OUTPUT CONTROL METHOD OF RADIO COMMUNICATION MODULE, MANUFACTURING METHOD OF RADIO COMMUNICATION MODULE AND OUTPUT CONTROL UNIT OF RADIO COMMUNICATION MODULE

An output control method for adjusting an output of a radio communication module includes a temperature adjustment step, a transmission step, a feedback control step, a measurement step, and an output control step. The temperature adjustment step sets a temperature of the radio communication module to a predetermined set temperature by a temperature adjusting mechanism. The transmission step has a first antenna transmit a radio signal by sending a transmission signal of a predetermined frequency to the radio communication module. The feedback control step controls an output of the transmission signal based on a comparative result between a power value obtained by detecting the transmission signal and a predetermined threshold value of power. The measurement step receives the radio signal by a second antenna, and measures an equivalent isotropic radiated power of the radio signal. The output control step adjusts an output of the transmission signal based on the equivalent isotropic radiated power measured in the measurement step.

FIELD OF THE INVENTION

The present invention relates to an output control method of a radio communication module, a manufacturing method of a radio communication module and an output control unit of a radio communication module.

Priority is claimed on Japanese Patent Application No. 2022-022053, filed Feb. 16, 2022, the contents of which are incorporated herein.

DESCRIPTION OF RELATED ART

In a radio communication module (for example, refer to Patent Literature 1), transmission power may be subject to constraints by legal regulations. For example, the upper strength limit of the Equivalent Isotropic Radiated Power (EIRP) is regulated by the Radio Act. For this reason, a radio communication module where the transmission power does not diverge off from the regulated value is desirable. To stabilize the transmission power, a radio communication module adopts a method of using an Automatic Level Control (ALC) to adjust the transmission power (for example, refer to Patent Literatures 2 and 3).

CITATION LIST

Patent Literature

SUMMARY OF THE INVENTION

Technical Problem

However, in the above-mentioned adjustment method, a deviation between the power detected in a feedback circuit during the automatic level control and the actual transmission power may exist. For this reason, a method where output of a radio communication module is accurately adjusted is desirable.

The object of the present invention is to provide an output control method capable of accurately adjusting an output of a radio communication module, a manufacturing method of a radio communication module, and an output control unit of a radio communication module.

Solution to Problem

A first embodiment of the present invention provides an output control method for adjusting an output of a radio communication module including a first antenna, the method including a temperature adjustment step that sets a temperature of the radio communication module to a predetermined set temperature by a temperature adjusting mechanism that adjusts the temperature of the radio communication module, a transmission step that has the first antenna transmit a radio signal by sending a transmission signal of a predetermined frequency to the radio communication module, a feedback control step that controls an output of the transmission signal based on a comparative result between a power value obtained by detecting the transmission signal and a predetermined threshold value of power, a measurement step that receives the radio signal by a second antenna that is capable of radio communicating with the first antenna, and measures an equivalent isotropic radiated power of the radio signal, and an output control step that adjusts an output of the transmission signal based on the equivalent isotropic radiated power measured in the measurement step.

According to this configuration, since an output (transmission power) of the transmission signal is adjusted based on the equivalent isotropic radiated power of the radio signal transmitted from the radio communication module, it is possible to accurately adjust the output of the transmission signal. As such, even in the case where fluctuations in frequency characteristics of an antenna, characteristic variations for each module or the like occurs, it is possible to avoid having the transmission power exceed a regulated value. Also, it is also possible to suppress a divergence of a transmission power from values determined by product specifications.

Also, in the output control step, the threshold value may be changed based on a judgement result of whether the equivalent isotropic radiated power is within a predetermined range or not.

Also, in the output control method of the radio communication module, gain values may be calculated based on the difference between the power value and the threshold value at each set temperature which varies with one another, and in the output control step, the threshold values may be changed according to a comparative result of the plurality of the gain values.

Also, in the output control method of the radio communication module, at each set temperature which varies with one another, an output of the transmission signal may be adjusted by the temperature adjustment step, the transmission step, the feedback control step, the measurement step and the output control step.

A second aspect of the present invention provides a manufacturing method of a radio communication module that provides a memory unit that records information in the radio communication module, and records an appropriate threshold value at the output control step of the output control method of the radio communication module.

A third aspect of the present invention provides an output control unit for adjusting an output of a radio communication module including a first antenna that includes a temperature adjusting mechanism to adjust a temperature of the radio communication module, a signal setting unit that has the first antenna transmit a radio signal by sending a transmission signal of a predetermined frequency to the radio communication module, an ALC control system that controls an output of the transmission signal based on a comparative result between a power value obtained by detecting the transmission signal and a predetermined threshold value of power, a second antenna that is capable of radio communicating with the first antenna, a measurement unit to measure an equivalent isotropic radiated power of the radio signal received by the second antenna, and an output judgement unit that adjusts an output of the transmission signal based on the equivalent isotropic radiated power measured in the measurement unit.

