JP2013013152A - Terminal device, communication method, program, processor, and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce collision probability against a signal transmitted from a terminal device.SOLUTION: A control part 210 transmits a request signal by random access to a base station device in order to establish communication with the base station device. At that time, a pattern determining part 212 generates a request signal by selecting at least one sub-carrier among multi-carrier signals formed of a plurality of sub-carriers. An antenna 200, a radio part 202, a transmitting/receiving part 204, a modulating/demodulating part 206, and an IF part 208 receive a response signal to the transmitted request signal, and then execute communication with the base station device.

Description

  The present invention relates to a radio communication technique, and more particularly to a terminal apparatus and a base station apparatus that perform communication after channel assignment.

In a mobile communication system such as a second generation cordless telephone system, a logical control channel (hereinafter referred to as “LCCH”) as shown in FIG. 1 is defined, and a base station apparatus (CS: Cell Station) Communication is executed by allocating a time slot, which is a unit of communication, to a terminal device (PS: Personal Station).
When the number of groupings is 8, the conventional logical control channel is a broadcast channel (hereinafter referred to as “BCCH”) indicating the start of one system information, eight incoming information channels (hereinafter referred to as “PCH”), 3 It is composed of a total of 12 channels, ie, one channel allocation control channel (hereinafter referred to as “SCCH”), and the base station apparatus intermittently transmits each channel at intervals of 20 frames (for example, see Non-Patent Document 1). ).
Further, as shown in the lower stage, one frame is composed of eight time slots.

ARIB STANDARD RCR STD-28-1 “Second Generation Cordless Telephone System Standard”, 4.1, (1/2 volume)

In the conventional LCCH configuration, the BCCH transmission cycle is 1200 ms, and the SCCH transmission / reception cycle is 300 ms.
Also, the BCCH transmission cycle is related to the quickness of supplementation of the base station device in the terminal device, and the SCCH transmission / reception cycle is related to the quickness of channel allocation.
In order to improve the response at the start of a call, it is desired that the acquisition of the base station apparatus is made faster and the channel assignment is made faster.
In order to speed up channel assignment, it is required to reduce the collision probability for a signal transmitted from a terminal device.

  This invention is made | formed in view of such a condition, and it aims at providing the technique which reduces the collision probability with respect to the signal transmitted from the terminal device.

In order to solve the above problems, a terminal device according to an aspect of the present invention includes a request unit that transmits a request signal to a base station device by random access to establish communication with the base station device, and a request unit And a communication unit that performs communication with the base station apparatus after receiving a response signal to the transmitted request signal.
The request unit generates a request signal by selecting at least one subcarrier among multicarrier signals formed by a plurality of subcarriers.

Another aspect of the present invention is a base station apparatus.
The apparatus includes: a response unit including a means for receiving a request signal by random access from the terminal apparatus and a means for transmitting a response signal to the received request signal in order to establish communication with the terminal apparatus; And a communication unit that performs communication with the terminal device after transmitting the response signal.
The response unit defines a signal in which at least one subcarrier is selected from among multicarrier signals formed by a plurality of subcarriers as a request signal. The terminal device to which the response signal is to be transmitted is determined based on the subcarrier used for the transmission.

  It should be noted that any combination of the above-described constituent elements and a conversion of the expression of the present invention between a method, an apparatus, a system, a recording medium, a computer program, etc. are also effective as an aspect of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the collision probability with respect to the signal transmitted from the terminal device can be reduced.

It is a figure which shows the structure of the logical control channel in the conventional 2nd generation cordless telephone system. It is a figure which shows the structure of the paging area which concerns on the 1st Embodiment of this invention. FIGS. 3A to 3C are diagrams showing the configuration of the logical control channel in the first embodiment of the present invention. It is a figure which shows the structure of the TDMA frame in Fig.3 (a)-(c). It is a figure which shows the structure of the OFDMA subchannel in FIG. It is a figure which shows the structure of the subchannel block in FIG. It is a figure which shows the structure of the mobile communication system which concerns on the 1st Embodiment of this invention. It is a figure which shows the structure of the base station apparatus of FIG. It is a figure which shows the message format of BCCH transmitted from the base station apparatus of FIG. It is a figure which shows the message format of PCH transmitted from the base station apparatus of FIG. FIGS. 11A and 11B are diagrams illustrating time charts of stepwise initial ranging in the communication system of FIG. It is a figure which shows the message format of IRCH transmitted from the base station apparatus of FIG. It is a figure which shows the message format of RCH transmitted from the base station apparatus of FIG. It is a figure which shows the message format of SCCH transmitted from the base station apparatus of FIG. FIGS. 15A to 15C are diagrams showing time charts of stepwise initial ranging using a plurality of TCHs in the communication system of FIG. 16A to 16C are diagrams showing time charts of stepwise initial ranging using one TCH in the communication system of FIG. It is a sequence diagram which shows the TCH synchronization establishment procedure in the communication system of FIG. It is a flowchart which shows the TCH synchronization establishment procedure in the base station apparatus of FIG. It is a flowchart which shows the TCH synchronization establishment procedure in the terminal device of FIG. It is a figure which shows the logical control channel structure in the 2nd Embodiment of this invention. It is a figure which shows the comparison result of 1st Embodiment of this invention, and 2nd Embodiment. It is a figure which shows the structure of the terminal device which concerns on the 3rd Embodiment of this invention. FIGS. 23A and 23B are diagrams for explaining the outline of the TCCH transmitted from the terminal apparatus of FIG. It is a flowchart which shows the procedure of the channel allocation process in the terminal device of FIG. It is a flowchart which shows the procedure of the channel allocation process by the base station apparatus in the 3rd Embodiment of this invention.

(First Embodiment) In the first embodiment of the present invention, a plurality of terminal devices are connected by a TDMA-TDD (Time Division Multiple Access-Time Division Duplex) system as in the second generation cordless telephone system. Base station apparatus.
FIG. 2 is a conceptual diagram of a paging area composed of a plurality of base station apparatuses.
FIG. 2 includes the first base station apparatus (shown as CS1 in the figure) to the eighth base station apparatus (shown as CS8 in the figure).
In FIG. 2, the service area formed by each base station apparatus is indicated by a solid oval.
FIG. 2 shows a paging area (indicated by PA1 in the figure) composed of the first base station apparatus to the fourth base station apparatus, and a paging area composed of the fifth base station apparatus to the eighth base station apparatus (see FIG. 2). Medium, PA2).
In the paging area, simultaneous calls are made for location registration.

FIG. 3 (a) is a diagram illustrating a configuration of an LCCH that is a logical control channel in the first embodiment of the present invention.
In the figure, “IRCH” is an initial ranging channel used at the time of channel assignment, and may be functionally a channel corresponding to “SCCH” in FIG.
More specifically, “TCCH” and “IRCH” are included in “IRCH” shown in FIG. 3A, and “TCCH” is transmitted from the terminal apparatus to the base station apparatus. Corresponds to the initial ranging requirement.
“IRCH” corresponds to a response to the initial ranging request.
Therefore, “TCCH” is an uplink signal, and “IRCH” is a downlink signal.
In addition, although the base station apparatus which received TCCH from a terminal device performs the ranging process, since the ranging process may be a well-known technique, description is abbreviate | omitted here.

