JP2010041366A - Base station and wireless communication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a base station and a wireless communication method, reducing power consumption by devising an allocation method of a communication signal of a wireless communication terminal to a time slot. <P>SOLUTION: A base station 120 coping with the TDMA/TDD system has: a band pass filter 190 that extracts a predetermined band component of a communication signal with a wireless communication terminal; an amplifier circuit 192 that amplifies the communication signal; a slot allocation part 188 that allocates the communication signal of the wireless communication terminal from which a communication request is transmitted to an arbitrary time slot; a power supply controller 194 that powers up the power supply of the band pass filter and the amplifier circuit in advance by a predetermined time period of starting point of the allocated time slot; and powers off at the time of allocated time slot termination. The slot allocation part allocates a plurality of communication signals of wireless communication terminal to time slots adjacent to each other when the communication request is transmitted from a plurality of wireless communication terminals. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a base station and a wireless communication method capable of wireless communication with a plurality of wireless communication terminals using the TDMA / TDD scheme.

  In recent years, wireless communication terminals represented by PHS (Personal Handy phone System) and mobile phones have become widespread, and it has become possible to make calls and obtain information regardless of location or time. Such a wireless communication terminal is connected to a communication network by performing wireless communication with a base station installed at a predetermined location.

  In wireless communication using PHS or the like, for example, TDMA / TDD (TDMA: Time Division Multiple Access, TDD: Time Division Duplex) is used.

  The TDD scheme is a scheme in which, for example, a radio communication terminal (PS: Personal Station) and a base station (CS: Cell Station) switch communication timings from one to the other and from the other to the other alternately and in a short time. In wireless communication using the TDD scheme, a mobile station receives data at a timing when the base station transmits, and conversely, a base station receives data at a timing when the mobile station transmits. Such switching control is executed via an RF (Radio Frequency) circuit. The RF circuit is an analog circuit that can transmit and receive high-frequency radio waves, and includes a transmission circuit and a reception circuit that can operate independently.

  The TDMA method is a method of subdividing into a plurality of time slots on the time axis and performing communication in parallel with a plurality of opponents through the subdivided time slots. In the TDMA scheme, a mobile station can communicate with a plurality of base stations using different channels, or can communicate with a single base station using different channels.

In the base station, the transmitter / receiver circuit is always powered on in order to perform radio communication in parallel with a plurality of radio communication terminals using the TDMA / TDD scheme described above, and a great amount of power is consumed. Therefore, Patent Document 1 describes that in a TDMA / TDD wireless base station, the power consumption of the base station wireless device is reduced, and problems such as insufficient battery capacity and increased heat generation during a power failure are described. Specifically, the technique is to turn off or power down a receiving circuit that is an unused slot among time slots for a call channel.
JP-A-11-136158

  However, in the technique of Patent Document 1, power consumption can be suppressed for the receiving circuit, but the conventional circuit is used as it is for the transmitting circuit. For this reason, there has been a limit to further power saving.

  On the other hand, in an IF (Intermediate Frequency) circuit including a band-pass filter and an amplifier circuit in an RF circuit used for transmission, the temperature of the semiconductor becomes unbalanced by turning on / off the power of this circuit. As a result, a drop phenomenon in which the gain of the amplifier circuit fluctuates often occurs, which affects the modulation accuracy. In order to suppress the Drop phenomenon, it is necessary to stabilize the temperature of the IF circuit. However, it is known that it takes time until the data can be stably transmitted after the power is turned on. Therefore, the IF circuit needs to be turned on prior to actual transmission, which is a serious problem in promoting power saving of the base station.

  In view of such a problem, the present invention can reduce power consumption when it is necessary to supply power to the band-pass filter and the amplifier circuit earlier than the start of the assigned time slot. It is an object to provide a base station and a wireless communication method.