According to this configuration, since the output of the transmission signal (transmission power) is adjusted based on the equivalent isotropic radiated power of radio signal transmitted from the radio communication module, it is possible to accurately adjust the output of the transmission signal. As such, even in the case where fluctuations in frequency characteristics of an antenna, characteristic variations for each module, or the like occurs, it is possible to avoid having the transmission power exceed a regulated value. Also, it is also possible to suppress a divergence of a transmission power on values determined by product specifications.

Advantageous Effects of Invention

According to the above-mentioned aspect of the present invention, it is possible to accurately adjust an output of a radio communication module.

DETAILED DESCRIPTION OF THE INVENTION

First Embodiment

FIG.1is a diagram of a first embodiment of an output control unit100of a radio communication module. The output control unit of the radio controlled module may simply be referred to as an “output control unit”.FIG.2is a diagram of a portion of a module holding unit10.FIG.3is diagram of a radio communication module1and a temperature adjusting mechanism20.FIG.3is an enlarged view of portion A shown onFIG.2.FIG.4is an exploded view of the radio communication module1and the temperature adjusting mechanism20.

An X direction, a Y direction, and a Z direction are defined as follows. The X direction is a direction where the module holding unit10and a measurement antenna unit60are arranged. The +X direction is a direction from the measurement antenna unit60towards the module holding unit10. The Z direction is an up-down direction. The +Z direction is an upward direction. The Y direction is a direction orthogonal to the X direction and Z direction. As for the module holding unit10, a direction that gets closer to the measurement antenna unit60is referred to as a “front” direction. As for the measurement antenna unit60, a direction that gets closer to the module holding unit10is referred to as a “front” direction. Furthermore, positional relationships decided herein of the orientation of the output control unit100during usage are not limited to the orientation thereof.

As shown inFIG.1andFIG.2, the output control unit100adjusts the output of the radio communication module1. Before explaining the output control unit100, the radio communication module1is explained.

As shown inFIG.4, the radio communication module1includes an antenna base plate2and an RFIC3.

The antenna base plate2includes a rectangular plate substrate4and a first antenna5. The substrate4, for example, is formed of a material having a small dielectric loss tangent (in other words, small losses at high frequency signals), and good transmission properties of high frequency signals. The first antenna5is formed on a first surface4a(a surface in the −X direction), which is one of the surfaces of the substrate4, or on an inner part of the substrate4.

The first antenna5is not particularly limited. For example, the antenna pattern5may be an array antenna or a phased array antenna which a plurality of radiating elements (not shown in figures) are formed in a two-dimensional shape on the first surface4a. The first antenna5for example, may be any antenna which may include a linearly shaped antenna, a flat surface antenna, a microstrip antenna, a patch antenna and so on.

The RFIC3includes a high frequency signal processing integrated circuit (RFIC: Radio Frequency Integrated Circuit) for millimeter wave bands and the like. An example of an IC package that is applicable to the RFIC3, may be for example, a BGA (Ball Grid Alley), a CSP (Chip Size Package), or an FOWLP (Fan Out Wafer Level Package) and so on. The RFIC3is implemented on a second surface4b(a surface in the +X direction) of the surface on the other side of the antenna base plate2. The RFIC3, for example, may be implemented by a connection part which is formed by soldering (SnAgCu or the like) or the like on the second surface4bof the antenna base plate2. The RFIC3may include a memory unit6such as a memory or the like (refer toFIG.4). The memory unit6is capable of recording data.

The RFIC3for example, is made out to be a rectangular plate. A dimension of the Y direction of the RFIC3is less than a dimension of the Y direction of the antenna base plate2. A dimension in the Z direction of the RFIC3is less than a dimension in the Z direction of the antenna base plate2.

The radio communication module1for example, conducts high frequency signal transmission and reception of millimeter wave bands and the like. Although it is preferable that the radio communication module1be able to transmit and receive high frequency signals, the radio communication module1may be a radio communication module that conducts transmission only. For frequencies of high frequency signals, for example, 10 GHz to 300 GHz, or 60 GHz to 80 GHz and so on may be mentioned.

[Output Control Unit of Radio Communication Module]

As shown onFIG.1, the output control unit100includes the module holding unit10, the temperature adjusting mechanism20, a housing case30, a gas supplier40, a motion mechanism50, the measurement antenna unit60, and a chamber90.

The module holding unit10includes a base11, a back plate12, a support plate13, a plurality of support columns14(refer toFIG.2), and a holding plate15.