One LCCH shown in FIG. 3A is composed of a total of 24 channels of 8 PCHs, 8 BCCHs, and 8 IRCHs.
The PCH is arranged in one TDMA frame (hereinafter referred to as “frame”), and the BCCH and IRCH are arranged in eight frames.
In FIG. 3A, for convenience, a frame in which PCH, BCCH, and IRCH are arranged is also indicated as “PCH”, “BCCH”, and “IRCH”.
As will be described later, a frame is divided into a plurality of time slots. Here, “PCH”, “BCCH” are used without distinguishing each of a time slot unit, a frame unit, and an 8-frame unit. ”And“ IRCH ”.
Also, terminal devices that are notified of incoming calls in eight PCHs included in one LCCH are generally different.

FIG. 3B shows the configuration of PCH.
FIG. 3 (b) shows the configuration of one frame, which is composed of eight time slots as shown.
Also, four uplink time slots are arranged in the first four, and four downlink time slots are arranged in the latter four.
In the figure, “PA1” represents that all base station apparatuses from the first base station apparatus to the fourth base station apparatus included in the corresponding paging area PA1 in FIG. 2 transmit PCH all at once.
That is, base station apparatuses included in the same paging area transmit PCHs having the same content in the same time slot.
Such a time slot is assumed to be predetermined.
Information included in the PCH will be described later.
The same applies to “PA2”.
As described above, since one frame includes four downlink time slots, a maximum of four paging areas are multiplexed by using different time slots.

FIG. 3C shows the configuration of BCCH and IRCH.
CS1 in FIG. 2 intermittently transmits BCCH and IRCH at intervals of 8 frames in the same time slot (indicated as CS1 in the figure) from the time slot where the PCH was transmitted.
CS2 belonging to the same paging area in FIG. 2 is the time slot (FIG. 2) where the position from the beginning of the frame is the same as the time slot in which the PCH is transmitted among the time slots in the next frame (second frame in the figure) transmitted by CS1. Middle, CS2), and BCCH and IRCH are intermittently transmitted at intervals of 8 frames.

Note that the base station apparatuses (CS4 to CS8 in FIG. 2) belonging to different paging areas are the next time slots used by the base station apparatus belonging to the paging area PA1 among the time slots constituting the frame. IRCH is transmitted intermittently.
That is, BCCH and IRCH are associated with each other.
With such a configuration, it is possible to multiplex up to four paging areas, eight base station apparatuses belonging to each paging area, and up to 32 base station apparatuses.
That is, as shown in FIG. 3B, when each time slot and the paging area are associated with each other, a plurality of base station apparatuses included in each paging area may follow the BCCH and the paging area in different frames. Send IRCH.
Here, the plurality of base station apparatuses included in the same paging area specify the frames to be used in the order of the identification numbers assigned to the respective base station apparatuses.

Further, as described above, the TCCH transmitted from the terminal apparatus to the base station apparatus is arranged in the uplink time slot in the frame in which the IRCH is arranged.
From the IRCH arrangement described above, the base station apparatus that is the destination of the TCCH is specified by the time slot.
For example, as shown in the figure, if the first downlink time slot is assigned to CS1 to transmit IRCH, the first uplink time slot indicated as “TCCH” A TCCH to CS1 is transmitted.

Comparing the LCCH shown in FIGS. 3A to 3C with the conventional LCCH shown in FIG. 1, the BCCH transmission cycle is 85 ms, and the time required for acquisition by the base station apparatus is shortened.
Further, the IRCH transmission / reception cycle is 85 ms, and the time required for channel allocation is also shortened.
For this reason, since the time required to start a call can be improved as compared with the conventional LCCH, the convenience of the user can be improved, and high-speed handover between base station apparatuses can be realized. Is possible.

FIG. 4 shows the structure of a TDMA frame.
In the communication system according to the first embodiment, as in the second-generation cordless telephone system, as shown in FIG. 4, four time slots for uplink communication (terminal device to base station device), downlink communication (base station device) To the terminal device), a frame is composed of four time slots, and the frames are continuously arranged.
Since uplink communication and downlink communication are symmetric in this embodiment, only downlink communication in which the transmission side is a base station apparatus and the reception side is a terminal apparatus will be described below for convenience of explanation.
The frame configuration shown in FIG. 4 corresponds to the frame configuration shown in FIGS.

In addition to the TDMA described so far, the base station apparatus also applies OFDMA (Orthogonal Frequency Division Multiple Access) as shown in FIG. 5, and assigns a plurality of terminal apparatuses to one time slot.
FIG. 5 shows the arrangement of time slots on the time axis in the direction of the horizontal axis, and the arrangement of subchannels on the frequency axis in the direction of the vertical axis.
That is, multiplexing on the horizontal axis corresponds to TDMA, and multiplexing on the vertical axis corresponds to OFDMA.
FIG. 5 includes the first time slot (shown as T1 in the figure) to the fourth time slot (shown as T4 in the figure) in one frame.
For example, T1 to T4 in FIG. 5 correspond to the fifth to eighth time slots in FIG. 4, respectively.

FIG. 5 includes the first subchannel (indicated as SC1 in the figure) to the 16th subchannel (indicated as SC16 in the figure) in each time slot.
In FIG. 5, the terminal device A is on the second subchannel of the first time slot, the terminal device B is on the second subchannel to the fourth subchannel of the second time slot, and the terminal device is on the 16th subchannel of the third time slot. C, and the terminal equipment D is assigned to the 13th to 15th subchannels of the fourth time slot.
In FIG. 5, the first subchannel is reserved as a control channel dedicated subchannel, and in the figure, the first base station apparatus uses the control channel assigned to the first subchannel of the first time slot.
That is, the frame configuration when focusing only on SC1 and a set of a plurality of frames correspond to the LCCH.

FIG. 6 is a conceptual diagram showing a configuration of a radio channel (hereinafter referred to as a subchannel block) specified by a time slot and a subchannel in FIG.
The horizontal direction in FIG. 6 is a time axis, and the vertical direction is a frequency axis.
The numbers “1” to “29” indicate subcarrier numbers.
In this way, the subchannel is configured by an OFDM multicarrier signal.
In the figure, “TS” corresponds to a training symbol and includes known signals such as a synchronization detection symbol “STS” (not shown) and a transmission path characteristic estimation symbol “LTS”.
“GS” corresponds to a guard symbol, and no effective signal is arranged here.
“PS” corresponds to a pilot symbol and is configured by a known signal.
“SS” corresponds to a signal symbol, and a control signal is arranged.
“DS” corresponds to a data symbol and is data to be transmitted.
“GT” corresponds to a guard time, and no effective signal is arranged.

FIG. 7 is a conceptual diagram showing the configuration of the mobile communication system 20 according to the first embodiment of the present invention.
The mobile communication system 20 includes a base station device 1 and a terminal device 2.
In FIG. 7, three terminals, ie, the first terminal apparatus 2a, the second terminal apparatus 2b, and the third terminal apparatus 2c, which are collectively referred to as the terminal apparatus 2, are illustrated, but there are two or less terminal apparatuses or four or more terminal apparatuses. May be.
Further, the base station apparatus 1 corresponds to one of the base station apparatuses shown in FIG.