  In order to solve the above problems, a typical configuration of the present invention is a base station capable of wireless communication using a plurality of time slots according to a TDMA / TDD scheme with a plurality of wireless communication terminals, A band-pass filter that extracts a predetermined band component of the communication signal, an amplifier circuit that amplifies the communication signal, a slot allocation unit that allocates the communication signal of the wireless communication terminal that requested communication to an arbitrary time slot, A power control unit that turns on the power of the bandpass filter and the amplifier circuit from a predetermined time before the start time of the time slot and disconnects at the end of the assigned time slot, and the slot allocation unit includes a plurality of communication signals. A base station characterized by allocating a plurality of communication signals to adjacent time slots when there is a communication request by.

  An IF circuit including a band pass filter and an amplifier circuit needs to be turned on early (at least a predetermined time before) in order to operate stably. However, if the time slots to which the communication signals of the wireless communication terminals are assigned are separated, the power on from the predetermined time before will be turned on. Therefore, the slot assigning unit assigns the communication signal of the wireless communication terminal to a time slot adjacent to the time slot to which the communication signal has already been assigned, and makes the assigned time slot continuous so that the power supply from a predetermined time before is supplied. Therefore, it is possible to reduce the number of times the power is input, and to reduce wasteful power consumption for stabilizing the IF circuit.

  The band-pass filter and the amplifier circuit may be provided for each communication signal having a different bandwidth, and the slot allocation unit may allocate a communication signal of a wireless communication terminal having a common bandwidth of the communication signal to an adjacent time slot. .

  When a wireless communication system based on a plurality of bandwidths is adopted, band pass filters (IF circuits) corresponding to the respective bandwidths are prepared. In the present invention, power is turned on independently for each IF circuit including a plurality of such bandpass filters. In addition, by making consecutive assigned time slots in each bandwidth, it is possible to suppress the power-on from a predetermined time before the above-described invention, and wasteful power for stabilizing the IF circuit can be suppressed. Consumption can be reduced. In addition, it is possible to further reduce power consumption by continuously assigning communication signal groups having different bandwidths to time slots.

  The slot allocating unit may release the communication signal of the assigned wireless communication terminal in response to a release request from the wireless communication terminal, and reassign another communication signal that has not been released to the adjacent time slot.

  With such a configuration, even if the communication signal of the wireless communication terminal is released, it is possible to maintain a continuous state of assigned time slots, and to continue to reduce power consumption.

  Another representative configuration of the present invention is capable of wireless communication using a plurality of time slots based on the TDMA / TDD scheme with a plurality of wireless communication terminals, and extracts a predetermined band component of a communication signal with the wireless communication terminal. A wireless communication method for establishing wireless communication with a wireless communication terminal in a base station having a band-pass filter and an amplifier circuit for amplifying a communication signal. When a communication request is received from the wireless communication terminal, wireless communication is still performed in a time slot. If the communication signal of the terminal is not assigned, the communication signal of the wireless communication terminal that requested the communication is assigned to an arbitrary time slot, and if already assigned, the time slot adjacent to the already assigned time slot is assigned. Assign the communication signal of the wireless communication terminal that requested the communication, and whether it is a predetermined time before the start of the assigned time slot Bandpass Power filter and amplifier circuit, characterized by cutting at the end of the assigned time slot.

  The component corresponding to the technical idea in the base station mentioned above and its description are applicable also to the said radio | wireless communication method.

  As described above, according to the present invention, when it is necessary to supply power to the band pass filter and the amplifier circuit earlier than the start of the assigned time slot, it is possible to reduce power consumption.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiment are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

(First embodiment)
Here, in order to facilitate understanding of the present embodiment, the entire wireless communication system will be described first, and then the specific configuration of the base station will be described.

(Wireless communication system 100)
FIG. 1 is an explanatory diagram showing a schematic connection relationship of the wireless communication system 100. The wireless communication system 100 includes a PHS terminal 110 (110A, 110B, 110C) as a wireless communication terminal, a base station 120 (120A, 120B), an ISDN (Integrated Services Digital Network) line, the Internet, a dedicated line, and the like. The communication network 130 and the relay server 140 are configured.