The back plate12extends upwards from the upper part of base11. The support plate13overlaps with the front surface (the surface in the −X direction) of the back plate12. In the embodiment, the back plate12and the support plate13are disposed to be vertical in the X direction.

As shown onFIG.2, the support column14extends to the front side (the —X direction) from the front surface (the surface in the −X direction) of the support plate13. The support column14as seen from the front, is provided on each of the four ends of the holding plate15. A receiving hole is formed on a tip surface of the support column14(not shown in figures).

The holding plate15functions as a holder holding the radio communication module1. The holding plate15, for example, is made of a non-metallic material (resin, glass or the like) that is minimally affected by the radio waves transmitted and received by the radio communication module1. It is preferable that the holding plate15be made of a resin. The holding plate15may be formed from a fiber reinforced resin. The holding plate15may be made from a dielectric material.

The holding plate15for example, may be a rectangular plate. A single or a plurality of through openings16may be formed on the holding plate15. The through openings16are formed so as to penetrate the holding plate15from one side of the surface of the holding plate15to the other side of the surface. The through openings16, as seen from a thickness direction of the holding plate15, are large enough to include the first antenna5of the radio communication module1.

As shown onFIG.2, the holding plate15is fixed on the tip surface of the support column14by a fixture17. Insertion through holes (not shown in figures) are formed on the four ends of the holding plate15. The fixture17is inserted through the insertion through hole on the holding plate15, which is inserted into the receiving hole on the support column14. The fixture17is fixed to the receiving hole using screws and the like. From this, the holding plate15holds down the radio communication module1towards a heat spreader22(refer toFIG.3).

It is possible for the module holding unit10to pivot around a rotation axis along the Z direction. From this, the module holding unit10may be set to face the measurement antenna unit60in any direction. In the embodiment, the module holding unit10faces the measurement antenna unit60directly. However, because it is possible for the module holding unit10to pivot around the pivot axis, it is possible to change the direction that the module holding unit10faces in the left-right direction.

As shown onFIG.3andFIG.4, the temperature adjusting mechanism20adjusts the temperature of the radio communication module1.

The temperature adjusting mechanism20includes a temperature regulator21, the heat spreader22, a temperature adjusting sensor23, a heat transfer sheet24, a temperature monitoring sensor25, a heat sink26, a power source27, a temperature control unit28, and a dew point meter29(refer toFIG.2).

The temperature regulator21, for example, is a rectangular plate. The temperature regulator21overlaps the front surface (surface in the −X direction) of the heat sink26. The temperature regulator21, for example, is a Peltier element. When current flows in the first direction through the Peltier element due to electrification, the temperature of a surface of one side of the Peltier element increases, while the temperature of the surface on the other side decreases. When current flows in the second direction (opposing direction to that of the first direction) through the Peltier element, the temperature of a surface of one side of the Peltier element decreases, while the temperature of the surface on the other side increases. The temperature of the surface of one side of the Peltier element and temperature of the surface of other side is determined by the magnitude of the current that flows through the Peltier element. In the case where the temperature regulator21is the Peltier element, by controlling the current that flows through the temperature regulator21, it is possible to adjust the temperature of the radio communication module1.

The temperature regulator21contacts the RFIC3of the radio communication module1through the heat spreader22and the heat transfer sheet24. It can be said that that temperature regulator21is in indirect contact with the RFIC3of the radio communication module1. Since the heat spreader22and the heat transfer sheet24are provided in between the temperature regulator21and the radio communication module1, the temperature regulator21is in contact with the RFIC3of the radio communication module1so as to be capable of transferring heat.

Also, in the embodiment, although the temperature regulator21is in indirect contact with the RFIC3of the radio communication module1so as to be capable of transferring heat, the temperature regulator21may be in direct contact with the RFIC3of the radio communication module1so as to be capable of transferring heat. In other words, the temperature regulator21may be in direct contact with the RFIC3of the radio communication module1without having the heat spreader22and the heat transfer sheet24interpose therebetween. In this manner, the temperature regulator21is in direct or in indirect contact with the RFIC3of the radio communication module1and is capable of transferring heat.

As shown inFIG.4, the heat spreader22is able to disperse the heat from the temperature regulator21. The heat spreader22is a multilayered structure (double-layered to be precise) which includes a first part22A and a second part22B. The first part22A and the second part22B are formed of a material with a high thermal conductivity, for example, metals such as copper or aluminum, carbon materials, or the like.

The first part22A for example, may be a rectangular plate. The first part22A overlaps the front surface (surface in the −X direction) of the temperature regulator21. The first part22A, as seen from a thickness direction, is large enough to include the temperature regulator21. The first portion22A faces the temperature regulator21.

