit rate has been reduced, and the length of the communication distance that is expected to be reduced due to the increase in the transmission bit rate. In this way, by using time as an index to estimate changes in the distance between the remote control 20 and the junction unit 40, setting a "predetermined time" based on this estimated result, and using this predetermined time as one of the criteria for increasing the transmission bit rate, even if control is performed to increase the transmission bit rate, the user can operate the device's functions by remote control using wireless communication over long distances without feeling any inconvenience.

[0321] The "predetermined time" during which the transmission bit rate is increased may be constant or may be varied depending on the signal strength.

[0322] Furthermore, the configuration of "maintaining at least the transmission bit rate" may be a configuration of maintaining the transmission bit rate or a configuration of decreasing the transmission bit rate. As in the present embodiment, when the strength of the signal received in the last communication is less than -80 dBm or when transmission is performed one minute after the reception of the signal in the last communication, the transmission bit rate may be maintained at the transmission bit rate at least at the transmission bit rate at the time of the last communication. This configuration prevents communication from being terminated due to an increase in the transmission bit rate, thereby ensuring communication stability. This allows the user to operate the device's functions by remote control over long distances using wireless communication without any inconvenience, even when the strength of the signal received in the last communication is weak or a predetermined time has passed since the previous communication.

[0323] In a communication system with the same bandwidth, the transmission bit rate, sensitivity (travel distance), and transmission power are inversely proportional to each other. In other words, in the system of the present invention, increasing the transmission bit rate reduces the distance (decreased sensitivity) for the same bandwidth and transmission power. This shortens the distance at which a device's functions can be activated by remote control using wireless communication, but shortens the transmission time and enables faster system communication. Here, if the received signal strength is high, communication is possible even with low sensitivity, so communication is possible even if the transmission bit rate is increased. Therefore, in this embodiment, the stronger the received radio waves, the higher the transmission bit rate is. This allows a user to quickly activate one of the functions from either the remote control 20 or the junction unit 40 when transmitting a signal to activate the other function from the other.

[0324] In this embodiment, in wireless communication using the spread spectrum method, a plurality of spreading factors can be set, and it is preferable to change the spreading factor for each transmission of one packet.

[0325] This allows users to build a wireless system that is extremely difficult to intercept.

[0326] The "changing of the spreading factor" may be configured to be performed in a predetermined pattern. The "predetermined pattern" of the "changing of the spreading factor" may be configured to be random or in a predetermined order. Here, in the system of the present invention, the higher the spreading factor, the longer the distance at which the device's functions can be activated by remote control using wireless communication. Therefore, it is particularly preferable to configure the system to employ the maximum spreading factor and the spreading factor one step lower. In such a configuration, the pattern of the changing of the spreading factor may be configured to alternate between the maximum spreading factor and the spreading factor one step lower in a predetermined pattern. In this way, it becomes possible to activate the device's functions by remote control using wireless communication over a long distance and in a manner that is difficult to intercept.

[0327] In this embodiment, the spreading factor is changed every time one packet is transmitted, but any other configuration is acceptable, such as every time a packet of a predetermined amount of data is transmitted, or every time a predetermined time has elapsed.

[0328] The "spreading factor" may be, for example, the ratio (C / B) of the spreading code rate (also called "chip rate"; C) to the transmission bit rate (B).

[0329] In this embodiment, it is preferable to be able to perform communication while switching the channel used for communication.

[0330] In this way, the frequency band allocated for communication is switched during communication, allowing users to obtain a system that is less susceptible to interference between spread spectrum communication systems. In this case, the receiver and transmitter switch channels in sync. For example, if the band used for wireless communication is the 920 MHz band, it is recommended to use six channels with center frequencies of 922.4 MHz, 922.6 MHz, 922.8 MHz, 923.0 MHz, 923.2 MHz, and 923.4 MHz, which can be switched between. Note that channels other than these may also be used.

[0331] Spread spectrum methods, particularly LoRa methods, allow for significantly longer communication distances than FSK methods. Therefore, when a communication method with a long communication distance, such as LoRa, is adopted, there is a high possibility of interference occurring due to other users' communications interrupting the communication range. Therefore, when using spread spectrum methods, particularly LoRa methods, it is preferable to suppress interference by appropriately switching the channel used for communication. This allows users to communicate stably without being affected by other users' devices using spread spectrum communication methods nearby.

[0332] In this embodiment, the system includes a vehicle control device 68 that starts the engine based on a vehicle start signal, and an immobilizer 66 that can transmit a start permission signal to the vehicle control device 68 to permit the start of the engine 70. The system receives a personal identification code transmitted from a genuine key 62a that is portable by the user and capable of transmitting a personal identification code, and indirectly transmits the personal identification code to the automobile 60 to which the start permission signal is transmitted by the immobilizer 66 based on the received personal identification code and a reference code provided in the immobilizer 66. The wireless communication can be selected between a spread spectrum method and a communication method other than the spread spectrum method, and the remote control 20 that can be carried by the user can receive a secret code from the original key 62a and can transmit a signal including a conversion code converted from the received secret code and a start instruction signal to the junction unit 40, and the junction unit 40 can be mounted on the automobile 60 and can convert the received conversion code into a secret code and transmit the converted secret code to the immobilizer 66, and can transmit a vehicle start signal to the vehicle control device 68 upon receiving a start instruction signal.