  Here, the PHS terminal 110 is cited as a wireless communication terminal. However, the present invention is not limited to such a case. A mobile phone, a notebook personal computer, a PDA (Personal Digital Assistant), a digital camera, a music player, a car navigation system, a portable TV, a game Various electronic devices capable of wireless communication such as a device, a DVD player, and a remote controller can also be used as a wireless communication terminal.

  In the wireless communication system 100, when a user connects a communication line from his / her PHS terminal 110A to another PHS terminal 110C, the PHS terminal 110A makes a wireless connection request to the base station 120A within the communicable range. . The base station 120A that has received the wireless connection request requests the relay server 140 to establish a communication connection with the communication partner via the communication network 130, and the relay server 140 refers to the location registration information and determines the other PHS terminal 110C. The base station 120B within the wireless communication range is selected to secure a communication path between the base station 120A and the base station 120B, and communication between the PHS terminal 110A and the PHS terminal 110C is established.

  Since such a radio communication system 100 employs a time division method, the radio communication circuits of the base station 120 and the PHS terminal 110 need not always function. Therefore, the power can be reduced by turning off the power during the non-functioning time. An object of the present embodiment is to control the power supply of the radio communication circuit of the base station 120 and further reduce the power consumption by devising how to allocate the communication signal of the PHS terminal 110 to the time slot.

(Base station 120)
FIG. 2 is a block diagram illustrating a schematic configuration of the base station 120. The base station 120 includes a base station control unit 180, a base station memory 182, a base station wireless communication unit 184, and a base station wired communication unit 186.

  The base station control unit 180 manages and controls the entire base station 120 using a semiconductor integrated circuit including a central processing unit (CPU). The base station control unit 180 uses the program in the base station memory 182 to perform wireless communication with the PHS terminal 110, communication connection from the PHS terminal 110 to another PHS terminal 110, and the like. In addition, when there are communication requests from a plurality of PHS terminals 110, or when there is a communication request that desires to use a plurality of time slots from one PHS terminal 110, the base station control unit 180 is configured to output the plurality of communication signals. Also functions as a slot allocation unit 188 that allocates to a time slot adjacent to the allocated time slot. With such a configuration in which the communication signal is allocated adjacent to the assigned time slot, the assigned time slots are continuous.

  The base station memory 182 includes a ROM, a RAM, an EEPROM, a nonvolatile RAM, a flash memory, or an HDD, and stores a program processed by the base station control unit 180.

  The base station wireless communication unit 184 establishes communication with the PHS terminal 110. The base station wired communication unit 186 can be connected to various servers including the relay server 140 via the communication network 130. The base station wireless communication unit 184 also includes a band-pass filter 190 that extracts a predetermined band component of a communication signal with the PHS terminal 110, an amplification circuit 192 that amplifies the extracted communication signal, a band-pass filter 190, and an amplification. It also functions as a power control unit 194 that turns on the power of the IF circuit including the circuit 192 for a predetermined time before the start of the assigned time slot and disconnects it at the end of the assigned time slot. Here, as the predetermined time, a time shorter than the time slot time length can be selected, but it is desirable to set the time length to one time slot time for the reason described later.

  FIG. 3 is a block diagram showing a specific configuration of the base station radio communication unit 184. In the following embodiments, in order to facilitate understanding, reference is made in particular to the transmission circuit among the transmission / reception circuits, and the description of the reception circuit is omitted, but it goes without saying that the description of the transmission circuit also applies to the reception circuit. Yes.

  The base station wireless communication unit 184 has a function of transmitting voice and data transmitted from the communication network 130 via the base station wired communication unit 186 to the PHS terminal 110. Specifically, the base station wireless communication unit 184 includes a D / A (Digital-to-Analog) circuit 200, a first IF circuit 202, a second IF circuit 204, an RF circuit 206, and a power supply as a data path. A power source unit 208, a switch 210, and a power source control unit 194 are configured as paths.