The second part22B overlaps the front surface (surface in the −X direction) of the first part22A. The second part22B, for example, may be a rectangular plate. The second part22B, as seen from a thickness direction, is large enough to include the RFIC3of the radio communication module1. The second part22B faces the radio communication module1.

Between the rear surface of the second part22B and the front surface of the first part22A, a stress relief layer22C is formed. The stress relief layer22C, for example, may be made from a thermal grease. The second part22B is in surface contact with the front surface of the first part22A through the stress relief layer22C.

The temperature adjusting sensor23(temperature sensor) detects the temperature of the heat spreader22. The temperature adjusting sensor23, for example, may be built-into the first part22A of the heat spreader22. The temperature adjusting sensor23, for example, may include a thermocouple, a thermistor, a resistance thermometer bulb or the like.

The heat transfer sheet24is provided between the front surface of the second part22B and the rear surface of the RFIC3of the radio communication module1. The heat transfer sheet24contacts the front surface of the second part22B and the rear surface of the RFIC3. In the embodiment, a portion of the front surface of the heat transfer sheet24contacts the rear surface of the RFIC3through the temperature monitoring sensor25. It is possible for the heat transfer sheet24to transfer heat from the second part22B to the RFIC3.

The temperature monitoring sensor25may be a sheet like shape. The temperature monitoring sensor25detects the temperature of the RFIC3. The temperature monitoring sensor25, for example, may be a thermocouple. The temperature monitoring sensor25is provided in between the heat transfer sheet24and the RFIC3. The temperature monitoring sensor25, as seen from a thickness direction, is smaller than the RFIC3. By measuring the temperature of the RFIC3by the temperature monitoring sensor25, it is possible to accurately comprehend the temperature of the RFIC3.

The heat spreader22, the heat transfer sheet24and the temperature monitoring sensor25are interposed between the RFIC3of the radio communication module1and the temperature regulator21.

The heat sink26is provided on the rear surface side of the temperature regulator21. The heat sink26, for example, may be a water-cooled, or an air-cooled heat sink or the like. It is desirable for the heat sink26to be a water-cooled heat sink. The heat sink26is placed on the front surface of the support plate13(refer toFIG.2). It is possible for the heat sink26to increase or decrease the temperatures of the temperature regulator21and the RFIC3of the radio communication module1in a short period of time.

The power source27supplies power to the temperature regulator21.

The temperature control unit28adjusts a temperature of the temperature regulator21by controlling the current that flows from the power source27to the temperature regulator21, based on a detected value of the temperature adjusting sensor23.

The dew point meter29measures the dew point inside the housing case30(refer toFIG.2).

As shown inFIG.2, the housing case30houses the radio communication module1and the temperature regulator21. The housing case30includes a case main body31, and a shutter plate32. The case main body31extends to the front side from the front surface of the support plate13. The case main body31includes a bottom plate33, a pair of side plates (not shown in figures), and a top plate35. The shutter plate32functions as a lid element that covers the front surface opening of the case main body31. The shutter plate32for example, is formed of a dielectric foam.

The gas supplier40includes a supply source (not shown in figures) of the dry gas, a plurality of intake passages42, and a plurality of release parts (not shown in figures). The intake passages42guide the dried gas supplied from the supply source to the release parts. The release parts supply dry gas to the inside of the housing case30.

As shown onFIG.1, the motion mechanism50includes a slide rail51and a slider52.

The slide rail51is installed on the base surface of the chamber90. The slide rail51is a straight rail that extends along the X direction. The slider52is provided on the bottom part of the module holding unit10. The slider52is movable along the slide rail51. The module holding unit10is movable along the slide rail51in the X direction due to the slider52. For this reason, it is possible to determine the separation distance from the measurement antenna unit60to the module holding unit10freely.

The measurement antenna unit60includes a supporter61, a second antenna62, and an equivalent isotropic radiated power measurement unit63.

The second antenna62transmits and receives measurement radio waves. The second antenna62, for example, transmits and receives high frequency signals of millimeter wave bands. For frequencies of high frequency signals, for example, 10 GHz to 300 GHz, or 60 GHz to 80 GHz and so on may be mentioned. The second antenna62is installed so as to oppose the radio communication module1. The second antenna62is capable of radio communication with a first antenna5of the radio communication module1. The second antenna62is provided on the front surface side of the supporter61.

The equivalent isotropic radiated power measurement unit63(measurement unit) measures the equivalent isotropic radiated power (EIRP) of the radio signal received by the second antenna62. The equivalent isotropic radiated power measurement unit63for example, may be a wattmeter that measures high-frequency power. Equivalent isotropic radiated power is also referred to as “effective isotropic radiated power”. The equivalent isotropic radiated power measurement unit63is supported by the supporter61. The equivalent isotropic radiated power measurement unit63is also referred to as a “power measurement unit63”.