[0333] In this way, in an automobile 60 equipped with an immobilizer 66, the user can start the engine 70 using the remote control 20 that the user can carry with them, without leaving the original key 62a inside the vehicle. Generally, due to security concerns, for example, the original key 62a and the immobilizer 66 cannot send and receive a personal identification code unless they are in close proximity, and starting of the engine 70 cannot be permitted. However, in this way, even if the original key 62a and the immobilizer 66 are far apart, the personal identification code sent from the original key 62a is relayed between the remote control 20 that the user can carry and the junction unit 40 installed in the automobile 60, and can be received by the immobilizer 66, allowing starting of the engine 70.

[0334] In this embodiment, the configuration for "indirectly transmitting" the PIN code is such that the remote control 20 receives the PIN code from the genuine key 62a, converts the PIN code into a different conversion code, and transmits it to the junction unit 40, and the junction unit 40 converts the received conversion code back into the original PIN code before transmitting it to the immobilizer 66.

[0335] Regarding the junction unit 40, in this embodiment, the configuration of "mounting it on a vehicle" refers to a configuration in which it is retrofitted to a sold vehicle, but it may also be a configuration in which it is originally attached to the vehicle by the automobile manufacturer when the vehicle is manufactured.

[0336] In this embodiment, the start instruction signal transmitted by the remote controller 20 is issued by operating the operation button 26 by the user.

[0337] In this embodiment, the wireless communication between the remote control 20 and the junction unit 40 can be selected between the LoRa system and the FSK system. Therefore, even if it is difficult to permit starting of the engine 70 using one of the systems, the possibility of permitting starting of the engine 70 can be increased. The "communication system selection" may be configured in any way, for example, via switches (e.g., DIP switches) or a control device provided on the junction unit 40, and particularly preferably via the portable remote control 20. Furthermore, the communication system selection may be configured to be performed based on the operation of an operation unit provided on the remote control 20 or another device. The operation unit may be configured, for example, as a slider, or may be configured as a slider displayed on a display screen provided on the remote control 20 or another device.

[0338] It is preferable to configure the system so that the user can select between a mode in which the pin code transmitted from the genuine key 62a is relayed by the remote control 20 and the junction unit 40 (hereinafter referred to as the "relay mode"), and a mode in which the pin code is not relayed (hereinafter referred to as the "non-relay mode"). In this way, users and retailers can support both vehicle models with an immobilizer 66 and vehicle models without an immobilizer 66 by simply preparing one type of system equipped with the remote control 20 and the junction unit 40, and can also accommodate users of vehicle models equipped with an immobilizer 66 who do not mind leaving the genuine key 26a inside the vehicle 60. The configuration for selecting the "relay mode" or the "non-relay mode" can be configured, for example, by providing a switch on the in-vehicle device and selecting by this switch.

[0339] When "Relay Mode" is selected, it is recommended to configure the wireless communication on the transmitting side to be in FSK continuous mode. "Continuous Mode" is a mode in which the level of the DIO2 / DATA pin is transmitted as is (without going through the FIFO).

[0340] When "non-relay mode" is selected, it is preferable to select "long distance mode" or "short distance mode." In this embodiment, "long distance mode" selects packet mode of LoRa system for wireless communication on the transmitting side. "Packet mode" is SPI (Serial It is recommended to configure the device so that data provided via the Peripheral Interface is sent as packets via FIFO.

[0341] In this embodiment, the "short distance mode" is set so that the wireless communication on the transmitting side uses the LoRa method and has a higher transmission bit rate than the long distance communication mode, but the wireless communication on the transmitting side may also be set to the FSK method packet mode.

[0342] The components of the present embodiment may be arbitrarily combined. Also, the components described in the Summary of the Invention and the components of the present embodiment may be arbitrarily combined. [Explanation of symbols]

[0343] 10 Engine Starter 20 Remote Control 22 cases 24 Display 24a horizontal bar 24b engine start animation 26 Operation buttons 26a Start button 26b Engine button 26c Stop button 28 Antenna 30 Wireless communication circuit 32 Control Unit 34 Battery 36 Cable 40 Junction Unit 42 First Connector 42a plug 44 Second Connector 46 Third Connector 48 Fourth Connector 50 Wireless communication circuit 52 Control section 54 Temperature Sensor 56 Antenna unit 60 Automobiles 62 keys 62a Genuine key 64 Keyhole 66 Immobilizer 68 Vehicle control device 70 Engine

Claims

1. A first device and a second device capable of wireless communication are provided, at least one of the first device and the second device is portable by a user, and the signal transmitted by the one device includes a signal for activating a function of the other of the first device or the second device; reducing transmission power when a strength of a signal received in a last communication between the first device and the second device is equal to or greater than a predetermined value and transmission is performed within a first predetermined time period from reception of the signal in the last communication; A system characterized by maintaining the transmission power at least at the transmission power at the time of the last communication when the signal strength is less than the predetermined value or when transmitting after the first predetermined time has elapsed since receiving the signal in the last communication.

2. 2. The system according to claim 1, further comprising a function for changing the first predetermined time period depending on the signal strength.

3. increasing a transmission bit rate for transmitting a signal when the strength of the signal received in the last communication between the first device and the second device is equal to or greater than a predetermined value and the signal is transmitted within a second predetermined time period from the reception of the signal in the last communication; The system according to claim 1 or 2, characterized in that when the signal strength is less than the predetermined value or when transmission is performed after the second predetermined time has elapsed since reception of the signal in the last communication, the transmission bit rate is maintained at least at the transmission bit rate at the time of the last communication.

4. The first device in the system according to any one of claims 1 to 3.

5. The second device in the system according to any one of claims 1 to 3.

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