FIG. 8 is a conceptual diagram showing the configuration of the base station apparatus 1 of FIG.
The base station apparatus 1 includes an antenna 100, a radio unit 101, a transmission unit 102, a modulation unit 103, a reception unit 104, a demodulation unit 105, an IF unit 106, and a control unit 107. The control unit 107 includes a ranging processing unit 110 and an allocation unit. Part 112 is included.
In FIG. 8, an antenna 100 transmits and receives radio frequency signals.
Here, the radio frequency signal corresponds to FIG. 4 to FIG. 6.
As a reception process, radio section 101 performs frequency conversion on a radio frequency signal received by antenna 100, derives a baseband signal, and outputs the baseband signal to reception section 104.
In addition, as a transmission process, the radio unit 101 performs frequency conversion on the baseband signal from the transmission unit 102, derives a radio frequency signal, and outputs the signal to the antenna 100.
Since a baseband signal is generally formed by an in-phase component and a quadrature component, two signal lines should be shown, but for the sake of clarity, only one signal line is shown here. It shall be shown.

The transmission unit 102 converts the frequency domain signal transmitted from the modulation unit 103 into a time domain signal and outputs the time domain signal to the radio unit 101.
In addition, IFFT (Inverted Fast Fourier Transform) is used for the conversion from the frequency domain signal to the time domain signal.
Modulation section 103 modulates the input from IF section 106 and outputs the result to transmission section 102.
As a modulation method, BPSK (Binary Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), 16QAM (Quadrature Amplitude Modulation), 32QAM, 64QAM, 256QAM, and the like are used.

The reception unit 104 converts the time domain signal transmitted from the radio unit 101 into a frequency domain signal and outputs the frequency domain signal to the demodulation unit 105.
Note that FFT (Fast Fourier Transform) is used for the conversion from the time domain signal to the frequency domain signal.
Demodulation section 105 demodulates the input from receiving section 104 and outputs the result to IF section 7.
Demodulation corresponds to modulation.
The IF unit 7 is connected to a network (not shown), and outputs a signal demodulated by the demodulation unit 105 to a network (not shown) as reception processing.
In addition, the IF unit 7 inputs data from the network and outputs it to the modulation unit 103 as transmission processing.

The control unit 107 controls the timing of the entire base station apparatus 1.
Moreover, the control part 107 comprises LCCH shown to Fig.3 (a), and transmits to the terminal device 2 intermittently.
In SC1 of FIG. 5, the ranging processing unit 110 notifies information related to the base station apparatus 1 after the PCH for notifying an incoming call to the terminal apparatus 2 (not shown) as shown in FIG. 3A. BCCH is arranged.
In addition, ranging processing section 110 arranges the timing for receiving TCCH, which is a ranging request from the terminal device, and the timing for transmitting IRCH corresponding to TCCH in the subsequent stage of BCCH.
In addition, the ranging processing unit 110 periodically uses a combination of the above PCH, BCCH, TCCH, and IRCH (hereinafter, the combination of TCCH and IRCH is also referred to as IRCH, but is used without distinction from the case of IRCH alone). One cycle of LCCH is formed by repeating the process.

Moreover, the ranging process part 110 alert | reports PCH at the same timing as the other base station apparatus 1 which is not shown in a simultaneous call area like FIG.3 (b).
Further, as shown in FIG. 3C, the ranging processing unit 110 performs BCCH notification, TCCH reception, and IRCH transmission at a time-division multiplexed timing with other base station apparatuses 1 in the simultaneous call area. .
That is, ranging processor 110 broadcasts PCH and BCH once in one combination, receives TCCH once, and transmits IRCH once.

FIG. 9 is a conceptual diagram of a BCCH message format.
The BCCH includes a message identifier for discriminating the type of message, and parameters defining the structure of the logical control channel, for example, LCCH structure information representing an interval value, incoming call grouping, a battery saving cycle maximum value, and the like.
FIG. 10 is a conceptual diagram of a PCH message format.
The PCH includes a message identifier for determining the type of message and the number of the terminal device that has received the incoming call.
When the terminal device 2 receives the notification that the incoming call is received by the PCH, the terminal device 2 makes an initial ranging request to the base station device 1 that has transmitted the PCH.
Returning to FIG.

When receiving the TCCH from the terminal device 2, the ranging processing unit 110 adjusts the transmission power and transmission timing of the terminal device 2 using a known technique.
In addition, the ranging processing unit 110 repeatedly executes a ranging response including the adjustment result, for example, a ranging process for transmitting IRCH a plurality of times.
In order to describe such processing in detail, FIGS. 11A to 11B are used here.
FIGS. 11A and 11B are time charts of stepwise initial ranging in the mobile communication system 20.
Here, for convenience of explanation, numbers are assigned to the frames in order from the front, and the frames 1 to 9 are indicated as “F1” to “F9”.
For the sake of clarity, only the first time slot of each of the uplink and the downlink is shown in each frame shown in FIG.

Here, as shown in FIG. 3C and FIG. 11A, the ranging processing unit 110 defines in advance the timing at which the TCCH from the terminal device 2 should be received for the first time.
That is, for each combination in FIGS. 3A to 3C, the timing at which TCCH should be received for the first time is defined as F1 in FIG. 11A so as to be associated with BCCH (not shown).
Further, the ranging processing unit 110 defines the timing at which IRCH should be transmitted by F1.
On the other hand, the timing at which CS2, which is a different base station apparatus 1, should receive the TCCH for the first time is defined as F2.
As a result, the terminal device 2 (not shown) can select the base station device 1 as the TCCH transmission destination by selecting F1 or F2.
In addition, the ranging processing unit 110 defines a frequency band in which PCH and BCCH are periodically assigned to each base station apparatus 1, that is, a timing to be received at the first TCCH and a timing to be transmitted to the IRCH in SC1 of FIG. To do.

A plurality of types of TCCH are defined as waveform patterns.
That is, a waveform pattern is defined by selecting a part of the plurality of subcarriers, and a plurality of types of waveform patterns are defined by changing the selected subcarrier.
Therefore, even when the ranging processing unit 110 receives TCCH from a plurality of terminal devices 2 at the same time, the ranging processing unit 110 can recognize the plurality of terminal devices 2 if the waveform patterns between them are different.
That is, the collision probability of TCCH is reduced.
In addition, the terminal device 2 (not shown) selects one of a plurality of types of waveform patterns as a TCCH transmission unit.
As a result, the TCCH transmitted from the same terminal device 2 may be different for each transmission.
Here, the terminal device 2 (not shown) randomly selects one of a plurality of types of waveform patterns.

FIG. 12 is a conceptual diagram of an IRCH message format that is a response to an initial ranging request.
The IRCH instructs to change the message identifier for determining the message type, information for identifying the transmission source that made the initial ranging request, and the identification information of the transmission source to a value different from that of the initial initial ranging request. It includes a transmission source identification information change instruction and information (slot number and subchannel number) specifying a data transfer channel (hereinafter referred to as TCH) to transmit the second TCCH.
Here, TCH corresponds to a subchannel other than CS1 in FIG.
In the latter part, the communication channel used for communication is also indicated as TCH, but these are used without distinction.
The transmission source identification information is such that even when there are simultaneous initial ranging requests from a plurality of terminal devices 2, the base station device 1 can identify the plurality of terminal devices 2 by performing a predetermined calculation on the transmission source identification information. , Is a predefined value.
Returning to FIG.

That is, the ranging processing unit 110 defines the timing at which the TCCH from the terminal device 2 is to be received after the second time, by the previous ranging response, for example, the IRCH.
In addition, the ranging processing unit 110 displays the timing and ranging response to receive the TCCH for the second and subsequent times in the frequency band in which the TCH is adaptively allocated to each base station apparatus 1, for example, SC2 to SC16 in FIG. It defines the timing to be transmitted after the second time.
FIG. 11B corresponds to a time chart in a subchannel specified by IRCH, and ranging processing section 110 receives TCCH in F3 and transmits RCH as a ranging response.