  The D / A circuit 200 converts a digital signal into an analog signal. The first IF circuit 202 and the second IF circuit 204 convert the analog signal converted by the D / A circuit 200 into a predetermined intermediate frequency. In this embodiment, transmission using the superheterodyne method is performed, and two-stage frequency conversion is performed as an IF circuit. The first IF circuit 202 and the second IF circuit 204 include a band pass filter 190 and an amplifier circuit 192, respectively. The RF circuit 206 forms an electrical signal that can be emitted as an electromagnetic wave from the analog signal formed through the IF circuits 202 and 204.

  The power supply unit 208 supplies power to the base station wireless communication unit 184. The power supply control unit 194 controls the power supply from the power supply unit 208 to the D / A circuit 200, the first IF circuit 202, the second IF circuit 204, and the RF circuit 206 by turning on / off the switch 210.

(Wireless communication method)
Hereinafter, a wireless communication method in which the base station 120 described above receives a communication request from the PHS terminal 110, assigns a communication signal of the PHS terminal 110 to a time slot, and establishes wireless communication will be described. Here, for convenience, numbers (1, 2, 3, 4) are assigned in order from the time slot of the earliest time, and are attached to the “time slot”, for example, “time slot 1”.

  FIG. 4 is a flowchart showing a processing flow of the wireless communication method according to the present embodiment. The slot allocation unit 188 of the base station 120 waits for a communication request from the PHS terminal 110 (S250), and when there is a new communication request from the PHS terminal 110 (“YES” in S250), the slot allocation unit 188 It is determined whether there is an empty slot that has not yet been allocated (S252). If it is determined that there is an empty slot (“YES” in S252), the communication signal of the PHS terminal 110 is assigned to the empty slot (S254). If there is no empty slot (“NO” in S252), the PHS The terminal 110 is notified that allocation cannot be performed (S256). At this time, the slot allocation unit 188 transmits the allocation information of the allocated time slot to the power supply control unit 194 in order to secure the power supply of the allocated time slot. When the correspondence to the PHS terminal 110 is completed, the communication request waiting state (S250) is resumed.

  The allocation of the communication signal of the PHS terminal 110 to the empty slot (S254) is executed for the earliest time slot among the empty slots. In this way, each communication signal of the PHS terminal 110 is assigned so as to be contiguous from the earlier one among the plurality of time slots.

  Further, when there is no new communication request from the PHS terminal 110 (“NO” in S250), it is determined whether or not there is a request for releasing the communication signal from the time slot of the communication signal with which the PHS terminal 110 has established communication. If there is a release request (“YES” in S260), the slot assignment unit 188 releases the communication signal of the assigned PHS terminal 110 in response to the release request from the PHS terminal 110 (S262). ) Reassign other unreleased communication signals to time slots adjacent to the assigned time slots so that the assigned time slots are adjacent to maintain a continuous state of the assigned time slots ( S264). In this way, even if the communication signal of the PHS terminal 110 is released, it is possible to maintain a continuous state of assigned time slots, and to continue to reduce power consumption.

  In this embodiment, by making the assigned time slots continuous, it is possible to suppress the number of times the power is turned on for a predetermined time before operating the first IF circuit 202, the second IF circuit 204, etc. Reduction is achieved. Hereinafter, it will be described in detail on the assumption that the predetermined time is set as one time slot.

  FIG. 5 is an explanatory diagram for explaining reduction of power consumption by time slot allocation. Here, it is assumed that an arbitrary base station 120 establishes wireless communication with two PHS terminals 110A and 110B. The power control unit 194 turns on the power one time slot earlier than the start time of the assigned time slot, and turns off the power at the end time of the assigned time slot.