The chamber90houses the module holding unit10, the temperature adjusting mechanism20, the housing case30, the gas supplier40, the motion mechanism50, and the measurement antenna unit60. A radio wave absorber91is provided on an inner surface of the chamber90. The chamber90is not affected by electromagnetic waves from its surroundings, and it is possible for the chamber90to suppress electromagnetic waves from escaping to the surroundings. It is possible for the chamber90to suppress electromagnetic waves from echoing on the inside of the chamber90.

[Output Control Method of the Radio Communication Module]

An output control method of the radio communication module1which includes the first antenna5by using the output control unit100shown inFIG.1is explained.

FIG.5is a block diagram of an output control unit100of a first embodiment.

As shown inFIG.5, the output control unit100includes the temperature adjusting mechanism20(refer toFIG.3andFIG.4), a signal setting unit101, a variable gain amplifier102, an amplifier103, a directional coupler104, a wave detector105, an ALC control unit106, the second antenna62(refer toFIG.1), a power detection unit110, the power measurement unit63, an output judgement unit108, and a threshold value setting unit109.

The signal setting unit101sends a transmission signal of a predetermined frequency, forcing the first antenna5to transmit a radio signal. In the signal setting unit101, it is possible to modulate the transmission signal to be compatible with the radio communication.

The variable gain amplifier102is able to control the transmission power of the transmission signal from the signal setting unit101. The variable gain amplifier102changes the gain based on a threshold value set in the threshold value setting unit109such that the power value obtained at the wave detector105is within the threshold value, and controls the transmission power.

The amplifier103amplifies the transmission signal from the variable gain amplifier102to be compatible with the level of the radio communication.

The directional coupler104distributes the transmission signal from the amplifier103to the first antenna5and the wave detector105.

The first antenna5receives a transmission signal from the directional coupler104and transmits a radio signal. The radio signal transmitted by the first antenna5is a signal that the transmission signal from the signal setting unit101has been amplified.

An ALC control system107is configured from the variable gain amplifier102, the amplifier103, the directional coupler104, the wave detector105, and the ALC control unit106.

“ALC” stands for “Automatic Level Control”. The ALC control unit is the “automatic level control unit”. The ALC control system is the “automatic level control system”.

The wave detector105detects the transmission power of the transmission signal (a signal that the transmission signal from the signal setting unit101is amplified) from the directional coupler104, and obtains a power value.

The ALC control unit106compares the power value obtained at the wave detector105with a predetermined threshold value of power, and obtains the difference between the power value and the threshold value as a comparative result. Here, the predetermined threshold value of power may for example, be determined based on a regulated value of the transmission power required by the Radio Act. The predetermined threshold value of the power may also be a value in the range determined by the product specification.

The ALC control unit106adjusts the gain of the variable gain amplifier102based on the comparative result mentioned above.

Also, the configuration of the ALC control system is not limited to the example explained herewith.

The second antenna62receives the radio signal transmitted by the first antenna5.

The power detection unit110detects the power of the radio signal received by the second antenna62.

The power measurement unit63measures the equivalent isotropic radiated power (EIRP) based on the detected value obtained at the power detection unit110.

The output judgement unit108judges whether the equivalent isotropic radiated power obtained in the power measurement unit63is within the range predetermined by a specification or not. The predetermined range of the equivalent isotropic radiated power determined by a specification for example, may be determined based on a regulated value of the transmission power required by the Radio Act. The predetermined range of the equivalent isotropic radiated power determined by a specification may also be a range determined by the product specification.

FIG.6is a flow diagram showing an output control method of a radio communication module of the first embodiment. From hereon, an output control method of the first embodiment is explained referring toFIG.6.

(Step S1) The signal setting unit101sets the frequency of the transmission signal (frequency setting step). In the case where the radio communication module1capable of transmitting and receiving multiple channels is used, the transmission signal frequency may be, for example, a single frequency of a channel chosen from a plurality of channels. In the embodiment, the frequency is set to “the first frequency”.

(Step S2) The temperature adjusting mechanism20renders the radio communication module1to be a predetermined set temperature. In the embodiment, the set temperature is “the first temperature”.

As shown inFIG.3andFIG.4, by using the temperature regulator21, the temperature of the radio communication module1is set (temperature adjustment step). The temperature control unit28is able to adjust the temperature of the temperature regulator21by controlling the current that flows from the power source27to the temperature regulator21based on a detected value of the temperature adjusting sensor23. The temperature control unit28, for example, is able to raise the temperature of the temperature regulator21by increasing the current that flows to the temperature regulator21when the detected value is less than a lower limit value of a predetermined set range. The temperature control unit28, for example is able to lower the temperature of the temperature regulator21by decreasing the current that flows to the temperature regulator21when the detected value is greater than an upper limit value of a predetermined set range. From this, the temperature of the radio communication module1is set to a target temperature.