FIG. 13 is a conceptual diagram of a ranging channel (hereinafter, RCH) which is a response to the second initial ranging request.
The RCH includes a message identifier for determining the type of message, control information for matching synchronization (timing alignment control and transmission output control), and SCCH transmission / reception timing indicating the start time of the radio resource allocation request.
The terminal apparatus 2 makes a radio resource allocation request after establishing synchronization with the base station apparatus 1 by correcting a time lag by timing alignment control and transmission power by transmission output control.
Returning to FIG.

As shown in FIG. 11B, it is assumed that SCCHs in F5 and F6 are designated in RCH.
When receiving the SCCH from the terminal device 2 (not shown) after the ranging process in the ranging processing unit 110 is completed, the allocating unit 112 in FIG. 8 allocates a communication channel TCH to the terminal device 2.
The allocation unit 112 transmits the allocation result included in the SCCH in F6 of FIG.
As described above, the allocation unit 112 performs the channel allocation process for the terminal device 2 that has transmitted the IRCH in a frequency band different from the frequency band in which the BCCH, PCH, and the like are arranged in the ranging processing unit 110.

FIG. 14 is a conceptual diagram of an SCCH message format that is a response to a radio resource allocation request.
The SCCH includes a message identifier for determining a message type, a service flow identifier assigned to the terminal device 2, and information (slot number and subchannel number) specifying the TCH assigned to the terminal device 2.
When trying to perform initial ranging and channel allocation using the conventional LCCH shown in FIG. 1, another base station apparatus that requested the initial ranging by the terminal apparatus makes an initial ranging response, or the initial ranging operation and other base station apparatuses In this embodiment, the initial ranging request is processed in stages, the LCCH responds until the first initial ranging request response, and the second initial ranging request thereafter. The radio resource allocation is made to respond with TCH.
Accordingly, channel assignment can be performed for a plurality of terminal devices at a time, and the terminal devices can be accurately separated without preparing a large number of transmission source identification information.
Returning to FIG.
As shown in FIG. 11B, it is assumed that the TCH after F8 is designated in the SCCH.
The control unit 107 communicates with the terminal device 2 after the allocation of the TCH in the allocation unit 112.

Returning to FIG.
The ranging processing unit 110 recognizes the presence of two or more terminal devices 2 when receiving at least two or more types of waveform patterns at a timing at which TCCH should be received.
When the ranging processing unit 110 recognizes the presence of two or more terminal devices 2, the ranging processing unit 110 allocates different frequency bands, that is, different subchannels, to each of the two or more terminal devices 2.
The ranging processing unit 110 transmits information on the assigned subchannel included in the IRCH.
When the ranging processing unit 110 recognizes the presence of two or more terminal devices 2, the ranging processing unit 110 adjusts transmission power and the like for each.

Subsequent processing is performed in parallel in another subchannel.
That is, the allocating unit 112 performs a process for allocating a channel to each of two or more terminal devices 2 using the subchannel allocated by the ranging processing unit 110.
The assigning unit 112 assigns another TCH to each of the two or more terminal devices 2 recognized by the ranging processing unit 110.
The control unit 107 communicates with each of two or more terminal devices 2 to which another TCH is assigned.

FIG. 15 is a timing chart of the stepwise initial ranging process in the present embodiment.
In the figure, F1 to F9 represent one frame period.
TCCH is an initial ranging request including a message identifier and transmission source identification information.
Hereinafter, stepwise initial ranging processing and channel assignment processing will be described with reference to FIG.
The terminal device PS1 stores the transmission source identification information UID “1” in the TCCH, the terminal device PS2 stores the transmission source identification information UID “2”, and transmits it to the base station device CS1 in the upstream period of the frame F1. Make a request.
The base station apparatus CS1 performs a predetermined calculation on the transmission source identification information UID of the superimposed terminal apparatus PS1 and the transmission source identification information UID of the terminal apparatus PS2 to separate them, and communicates with the terminal apparatus PS1 from among the vacant TCHs. Channel 1 is assigned to terminal device PS2 and communication channel 2 is assigned.
Then, the slot number and subchannel number of the allocated TCH are stored in the IRCH, and transmitted to the terminal device PS1 and the terminal device PS2 in the downlink period of the frame F1.

Hereinafter, since the operation of the terminal device PS1 and the terminal device PS2 is the same, the terminal device PS1 will be described as an example.
In order to avoid a collision with the logical control channel of another base station apparatus, the terminal apparatus PS1 stands by in the frame F2.
The terminal apparatus PS1 stores the transmission source identification information UID “1” in the TCCH, and transmits it to the base station apparatus CS1 in the uplink period of the frame F3 using the allocated communication channel 1, and sends a second initial ranging request. Do.
The base station apparatus CS1 performs a ranging process using the communication channel 1, stores time alignment control, transmission output control, and SCCH transmission / reception timing in the RCH, and transmits them to the terminal apparatus PS1 in the downlink period of the frame F3. .
In order to avoid a collision with an initial ranging request for another base station apparatus, the terminal apparatus PS1 stands by in a frame F4.
The terminal device PS1 uses the communication channel 1 to make a radio resource allocation request to the base station device CS1 during the uplink period of the frame F5.

The base station apparatus CS1 performs FEC (Forward Error Collection) decoding processing on the radio resource allocation request message from the terminal apparatus PS1, and then allocates a free TCH to the terminal apparatus PS1.
Since the FEC decoding process takes time, the slot number and subchannel number of the allocated TCH are stored in the SCCH and transmitted to the terminal apparatus PS1 during the downlink period of the frame F6.
If the FEC decoding process can be speeded up, the SCCH may be transmitted to the terminal apparatus PS1 during the downlink period of the frame F5.
When time is required for the FEC processing of the base station apparatus CS1, the terminal apparatus PS1 may repeat the radio resource allocation request for the base station apparatus CS1 during the uplink period of the frame F5 during the uplink period of the frame F6.
This is because, when the base station apparatus CS1 is performing adaptive array processing, the calculation accuracy of the weight vector can be improved.
The terminal apparatus PS1 performs FEC decoding processing on the SCCH from the base station apparatus CS1, and establishes synchronization with the base station apparatus CS1 using the frame F8.
Thereafter, data is transmitted / received to / from the base station apparatus CS1 using the TCH having established synchronization.

As described above, when there is an initial ranging request from a plurality of terminal devices 2, a vacant TCH is assigned to each terminal device 2, and the second initial ranging processing is performed. It is also conceivable to realize with one TCH.
Returning to FIG.

When the ranging processing unit 110 recognizes the presence of two or more terminal devices 2, the ranging processing unit 110 may assign different timings in the same subchannel to each of the two or more terminal devices 2.
That is, TCCH and RCH in each of the two or more terminal devices 2 are arranged in different frames.
The allocating unit 112 executes a process for allocating a channel to each of the two or more terminal devices 2 at the timing allocated by the ranging processing unit 110.
For example, after TCCH, RCH, and SCCH for PS1 (not shown) are arranged, TCCH, RCH, and SCCH for PS2 (not shown) are arranged.