  Without applying this embodiment, the base station 120 randomly assigns the communication signals of the two PHS terminals 110A and 110B for which there was a communication request. For example, as shown in FIG. It is assumed that the communication signal and the communication signal of the PHS terminal 110B are arranged separately in the time slot 2 and the time slot 4, respectively. Here, in order to stabilize the first IF circuit 202 and the second IF circuit 204 including the band pass filter 190 and the amplifier circuit 192, the power is turned on earlier by one time slot, so the time during which the switch 210 is turned on. Is four time slots from time slot 1 to time slot 4 as shown in FIG. As described above, when the time slots to which the communication signals of the PHS terminal 110 are allocated are separated from each other, the power-on from a predetermined time before is overrun.

  On the other hand, when the present embodiment is applied, as described above, the slot allocation unit 188 sequentially allocates communication signals of the PHS terminal 110A and the PHS terminal 110B from the earliest time slot, and as shown in FIG. The communication signals of the two PHS terminals 110A and 110B are continuously arranged in time slot 1 and time slot 2, respectively.

  Again, in order to stabilize the first IF circuit 202 and the second IF circuit 204, the power must be turned on by one time slot earlier. However, for the time slot 2, the power is already turned on in the time slot 1. It is not necessary to turn on the power before a predetermined time, and the time during which the switch 210 is turned on is only three time slots as shown in FIG. Thus, by defining the assignment procedure between the communication signal of the PHS terminal 110A and the communication signal of the PHS terminal 110B, it is possible to suppress the number of times of power-on from a predetermined time before, for example, one time. It is possible to reduce wasteful power consumption for stabilizing the circuit 202 and the second IF circuit 204.

  In the present embodiment, the slots are assigned so as to be continuous from the earliest time slot, but the slots may be assigned by a method of continuing from the latest time slot. This is also because the power-on time can be shortened.

(Second Embodiment)
In the first embodiment described above, the time slot allocation in the case of using a wireless communication system with a single bandwidth has been described. However, in the second embodiment, wireless communication systems with a plurality of different bandwidths are used. Time slot allocation will be described.

  FIG. 6 is a block diagram showing a schematic configuration of the base station 320 in the second embodiment. The difference from FIG. 3 is that a plurality of band-pass filters (band-pass filter 190A and band-pass filter 190B) are installed in the base station radio communication unit 322.

  When the wireless communication system adopts a plurality of bandwidths, for example, 300 kHz and 900 kHz, in the wireless communication system 100, the base station 320 is provided with band-pass filters 190A and 190B corresponding to the respective bandwidths. . In the present embodiment, power is turned on independently for a plurality of IF circuits including the plurality of bandpass filters 190A and 190B.

  FIG. 7 is a block diagram showing the configuration of the base station wireless communication unit 322 according to the second embodiment. The base station radio communication unit 322 includes a D / A circuit 200, a first IF circuit 202, RF switches 350A and 350B, second IF circuits 204A and 204B, an RF circuit 206, and a power path as a data path. The power supply unit 208, switches 210A, 210B, and 210C, and a power supply control unit 194 are included.

  Since the D / A circuit 200, the first IF circuit 202, the RF circuit 206, and the power supply unit 208, which have already been described as constituent elements in the first embodiment, have substantially the same functions, a duplicate description is omitted here. Now, the RF switches 350A and 350B, the second IF circuits 204A and 204B, the switches 210A, 210B, and 210C, and the power supply control unit 194 that have different configurations will be mainly described.

  The RF switches 350A and 350B correspond to the first IF circuit 202, the RF circuit 206, and the second IF circuits 204A and 204B according to the time slot allocation information using the second IF circuits 204A and 204B transmitted from the slot allocation unit 188. Connect either one.

  The second IF circuits 204A and 204B include amplifier circuits 192A and 192B and band pass filters 190A and 190B that are adapted to different bandwidths, respectively. Note that the bandpass filter 190A and the bandpass filter 190B are not used at the same time.

  The switch 210A turns on / off the connection between the power supply unit 208 and the second IF circuit 204A, the switch 210B turns on / off the connection between the power supply unit 208 and the second IF circuit 204B, and the switch 210C The connection of 208 to the D / A circuit 200, the first IF circuit 202, and the RF circuit 206 is turned ON / OFF.