(Step S3) The threshold value setting unit109sets the threshold value used in the ALC control (refer toFIG.6).

As shown inFIG.5, the ALC control unit106compares the power value obtained at the wave detector105and the threshold value. In the case where the power value is not within the threshold value, as shown in the following, the gain of the variable gain amplifier102is adjusted.

The variable gain amplifier102controls the transmission power of the transmission signal based on the control signal from the ALC control unit106(feedback control step). For example, in the case where the power value obtained at the wave detector105exceeds the upper limit value of the range of the threshold value, the gain of the variable gain amplifier102is decreased, lowering the transmission power. In the case where the power value is below the lower limit value of the range of the threshold value, the gain of the variable gain amplifier102is increased, raising the transmission power. In this manner, the ALC control unit106controls the output (transmission power) of the transmission signal based on the comparative result of the power value of the transmission signal (a signal that the transmission signal from the signal setting unit101has been amplified) obtained at the wave detector105and the threshold value.

(Step S4) The first antenna5receives the transmission signal from the directional coupler104, and transmits the radio signal (transmission step).

The second antenna62receives a radio signal from the first antenna5. The power detection unit110detects the power of the radio signal received by the second antenna62. The power measurement unit63measures the equivalent isotropic radiated power (EIRP) based on the detected value obtained at the power detection unit110(measurement step) (refer toFIG.6). Step S4includes the transmission step and the measurement step.

(Step S5) The output judgement unit108judges whether the equivalent isotropic radiated power measured in the power measurement unit63is within a predetermined range that is preset. In the case where the obtained judgement result indicates that the equivalent isotropic radiated power is not within the above mentioned range, the step is returned to step S3, and the threshold value is changed (reset) in the threshold setting unit109.

When the threshold value is changed, the difference between the power value of the transmission signal (a signal that the transmission signal from the signal setting unit101has been amplified) obtained from the wave detector105and the threshold value changes. For this reason, the control signal from the ALC control unit106to the variable gain amplifier102changes, as well as the transmission power of the transmission signal from the variable gain amplifier102changes. As a result, the power of the radio signal (a signal that the transmission signal from the signal setting unit101has been amplified) which the first antenna5transmits changes. From this, the power of the radio signal detected at the power detection unit110changes, as well as the equivalent isotropic radiated power obtained at the power measurement unit63changes.

As shown inFIG.6, in step S5, in the case where the equivalent isotropic radiated power is judged not to be within the predetermined range, once again, the step is returned to step S3.

Accordingly, when the equivalent isotropic radiated power is judged not to be within the predetermined range, steps S3to S5are repeated until the equivalent isotropic radiated power is judged to be within the predetermined range.

In the case where the equivalent isotropic radiated power is judged to be within the predetermined range, the threshold value is not changed, and the step is returned to step S1. The threshold value is judged to be appropriate. From this, an appropriate threshold value is determined at the first frequency and the first temperature. In this manner, the output of the transmission signal (transmission power) is adjusted (output control step). Since the output judgement unit108conducts the above mentioned judgement, the output judgement unit108is involved in the adjustment step of the output of the transmission signal.

The set temperature may be changed from the first temperature to the second temperature, and the same output control may be conducted. From this, an appropriate threshold value at the second temperature is obtained.

The equivalent isotropic radiated power typically has a tendency to increase as the temperature decreases. Temperature characteristics exist in the ALC control as well, and the more the temperature decrease the more the equivalent isotropic radiated power tends to increase. For this reason, in the case where the first temperature is close to the lower limit temperature (for example −10 degrees C.) in the operating environment of the radio communication module1, it is possible to comprehend a value close to the upper limit value of the variation range of the equivalent isotropic radiated power. As such, it is easier to avoid having the transmission power surpass a regulated value (for example, a value regulated by the Radio Act).

In the case where the second temperature is a high temperature (for example 60 degrees Celsius) in the operating environment of the radio communication module1, it is possible to comprehend a value close to the lower limit value of the variation range of the equivalent isotropic radiated power. As such, it is possible to avoid having the transmission power greatly fall short of a value determined by product specifications.

The number of temperature conditions required to determine an appropriate threshold value is not limited to one or two. The number of the temperature conditions may be one, or may be a plurality (an arbitrary number greater than or equal to two).