FIG. 16 is a timing chart of the stepwise initial ranging process performed with one TCH.
Hereinafter, stepwise initial ranging processing and channel assignment processing performed on one TCH will be described with reference to FIG.
The terminal device PS1 stores the transmission source identification information UID “1” in the TCCH, the terminal device PS2 stores the transmission source identification information UID “1”, and transmits it to the base station device CS1 during the upstream period of the frame F1. Make a request.
The base station apparatus CS1 performs a predetermined operation on the superimposed transmission source identification information UID of the terminal apparatus PS1 and transmission source identification information UID of the terminal apparatus PS2.
However, these UIDs are the same and cannot be separated.
The base station apparatus CS1 allocates the communication channel 1 to the terminal apparatus PS1 and the terminal apparatus PS2 from the vacant TCHs.
The slot number and subchannel number of the allocated TCH are stored in the IRCH, and the change of the transmission source identification information is instructed, and transmitted to the terminal device PS1 and the terminal device PS2 during the downlink period of the frame F1.

In order to avoid collision with the logical control channel of the other base station apparatus, the terminal apparatus PS1 and the terminal apparatus PS2 stand by in the frame F2.
The terminal apparatus PS1 stores the transmission source identification information UID “1” in the TCCH, and transmits it to the base station apparatus CS1 in the uplink period of the frame F3 using the allocated communication channel 1, and sends a second initial ranging request. Do.
On the other hand, the terminal device PS2 that has received the instruction to change the transmission source identification information stores the transmission source identification information UID “2” in the TCCH, and uses the assigned communication channel 1 to transmit the base station device in the uplink period of the frame F3. Send to CS1 and make a second initial ranging request.

The base station apparatus CS1 performs a predetermined operation on the superimposed transmission source identification information UID of the terminal apparatus PS1 and transmission source identification information UID of the terminal apparatus PS2 to separate them.
Then, ranging processing is performed using the communication channel 1, time alignment control, transmission output control, and SCCH transmission / reception timing are stored in the RCH, and transmitted to the terminal device PS1 in the downlink period of the frame F3.
Here, the SCCH transmission / reception timing is designated as “T5” as the start timing.
Similarly, ranging processing is performed using the communication channel 2, time alignment control, transmission output control, and SCCH transmission / reception timing are stored in the RCH, and transmitted to the terminal apparatus PS2 in the downlink period of the frame F3.
Here, the SCCH transmission / reception timing is designated as “F7” as the start timing.
In order to avoid a collision with an initial ranging request for another base station apparatus, the terminal apparatus PS1 and the terminal apparatus PS2 wait in a frame F4.

The terminal device PS1 uses the communication channel 1 to make a radio resource allocation request to the base station device CS1 during the uplink period of the frame F5.
The base station apparatus CS1 performs FEC decoding processing on the radio resource allocation request message from the terminal apparatus PS1, and then allocates the communication channel 2 from the vacant TCH to the terminal apparatus PS1.
Since the FEC decoding process takes time, the slot number and subchannel number of the allocated TCH are stored in the SCCH and transmitted to the terminal apparatus PS1 during the downlink period of the frame F6.
If the FEC decoding process can be speeded up, the SCCH may be transmitted to the terminal apparatus PS1 during the downlink period of the frame F5.

When time is required for the FEC processing of the base station apparatus CS1, the terminal apparatus PS1 may repeat the radio resource allocation request for the base station apparatus CS1 during the uplink period of the frame F5 during the uplink period of the frame F6.
This is because, when the base station apparatus CS1 is performing adaptive array processing, the calculation accuracy of the weight vector can be improved.
The terminal apparatus PS1 performs FEC decoding processing on the SCCH from the base station apparatus CS1, and establishes synchronization with the base station apparatus CS1 using the frame F8.
Thereafter, data is transmitted / received to / from the base station apparatus CS1 using the TCH having established synchronization.

On the other hand, the terminal device PS2 uses the communication channel 1 to make a radio resource allocation request to the base station device CS1 during the uplink period of the frame F7.
The base station apparatus CS1 performs an FEC decoding process on the radio resource allocation request message from the terminal apparatus PS2, and then allocates a free TCH to the terminal apparatus PS2.
Since time is required for the FEC decoding process, the slot number and subchannel number of the allocated TCH are stored in the SCCH and transmitted to the terminal apparatus PS2 in the downlink period of the frame F8.
If the FEC decoding process can be speeded up, the SCCH may be transmitted to the terminal apparatus PS2 during the downlink period of the frame F7.

When time is required for the FEC processing of the base station apparatus CS1, the terminal apparatus PS2 may repeat the radio resource allocation request for the base station apparatus CS1 during the uplink period of the frame F8 during the uplink period of the frame F8.
This is because, when the base station apparatus CS1 is performing adaptive array processing, the calculation accuracy of the weight vector can be improved.
The terminal apparatus PS2 performs FEC decoding processing on the SCCH from the base station apparatus CS1, and establishes synchronization with the base station apparatus CS1 with the frame F9.
Thereafter, data is transmitted / received to / from the base station apparatus CS1 using the TCH having established synchronization.

This configuration can be realized in terms of hardware by a CPU, memory, or other LSI of any computer, and in terms of software, it is realized by a program having a communication function loaded in the memory. Describes functional blocks realized by collaboration.
Accordingly, those skilled in the art will understand that these functional blocks can be realized in various forms by hardware only, software only, or a combination thereof.

The operation of the mobile communication system 20 having the above configuration will be described.
FIG. 17 is a sequence diagram showing establishment of TCH synchronization in the mobile communication system 20.
The base station device 1 stores the terminal number of the terminal device 2, and transmits the PCH simultaneously with other base station devices belonging to the paging area (S100).
The base station apparatus 1 transmits BCCH at a predetermined timing (S102).
If the terminal device 2 that has received the PCH includes its own terminal number in the PCH, the base station device 1 is identified based on the BCCH, and then the source identification information is stored in the TCCH, and the base station device CS1 To the initial initial ranging request (S104).
The base station apparatus CS1 separates the transmission source identification information UID of the terminal apparatus 2 from the received TCCH, and allocates the terminal apparatus 2 to an empty TCH.
Then, the slot number and subchannel number of the allocated TCH are stored in the IRCH and transmitted to the terminal device 2, and the TCH for the second initial ranging is notified to the terminal device 2 (S106).
The terminal device 2 stores the transmission source identification information in the TCCH, transmits it to the base station device 1 using the allocated initial ranging TCH, and makes a second initial ranging request (S108).

The base station apparatus 1 performs a ranging process using the TCH allocated to the terminal apparatus 2, stores time alignment control, transmission output control, and SCCH transmission / reception timing in the RCH, and transmits to the terminal apparatus 2 for transmission. Request correction of output or the like (S110).
The terminal device 2 extracts the correction value requested from the base station device 1 from the received RCH, and corrects the transmission output and the like.
Next, a radio resource allocation request is made to the base station apparatus 1 using the allocated initial ranging TCH (S112).
The base station apparatus 1 performs an FEC decoding process on the radio resource allocation request message from the terminal apparatus PS1, and then allocates a free TCH to the terminal apparatus 2.
Then, the slot number and subchannel number of the allocated TCH are stored in the SCCH and transmitted to the terminal device 2 (S114).
Since the TCH synchronization is established through the steps up to here, the base station apparatus 1 and the terminal apparatus 2 transmit and receive data using the synchronized TCH (S116).