  The power supply control unit 194 independently controls ON / OFF of the switches 210A, 210B, and 210C, and supplies power to each circuit in the base station wireless communication unit 322 at an appropriate timing.

  When a wireless communication system with a plurality of bandwidths, for example, 300 kHz and 900 kHz, is used, the bandwidth of the bandpass filter for removing nearby spurious is switched according to the transmission bandwidth in order to reduce the nearby spurious as much as possible. Must-have.

  Therefore, when the band-pass filter extends over a plurality of paths, band-pass filters each having a fixed bandwidth are provided in each second IF circuit 204 as shown in FIG.

  When a plurality of band-pass filters are provided in this way and the power supplies of the second IF circuits 204A and 204B including the respective band-pass filters 190A and 190B and the amplifier circuits 192A and 192B are independently operated, the amplifier circuits 192A and 192B are caused. A Drop phenomenon may occur. The “Drop phenomenon” refers to a phenomenon in which the temperature of the semiconductor immediately after power-on becomes unbalanced and the gain of the amplifier circuit fluctuates. When the Drop phenomenon occurs, the original characteristics of the second IF circuits 204A and 204B deteriorate, and the modulation accuracy may be adversely affected.

  In order to avoid deterioration in modulation accuracy due to the Drop phenomenon, it is desirable to turn on the power of the second IF circuits 204A and 204B provided with the amplifier circuits 192A and 192B before a predetermined time using the time slot. However, it is necessary to avoid turning on and off the power supply in the middle of the time slot because the characteristic of the time slot is deteriorated. Therefore, the power-on timing from a predetermined time before is the time slot start and end timing. That is, the predetermined time is desirably an integer multiple of the time slot, and particularly preferably a time length of one time slot.

  FIG. 8 is a flowchart illustrating a processing flow of the wireless communication method according to the second embodiment. Here, two different bandwidths A and B will be described. As in FIG. 4, the slot allocation unit 188 of the base station 320 waits for a communication request from the PHS terminal 110 (S250), and when there is a new communication request from the PHS terminal 110 (“YES” in S250), It is determined whether or not there is an empty slot that has not yet been assigned to the time slot (S252).

  If it is determined that there is an empty slot (“YES” in S252), it is determined whether the bandwidth of the PHS terminal 110 that has requested communication is A or B (S400). When it is determined that the bandwidth is A (“A” in S400), the communication signal of the PHS terminal 110 having the already allocated bandwidth B is shifted to a later time slot, that is, the time slot N (N Is reassigned to the time slot (N + 1) (S402), and communication is performed in the empty slot generated between the PHS terminal 110 with the bandwidth A and the PHS terminal 110 with the bandwidth B. The communication signal of the requested PHS terminal 110 is assigned (S404).

  If there is an empty slot ("YES" in S252) and the bandwidth is determined to be B, if there is an earliest empty slot among empty slots, that is, if there is an assigned time slot, immediately after that time slot If not, the communication signal of the PHS terminal 110 is assigned to the head of the time slot (S406). In S404 and S406, slot allocation unit 188 transmits the time slot allocation information to power supply control unit 194 and RF switches 350A and 350B.

  Based on the allocation information, the power controller 194 turns on the power of the second IF circuit 204A and the second IF circuit 204B through the switches 210A and 210B one time slot earlier than the start time of the allocated time slot. When the assigned time slot ends, the power is turned off, and if a communication signal is assigned to any time slot having a different bandwidth through the switch 210C, one time slot earlier than the start time of the time slot. Turn on the power and turn off at the end of the assigned time slot. Further, the RF switches 350A and 350B also exclusively connect either the second IF circuit 204A or the second IF circuit 204B based on the allocation information from the slot allocation unit 188.

  If there is no empty slot (“NO” in S252), the PHS terminal 110 is notified that allocation cannot be performed (S256). Thus, when the correspondence to the PHS terminal 110 is completed, the communication request waiting state (S250) is resumed.