In the case where an appropriate threshold value of a frequency (a second frequency) different than the frequency of the first frequency is needed, the signal setting unit101changes (resets) the frequency in step S1to the frequency of the second frequency. The second frequency may be a frequency of a different channel chosen from a plurality of channels. Similar to the output control in the first frequency, an appropriate threshold value in the second frequency is determined (steps S2to S5). The number of frequency conditions needed for determining an appropriate threshold value is not limited to one or two. The number of frequency conditions may be one, or may be a plurality (an arbitrary number greater than or equal to two).

In the case where no new frequency needs to be set, the step terminates (step S1).

[Manufacturing Method of Radio Communication Module Including Threshold Value Information]

The “appropriate threshold value” obtained at the output control method mentioned above is able to be recorded to the memory unit6of the RFIC3(refer toFIG.4). Based off of this, it is possible to obtain the radio communication module1including the information of the appropriate threshold value. As such, output control becomes easier by the threshold value included in the memory unit6which is specific to each radio communication module1.

[Effects that the Output Control Method in the First Embodiment Achieves]

According to the output control method of the embodiment, since an output (transmission power) of the transmission signal is adjusted based on the equivalent isotropic radiated power of the radio signal transmitted from the radio communication module1, it is possible to accurately adjust the output of the transmission signal. As such, even in the case where fluctuations in frequency characteristics of an antenna, characteristic variations for each module or the like occurs, it is possible to avoid having the transmission power exceed a regulated value. Also, it is also possible to suppress a divergence of a transmission power from values determined by product specifications.

According to the output control method of the embodiment, in the output control step, it is determined whether the equivalent isotropic radiated power is within a predetermined range or not, and based on the judgement result, the threshold value is changed (reset) as needed. From this, it is possible to determine an appropriate threshold value by simple processing.

According to the output control method of the embodiment, it is possible to control the output at a plurality of set temperatures (for example, the first temperature and the second temperature). In this case, it is possible to avoid having the transmission power exceed a regulated value, and it is possible to avoid having the transmission power greatly be below a value determined by the product specifications. As such, it is possible to increase the stability of the transmission power.

The temperature adjusting mechanism20includes the heat spreader22, the temperature adjusting sensor23, and the temperature control unit28. The temperature control unit28adjusts the temperature of the temperature regulator21by controlling the current that flows from the power source27to the temperature regulator21, based off of the detected value of the temperature adjusting sensor23. As such, it is possible to stably determine the temperature of the radio communication module1. As such, it is possible to accurately adjust the output (transmission power) of the transmission signal of the radio communication module1according to the temperature of the radio communication module1. Also, it is possible to determine the threshold value of the radio communication module1at the lower limit and the upper limit temperatures in the operating environment of the radio communication module1.

The temperature regulator21is in direct or in indirect contact with the radio communication module1so as be capable of transferring heat. For this reason, as opposed to the case of determining a temperature of the radio communication module1by adjusting a temperature of the gas inside the chamber90, it is possible to have the temperature of the radio communication module1reach a target temperature in a short period of time. Further, since heat transfer configured to be through direct or indirect contact with the temperature regulator21is used, it is possible to stably determine the temperature of the radio communication module1. As such, it is possible to accurately adjust the output (transmission power) of the transmission signal of the radio communication module1.

[Effects that the Output Control Unit in the Embodiment Achieves]

According to the output control unit100of the embodiment, since the output (transmission power) of the transmission signal is adjusted based on the equivalent isotropic radiated power of radio signal transmitted from the radio communication module1, it is possible to accurately adjust the output of the transmission signal. As such, even in the case where fluctuations in frequency characteristics of an antenna, characteristic variations for each module or the like occurs, it is possible to avoid having the transmission power exceed a regulated value. Also, it is possible to suppress a divergence of a transmission power on values determined by product specifications.

Second Embodiment

FIG.7is a block diagram of an output control unit200of a second embodiment.FIG.8is a flow diagram showing an output control method of a radio communication module of a second embodiment. The same or equivalent configurations as those in the first embodiment shown inFIG.5andFIG.6are designated by the same reference signs, and descriptions thereof are simplified or omitted.

As shown inFIG.7, the aspect which the output control unit200differs from the output control unit100shown inFIG.5is that the output control unit200includes a gain judgement unit111.

The output control method of the second embodiment is explained in detail referring toFIG.8.

As shown inFIG.8, steps S1to S3are similar to the output control method of the first embodiment shown inFIG.6. The primary set temperature is the first temperature. The frequency is the first frequency. The power value obtained at the wave detector105is for example within the range of the threshold value mentioned above.

(Step S104) The first antenna5receives the transmission signal (a signal that the transmission signal from the signal setting unit101has been amplified) from the directional coupler104, and transmits the radio signal (transmission step). The second antenna62receives a radio signal from the first antenna5. The power detection unit110detects the power of the radio signal received by the second antenna62. The power measurement unit63measures the equivalent isotropic radiated power (EIRP) based on the detected value obtained at the power detection unit110(measurement step).