FIG. 18 is a flowchart showing a TCH synchronization establishment procedure in the base station apparatus 1.
If the ranging processing unit 110 does not receive the TCCH via the reception unit 104 and the demodulation unit 105 (N in S10), it stands by.
When the TCCH is received (Y in S10), if the TCCH is not a plurality of types of waveform patterns (N in S12), the ranging processing unit 110 designates the frequency band and timing by IRCH (S14).
The ranging processing unit 110 transmits the IRCH via the modulation unit 103 and the transmission unit 102.
If the TCCH received again via the receiving unit 104 and the demodulating unit 105 is not a plurality of types of waveform patterns (N in S16), the ranging processing unit 110 designates the SCCH transmission / reception timing using the RCH (S18).
The ranging processing unit 110 transmits the RCH via the modulation unit 103 and the transmission unit 102.
Further, when receiving the SCCH via the receiving unit 104 and the demodulating unit 105, the allocating unit 112 performs channel allocation by the SCCH (S20), and the allocation result is sent to the SCCH via the modulating unit 103 and the transmitting unit 102. Send as.
Thereafter, the base station device 1 communicates with the terminal device 2 by TCH (S22).

On the other hand, if the TCCH received again via the receiving unit 104 and the demodulating unit 105 is a plurality of types of waveform patterns (Y in S16), the ranging processing unit 110 performs time-division of the SCCH for each received waveform pattern. Transmission / reception timing is designated by RCH (S24).
The ranging processing unit 110 transmits the RCH via the modulation unit 103 and the transmission unit 102.
Further, when receiving the SCCH via the receiving unit 104 and the demodulating unit 105, the allocating unit 112 performs channel allocation by SCCH (S26), and the allocation result is sent to the SCCH via the modulating unit 103 and the transmitting unit 102. Send as.
Note that the above-described channel assignment by SCCH is performed a plurality of times while time-sharing according to the number of terminal apparatuses 2.
As a result, a channel is assigned to each of the plurality of terminal devices 2.
Thereafter, the base station device 1 communicates with each of the plurality of terminal devices 2 by TCH (S28).

If the TCCH is a plurality of types of waveform patterns (Y in S12), the ranging processing unit 110 designates a different frequency band by IRCH for each received waveform pattern (S30).
The ranging processing unit 110 transmits the IRCH via the modulation unit 103 and the transmission unit 102.
If the TCCH received again in each frequency band via the receiving unit 104 and the demodulating unit 105 is not a plurality of types of waveform patterns (N in S32), the ranging processing unit 110 designates the SCCH transmission / reception timing by the RCH. (S34).
The ranging processing unit 110 transmits the RCH via the modulation unit 103 and the transmission unit 102.
Further, when receiving the SCCH via the receiving unit 104 and the demodulating unit 105, the allocating unit 112 performs channel allocation by the SCCH (S36), and the allocation result is sent to the SCCH via the modulating unit 103 and the transmitting unit 102. Send as.
Thereafter, the base station device 1 communicates with each of the plurality of terminal devices 2 by TCH (S38).
Steps 32 to 36 are performed in parallel in a plurality of frequency bands.

On the other hand, if the TCCH received again via the receiving unit 104 and the demodulating unit 105 is a plurality of types of waveform patterns (Y in S32), the ranging processing unit 110 performs the time-division of the SCCH for each received waveform pattern. Transmission / reception timing is designated by RCH (S40).
The ranging processing unit 110 transmits the RCH via the modulation unit 103 and the transmission unit 102.
Further, when receiving the SCCH via the receiving unit 104 and the demodulating unit 105, the allocating unit 112 performs channel allocation by SCCH (S42), and the allocation result is transmitted to the SCCH via the modulating unit 103 and the transmitting unit 102. Send as.
Note that the above-described channel assignment by SCCH is performed a plurality of times while time-sharing according to the number of terminal apparatuses 2.
As a result, a channel is assigned to each of the plurality of terminal devices 2.
Thereafter, the base station device 1 communicates with each of the plurality of terminal devices 2 by TCH (S44).
That is, step 40 and step 42 are performed by time division in each of a plurality of frequency bands.

FIG. 19 is a flowchart showing a TCH synchronization establishment procedure in the terminal device 2.
If the terminal device 2 does not recognize the incoming call on the PCH (N in S50), the terminal device 2 stands by.
If the incoming call is recognized on the PCH (Y in S50), the terminal device 2 specifies the base station device 1 on the BCCH (S52).
The terminal device 2 transmits TCCH to the identified base station device 1 (S54).
The terminal device 2 receives the IRCH from the base station device 1 (S56).
The terminal device 2 changes the TCCH pattern (S58), and transmits the TCCH to the base station device 1 (S60).
After the terminal device 2 receives the RCH from the base station device 1 (S62), the channel assignment by SCCH is performed (S64).
Thereafter, the terminal device 2 communicates with the base station device 1 by TCH (S66).

According to such an embodiment of the present invention, the following operational effects can be enjoyed.
(1) The control unit 107 transmits PCH simultaneously with base station apparatuses belonging to the same paging area, and individually transmits BCCH and IRCH at different transmission timings from base station apparatuses belonging to the same paging area to form an LCCH. Therefore, it is possible to shorten the time required for capturing the base station apparatus as compared with the conventional LCCH.

(2) When there is an initial initial ranging request from a plurality of terminal devices 2, the control unit 107 allocates a vacant TCH for each terminal device 2, and assigns the second initial ranging process and channel allocation process to the allocated TCH. Therefore, channel allocation can be performed for a plurality of terminal devices at a time.
(3) When there is an initial initial ranging request from a plurality of terminal devices 2, the control unit 107 allocates one vacant TCH to the plurality of terminal devices 2 and performs the second initial ranging process and channel allocation process. Since the allocated TCH is used, channel allocation can be performed for a plurality of terminal apparatuses at one time.

In addition, since the first TCCH and IRCH are arranged in a frequency band in which periodic signals such as BCCH and PCH are allocated and a plurality of base station apparatuses are time-division multiplexed, Collisions with TCHs of other base station apparatuses can be avoided.
In addition, with the above arrangement, the dedicated subchannel for initial ranging can be omitted.
In addition, since the dedicated subchannel for initial ranging is omitted, transmission efficiency can be improved.
In addition, since the timing at which the first TCCH should be allocated is associated with the BCCH transmission timing, the TCCH can be transmitted while identifying the base station apparatus as the transmission destination.
In addition, since the TCCH is transmitted while specifying the base station apparatus that is the transmission destination, it is possible to avoid the TCCH reception process by a plurality of base station apparatuses.

In addition, since a plurality of ranging processes are executed in stages, it is possible to cope with TCCH multiplexing processes.
In addition, since a plurality of ranging processes are executed in stages, channels can be allocated to a plurality of terminal devices.
In addition, since channel assignment processing is scheduled by time division multiplexing, channels can be assigned to a plurality of terminal apparatuses.
In addition, since channel allocation processing is scheduled by time division multiplexing, adaptive array transmission can be executed.

Second Embodiment In the first embodiment, the LCCH shown in FIG. 3 is configured, and the control unit 107 intermittently transmits the configured LCCH to the terminal device 2.
The LCCH shown in FIG. 3 has a shorter time required for acquisition by the base station apparatus than a conventional LCCH and a required time for channel allocation, but the number of paging areas that can be superimposed is limited. is there.
Considering that it is a base station device for replacing the existing second generation cordless telephone system, there is a case where it is not desired to limit the number of paging areas.
Therefore, in the second embodiment, an LCCH that is not subject to the limitation of the number of paging areas is configured.
That is, the second embodiment relates to a communication system and a base station apparatus that transmit a different type of LCCH than the first embodiment.
However, the configuration of the mobile communication system 20 according to the second embodiment is the same type as that in FIG. 7, and the configuration of the mobile communication system 20 according to the second embodiment is the same as that in FIG. Type.
Therefore, here, the description will focus on the parts different from these.