  Similarly to FIG. 4, when there is no new communication request from the PHS terminal 110 (“NO” in S250), there is a request to release the time slot of the communication signal that the PHS terminal 110 has established communication with. If there is a release request (“YES” in S260), the slot assignment unit 188 sends the communication signal of the assigned PHS terminal 110 in response to the release request from the PHS terminal 110. Release (S262), in order to maintain the continuous state of the assigned time slots, other unreleased communication signals are transferred to the time slots adjacent to the assigned time slots so that the assigned time slots are adjacent to each other. Reassign (S264). In particular, in this embodiment, reassignment is performed so that the communication signals of the PHS terminals 110 of the bandwidths A and B are continuous, and the communication signals of the PHS terminals 110 of the bandwidth A and the bandwidth B are also continuous. It is.

  In such a wireless communication method, the PHS terminals 110 are continuously packed from the earlier of a plurality of time slots, and the order of the PHS terminals 110 with the bandwidth B follows the PHS terminals 110 with the bandwidth A. It becomes a shape.

  In the second embodiment, power is turned on from a predetermined time required to operate a circuit having a common bandwidth, such as the first IF circuit 202, by continuing assigned time slots having the same bandwidth. The number of times the power is turned on before a predetermined time necessary for operating each of the bandpass filters having different bandwidths is also suppressed. Therefore, power consumption can be reduced in all the base station radio communication units 322.

  FIG. 9 is an explanatory diagram for explaining a reduction in power consumption by time slot allocation in the second embodiment. In the present embodiment, as described above, the communication signal of the PHS terminal 110 having the bandwidth A is continuously allocated to the time slot having the earlier time, and the communication signal of the PHS terminal 110 having the bandwidth B is continuously allocated.

  Again, in order to stabilize the first IF circuit 202 and the second IF circuits 204A and 204B, the power must be turned on one time slot earlier, but the first PHS terminal 110 among the PHS terminals 110 in which the assigned time slots are continuous Other than the terminal 110, since the power is already turned on in the time slot of the first PHS terminal 110, it is not necessary to turn on the power before a predetermined time, and the time when the switches 210A, 210B, and 210C are turned on is the target. The time required for the operation of the IF circuit is a time obtained by adding one time slot to the previous stage, and is equivalent to three time slots, two time slots, and four time slots as shown in FIG. By defining the communication signal allocation procedure for a plurality of PHS terminals 110 having different bandwidths in this way, it is possible to suppress the number of times of power-on from a predetermined time before, for example, one time. It is possible to reduce wasteful power consumption for stabilizing the 1IF circuit 202 and the second IF circuit 204.

  FIG. 10 is an explanatory diagram showing an example of communication signal allocation of the PHS terminal 110 using the above-described procedure. Here, in order to facilitate understanding, the PHS terminal 110 having the bandwidth A is set to “A1” and “A2”, and the PHS terminal 110 having the bandwidth B is set to “B1” and “B2”.

  First, the communication signal of the PHS terminal A1 is assigned to the time slot 1 as shown in FIG. Next, when there is a communication request from the PHS terminal B1, a communication signal is assigned to the time slot 2 which is the earliest time slot of the empty slot as shown in FIG. Subsequently, when there is a communication request from the PHS terminal A2, the PHS terminal B1 is first shifted to a later time slot as shown in FIG. Then, as shown in FIG. 10 (d), the communication signal of the PHS terminal A2 is assigned to an empty slot (time slot 2) formed between the PHS terminal A1 and the PHS terminal B1. In this way, the continuous state of the time slots to which the communication signals are allocated by the bandwidth A is ensured.

  Further, when there is a communication request from the PHS terminal B2, the communication signal of the PHS terminal B2 is assigned to the earliest time slot of the empty slot as shown in FIG.