The ALC control unit106calculates the gain value based on the difference between the power value obtained at the wave detector105and the threshold value.

(Step S105) The set temperature of the radio communication module1is set to the second temperature that is a temperature higher than the first temperature.

(Step S106) The first antenna5transmits a radio signal (transmission step). The second antenna62receives the radio signal. The power detection unit110detects the power of the radio signal received by the second antenna62. The power measurement unit63measures the equivalent isotropic radiated power (EIRP) based on the detected value (measurement step). The ALC control unit106calculates the gain value based on the difference between the power value obtained at the wave detector105and the threshold value.

(Step S107) The gain judgement unit111(refer toFIG.7) compares the gain value calculated at step S104and the gain value calculated at step S106. The gain judgement unit111judges whether the gain value of the case where the set temperature is the second temperature is changed with respect to the gain value of the case where the set temperature is the first temperature, or not. In the case where the power value obtained at the wave detector105is within the range of the threshold value, the gain value does not change. If the power value is off from the range of the threshold value, the gain value changes.

In the case where there is no change in the gain value, the step is returned to step S105. With the set temperature being a higher temperature (Step S105), the first antenna5transmits a radio signal. The power measurement unit63measures the equivalent isotropic radiated power. The ALC control unit106calculates the gain value (step S106). The gain judgement unit111judges whether the gain value is changed, or not based on the comparative result of a plurality of gain values (specifically, the change of the gain value with respect to the previous gain value).

In this manner, as the set temperature is increased step by step, cycles of the steps S105to S107are repeated until the gain value changes. In the case the gain value changes, step S108below is conducted.

(Step S108) The output judgement unit108judges whether the equivalent isotropic radiated power is within a predetermined range or not in a cycle (referred to as “prior cycle”) that is one cycle before the cycle where change of the gain value occurred. If a judgement result that indicates the equivalent isotropic radiated power is not within the predetermined range is obtained, the step is returned to step S3, and changing (resetting) of the threshold value is conducted.

In the case where the equivalent isotropic radiated power in the prior cycle is judged to be within a predetermined range, changing of the threshold value is not conducted, and the step is returned to step S1. The threshold value in the prior cycle is judged to be appropriate. From this, an appropriate threshold value is determined. In this manner, the output (transmission power) of the transmission signal is adjusted (output control step).

The primary set temperature may be changed from the first temperature to the second temperature, and similar output control may be conducted. The number of temperature conditions needed to decide an appropriate threshold value may be one, or may be a plurality (an arbitrary number greater than or equal to two).

In the case where an appropriate threshold value of a frequency (a second frequency) different than the frequency of the first frequency is needed, the signal setting unit101changes (resets) the frequency in step S1to the frequency of the second frequency. The number of frequency conditions needed for determining an appropriate threshold value may be one, or may be a plurality (an arbitrary number greater than or equal to two).

Furthermore, although in the embodiment, as the set temperature is increased step by step, cycles of the steps S105to S107are repeated, cycles of the steps S105to S107may be repeated as the set temperature is decreased step by step.

[Effects that the Output Control Method of the Second Embodiment Achieves]

According to the output control method of the embodiment, since an output (transmission power) of the transmission signal is adjusted based on the equivalent isotropic radiated power of the radio signal transmitted from the radio communication module1, it is possible to accurately adjust the output of the transmission signal. As such, even in the case where fluctuations in frequency characteristics of an antenna, characteristic variations for each module or the like occurs, it is possible to avoid having the transmission power exceed a regulated value. Also, it is also possible to suppress a divergence of a transmission power on values determined by product specifications

In an output control method of this embodiment, gain values are calculated at each set temperature which varies with one another, and a threshold value is changed (reset) as needed, based on the comparative result of the plurality of the gain values (specifically, the change in the gain value as compared to the prior gain value). For this reason, with simple processing, it is possible to more accurately determine an appropriate threshold value compared to the first embodiment.

The technical scope of the present invention is not limited to any of the previously mentioned embodiments, and it is possible to apply appropriate changes so long as they do not depart from the objective of the present invention.

As the temperature regulator21shown onFIG.3andFIG.4, a Peltier element was used as an example. However, the temperature regulator is not limited thereto. The temperature regulator may be a heater of a heating wire or the like of a nichrome wire or the like. The temperature regulator may include a heating medium circulation structure that distributes the heat medium (fluid body). Also, the temperature regulator may include a cooling mechanism such as a chiller (a device that circulates cool water) or the like.

EXPLANATION OF REFERENCE SYMBOLS