The ranging processing unit 110 arranges the timing for receiving the TCCH from the terminal device 2 (not shown) and the timing for transmitting the IRCH between the periodically arranged broadcast signals in SC1 of FIG. To do.
Here, as described above, either BCCH or PCH is arranged as the notification signal.
For example, a combination of BCCH, PCH, and PCH is repeatedly arranged.
At this time, an uplink TCCH and a downlink IRCH are arranged in pairs between BCCH and PCH, between PCH and PCH, and between PCH and BCCH.
Under such an LCCH configuration, processing for connection between the terminal apparatus 2 and the base station apparatus 1 is the same as before.

When receiving the TCCH from the terminal device 2 that has received the BCCH, the ranging processing unit 110 adjusts the transmission power and transmits the IRCH.
At that time, the ranging processing unit 110 specifies a subchannel different from SC1.
The ranging processing unit 110 performs channel assignment processing for the terminal device 2 by arranging SCCH in a frequency band different from the frequency band in which BCCH, PCH, the first TCCH, and IRCH are arranged.
Thereafter, the control unit 107 communicates with the terminal device 2 using the TCH.

FIG. 20 is a diagram illustrating a configuration of the LCCH in the second embodiment of the present invention.
As shown in FIG. 20, the logical control channel is composed of a total of 24 channels of 4 BCCHs, 12 IRCHs, and 8 PCHs.
BCCH, IRCH and PCH are composed of 8 frames.
As described above, IRCH includes uplink TCCH and downlink IRCH.
CS1 in FIG. 2 intermittently transmits BCCH, IRCH, and PCH at intervals of 8 frames in a time slot (designated as CS1 in the figure) to which a logical control channel is allocated among time slots constituting a frame.
2 is the same as the time slot used by the base station apparatus 1 in the time slot of the next frame (second frame in the figure) transmitted by the base station apparatus 1. BCCH, IRCH, and PCH are transmitted intermittently at intervals of 8 frames in a slot (indicated as CS2 in the figure).
With such a configuration, it is possible to multiplex up to eight base station apparatuses and a maximum of 32 base station apparatuses for every four downlink time slots constituting the frame.

FIG. 21 shows a comparison result between the first embodiment and the second embodiment of the present invention.
Here, the current second generation cordless telephone system, the second embodiment, and the first embodiment are compared.
The LCCH period, transmission period, BCCH transmission period, PCH reception period, and SCCH / IRCH transmission / reception period are “1200 ms”, “100 ms”, “1200 ms”, “1200 ms”, “300 ms” in the second generation coatless telephone system. "
On the other hand, they are “960 ms”, “40 ms”, “240 ms”, “960 ms”, “80 ms” in the second embodiment, and “680 ms”, “85 ms” in the first embodiment. , “85 ms”, “680 ms”, and “85 ms”.

Among these, if the BCCH transmission period is shortened, the base station supplement time can be shortened.
Further, the PCH incoming response time can be shortened by the shortness and arrangement of the BCCH transmission period, PCH reception period, and SCCH / IRCH transmission / reception period.
As a result, the base station supplement time and PCH incoming response time are “1200 ms” and “100-500 ms” in the second generation cordless telephone system.
On the other hand, they are “960 ms” and “40 ms” in the second embodiment, and “85 ms” and “45-85 ms” in the first embodiment.
That is, the base station supplement time and PCH incoming response time in the first and second embodiments are shortened compared to the values in the second generation cordless telephone system.
This can be said to be an improvement in responsiveness.

When the LCCH shown in FIG. 20 is compared with the conventional LCCH shown in FIG. 1, the BCCH transmission period is 240 ms, and the time required for acquisition by the base station apparatus is shortened.
Further, the IRCH transmission / reception cycle is 80 ms, and the time required for channel allocation is also shortened.
For this reason, compared with the conventional LCCH, the time required to start a call can be improved.
Further, when the LCCH shown in FIG. 20 is compared with the LCCH shown in FIG. 3, the time required for acquisition by the base station apparatus is shorter in the LCCH shown in FIG. 3, but the time required for channel allocation is shown in FIG. LCCH is advantageous in that it is shorter and improves the time required for channel assignment.
In FIG. 3, the position of the time slot to be used is determined for each paging area. However, in FIG. 20, there is no such limitation, and it is advantageous when it is not desired to limit the number of paging areas.

According to such an embodiment of the present invention, the following operational effects can be enjoyed.
(4) The control unit 107 transmits every other SCCH, and at the timing when the SCCH is not transmitted, repeats transmission in the order of BCCH, PCH, and PCH to configure the LCCH, and therefore requires more channel allocation than the conventional LCCH. Time can be shortened.

Further, since the first TCCH and IRCH are arranged between broadcast signals such as BCCH and PCH, the transmission / reception interval of the first TCCH and IRCH can be shortened.
In addition, since the transmission / reception interval of the first TCCH or IRCH is shortened, it is possible to shorten the period from when an incoming call is recognized by PCH until communication is made.
In addition, since the period from when the incoming call is recognized by the PCH to when it is communicated is shortened, the response to the incoming call can be improved.
Moreover, since the transmission / reception interval of the first TCCH or IRCH is shortened, channel allocation can be speeded up.

(Third Embodiment) In the first and second embodiments thus far, the TCCH transmitted from the terminal device 2 to the base station device 1 is defined as a waveform pattern.
A plurality of TCCH waveform patterns are defined.
Further, the base station apparatus 1 that has received the TCCH transmits an IRCH to the terminal apparatus 2.
In the third embodiment, a TCCH configuration, a TCCH selection procedure, and a TCCH reception process in the base station apparatus 1 will be specifically described.
Here, the TCCH is defined such that at least one subcarrier of the OFDM signal is selected.

Further, when the terminal device 2 newly transmits a TCCH, the terminal device 2 selects and transmits a TCCH with a small number of subcarriers used, and the number of subcarriers increases stepwise when no IRCH is received for the TCCH. TCCH is selected and transmitted.
On the other hand, the base station apparatus 1 prescribes | regulates the pattern with high selection priority among TCCH prescribed | regulated multiple types.
In particular, a priority is defined such that the higher the number of subcarriers used in TCCH, the higher the priority.
Such a regulation makes it easy to transmit IRCH for a TCCH having a large number of retransmissions, and an increase in the number of TCCH retransmissions is suppressed.

The configuration of the mobile communication system 20 according to the third embodiment of the present invention is the same type as that of the mobile communication system 20 shown in FIG.
FIG. 22 shows the configuration of the terminal device 2 according to the third embodiment of the present invention.
The terminal device 2 includes an antenna 200, a radio unit 202, a transmission / reception unit 204, a modem unit 206, an IF unit 208, and a control unit 210.
The control unit 210 includes a pattern determination unit 212.