  As described above, when a wireless communication method based on a plurality of bandwidths is adopted, band pass filters (IF circuits) corresponding to the respective bandwidths are prepared. In the second embodiment, power is independently supplied to the second IF circuits 204A and 204B including the plurality of bandpass filters 190A and 190B and the amplifier circuits 192A and 192B. In addition, by making the assigned time slots in each bandwidth continuous, it is possible to suppress the power-on from a predetermined time, for example, once, and useless power to stabilize the IF circuit. Consumption can be reduced. Further, it is possible to further reduce power consumption by continuously assigning communication signal groups having different bandwidths to time slots.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, in the above-described embodiment, two examples of the passband width are increased, 300 kHz and 900 kHz. However, the present invention is not limited to such a numerical value, and any passbandwidth can be taken. Further, the number of band pass filters is not limited.

  Note that each step in the wireless communication method of the present specification does not necessarily have to be processed in time series in the order described in the flowchart, and may include processing in parallel or a subroutine.

  The present invention relates to a base station and a wireless communication method capable of wireless communication with a plurality of wireless communication terminals by a TDMA / TDD system.

It is explanatory drawing which showed the rough connection relation of the radio | wireless communications system. It is the block diagram which showed the hardware constitutions of the PHS base station of 1st Embodiment. It is the block diagram which showed the detailed function of the base station radio | wireless communication part of 1st Embodiment. It is a flowchart explaining time slot allocation of 1st Embodiment. It is the figure which compared the conventional time slot allocation method of 1st Embodiment and this invention. It is the block diagram which showed the hardware constitutions of the PHS base station of 2nd Embodiment. It is the block diagram which showed the detailed function of the base station radio | wireless communication part of 2nd Embodiment. It is a flowchart explaining time slot allocation of 2nd Embodiment. It is the figure which showed the time slot allocation method of 2nd Embodiment. It is the figure which compared the time slot allocation method of the past and 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 110 ... PHS terminal 120, 320 ... Base station 188 ... Slot allocation part 190 ... Band pass filter 192 ... Amplifier circuit 194 ... Power supply control part 202 ... 1st IF circuit 204 ... 2nd IF circuit

Claims (4)

A base station capable of wireless communication with a plurality of wireless communication terminals using a plurality of time slots according to the TDMA / TDD scheme,
A band pass filter for extracting a predetermined band component of a communication signal with the wireless communication terminal;
An amplifier circuit for amplifying the communication signal;
A slot allocation unit that allocates a communication signal of a wireless communication terminal that has made a communication request to an arbitrary time slot;
A power control unit that turns on the power of the bandpass filter and the amplifier circuit from a predetermined time before the start time of the assigned time slot and disconnects at the end of the assigned time slot;
With
The slot allocating unit allocates a plurality of communication signals to adjacent time slots when there is a communication request using a plurality of communication signals. The band pass filter and the amplification circuit are provided for each communication signal having a different bandwidth,
The base station according to claim 1, wherein the slot allocation unit allocates a communication signal of a wireless communication terminal having a common communication signal bandwidth to an adjacent time slot.   The slot allocation unit releases a communication signal of the allocated radio communication terminal in response to a release request from the radio communication terminal, and reallocates another communication signal that has not been released to an adjacent time slot. The base station according to claim 1 or 2. A band-pass filter for extracting a predetermined band component of a communication signal with a wireless communication terminal and an amplifying circuit for amplifying the communication signal, capable of wireless communication using a plurality of time slots according to the TDMA / TDD system with a plurality of wireless communication terminals A wireless communication method for establishing wireless communication with the wireless communication terminal in a base station having
When there is a communication request from the wireless communication terminal, if the communication signal of the wireless communication terminal is not yet assigned to the time slot, the communication signal of the wireless communication terminal that has requested the communication is assigned to an arbitrary time slot, and If assigned, assign the communication signal of the wireless communication terminal that requested the communication to the time slot adjacent to the already assigned time slot,
A wireless communication method comprising: turning on power to the band pass filter and the amplifier circuit from a predetermined time before the start time of the assigned time slot, and disconnecting at the end of the assigned time slot.

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