The antenna 200 corresponds to the antenna 100 in FIG. 8, the radio unit 202 corresponds to the radio unit 101 in FIG. 8, the transmission / reception unit 204 corresponds to the transmission unit 102 and the reception unit 104 in FIG. Corresponds to the modulation unit 103 and the demodulation unit 105 in FIG. 8, and the IF unit 208 corresponds to the IF unit 106 in FIG.
Therefore, these descriptions are omitted.
The control unit 210 controls the operation of the terminal device 2.
Here, in particular, the description will focus on TCCH transmission performed for establishing communication with base station apparatus 1.
A signal transmitted from the terminal apparatus 2, that is, a signal transmitted from the modem unit 206, the transmission / reception unit 204, the radio unit 202, and the antenna 200 is an OFDM signal as described above, and includes a plurality of subcarriers.

On the other hand, TCCH is configured by selecting at least one subcarrier among multicarrier signals formed by a plurality of subcarriers.
In addition, there are a plurality of types of subcarriers selected for TCCH, and there are a plurality of types of subcarrier patterns to be selected for the same number of subcarriers.
In addition, when the subcarrier used differs, generally the pattern of a waveform will also differ.
As a result, it can be said that a plurality of waveform patterns are defined as TCCH.
Note that the control unit 210 acquires the timing at which the TCCH should be transmitted by receiving BCCH or the like via the antenna 200, the radio unit 202, the transmission / reception unit 204, and the modulation / demodulation unit 206.

However, the timing is not exclusively assigned to one terminal device 2.
For this reason, there is a possibility that the TCCH is transmitted from other terminal apparatuses 2 at the same timing.
That is, TCCH is transmitted to base station apparatus 1 by random access.
At this time, if the used subcarriers are different or if there is little overlap between the used subcarriers, collision between the transmission timings of a plurality of TCCHs is avoided. .
The pattern determination unit 212 of the control unit 210 selects a waveform pattern used for TCCH from a plurality of waveform patterns defined in advance.

FIGS. 23A and 23B are diagrams for explaining an overview of the TCCH transmitted from the terminal device 2. FIG.
23A to 23B show TCCH subcarriers transmitted from different terminal apparatuses 2 at the same transmission timing, or TCCH subcarriers transmitted from the same terminal apparatus 2 at different transmission timings. Show.
Here, in order to simplify the description, the number of subcarriers forming the OFDM signal is “7”.
23 (a)-(b) are shown corresponding to FIG.
Here, in the case of FIG. 23A, the subcarrier numbers “1”, “2”, “6”, and “7” are used. In the case of FIG. Subcarriers “2” and “5” are used.

When the TCCH shown in FIG. 23 (a) and the TCCH shown in FIG. 23 (b) are transmitted at the same transmission timing, the subcarrier of the subcarrier number “2” overlaps.
However, since the other subcarriers are different, both can be identified.
In particular, since there are three non-overlapping subcarriers in the TCCH in FIG. 23 (a), there is a high possibility that there will be no overlapping even if there are other TCCHs.
Returning to FIG.

When the TCCH is transmitted for the first time, the pattern determination unit 212 selects a pattern with a small number of subcarriers used from among a plurality of types of waveform patterns defined.
Further, after transmitting the TCCH of the selected pattern via the modem unit 206, the transmitting / receiving unit 204, the radio unit 202, and the antenna 200, the pattern determining unit 212 determines the number of subcarriers if it does not receive an IRCH for the TCCH. Select the pattern again while increasing.
Further, the pattern determination unit 212 increases the number of subcarriers step by step until the IRCH is received until the IRCH is received.
When the number of subcarriers becomes maximum, pattern determination unit 212 changes the type of pattern.
On the other hand, if the IRCH is received, the control unit 210 proceeds to the next step for channel allocation, which is the same as in the first embodiment or the second embodiment. The description is omitted.
Finally, the IF unit 208 from the antenna 200 performs communication with the base station apparatus 1.

The configuration of the base station apparatus 1 according to the third embodiment of the present invention is the same type as that of the base station apparatus 1 shown in FIG.
Here, the description will focus on the parts different from FIG.
The ranging processing unit 110 receives the TCCH from the terminal device 2 via the antenna 100, the radio unit 101, the receiving unit 104, and the demodulating unit 105.
Here, as described above, the ranging processing unit 110 defines a plurality of types of waveform patterns as TCCH.
In addition, the ranging processing unit 110 increases the priority of a predetermined pattern among a plurality of types of waveform patterns.
For example, the ranging processing unit 110 sets a higher priority for a TCCH with a larger number of subcarriers being used.

Therefore, when a plurality of TCCHs are received, the terminal device 2 that should transmit the IRCH is determined for the TCCH having a high priority, that is, based on the subcarrier used for the TCCH.
Here, the ranging processing unit 110 may calculate a correlation value between a pattern for a high-priority TCCH and a received signal and select a TCCH having a high correlation value.
In addition, the ranging processing unit 110 transmits the IRCH to the determined terminal device 2 via the modulation unit 103, the transmission unit 102, the wireless unit 101, and the antenna 100.
Since the subsequent processing is the same as that in the first embodiment or the second embodiment, description thereof is omitted here.
Finally, the base station device 1 executes communication with the terminal device 2.

FIG. 24 is a flowchart illustrating a procedure of channel assignment processing in the terminal device 2.
The pattern determination unit 212 selects the TCCH with the smallest number of subcarriers (S200).
The modem unit 206, the transmission / reception unit 204, the radio unit 202, and the antenna 200 transmit TCCH (S202).
If control unit 210 does not receive IRCH for TCCH via antenna 200, radio unit 202, transmission / reception unit 204, and modulation / demodulation unit 206 (N in S204), pattern determination unit 212 can increase the number of subcarriers. (Y in S206), the number of subcarriers is increased (S208), and a pattern is selected (S210).
On the other hand, if the number of subcarriers cannot be increased (N in S206), pattern determination unit 212 skips step 208 and executes step 210.
After step 210, the process returns to step 202.
When the control unit 210 receives the IRCH for the TCCH via the antenna 200, the radio unit 202, the transmission / reception unit 204, and the modulation / demodulation unit 206 (Y in S204), the allocation process is continued (S212).

FIG. 25 is a flowchart illustrating a procedure of channel assignment processing by the base station apparatus 1 according to the third embodiment of the present invention.
The ranging processor 110 receives a plurality of TCCHs via the antenna 100, the receiver 104, and the demodulator 105 (S220).
The ranging processing unit 110 calculates a correlation value between the received TCCH and a high priority pattern, and selects a TCCH having a large correlation value (S222).
The ranging processing unit 110 transmits the IRCH for the selected TCCH via the modulation unit 103, the transmission unit 102, the radio unit 101, and the antenna 100 (S224).

According to the embodiment of the present invention, a TCCH is generated by selecting at least one subcarrier among multicarrier signals formed by a plurality of subcarriers. TCCH can be generated.
Further, by generating TCCHs having different waveform patterns, it is possible to reduce the collision probability with respect to the signal transmitted from the terminal device.
Also, by setting a higher priority for a TCCH with a large number of subcarriers and increasing the number of subcarriers as the number of retransmissions increases, it is easier to receive the TCCH when the number of retransmissions increases.
Further, since the TCCH is easily received when the number of retransmissions increases, an increase in the number of retransmissions can be suppressed.
In addition, since the number of retransmissions is suppressed, channel allocation processing can be shortened.

  Although the best mode for carrying out the present invention has been described above, the present invention is not limited to the configuration of this embodiment, and the scope of application of the present invention defined in the claims. As long as the functions of the configuration of the above-described embodiment can be achieved, various modifications are possible.

  For example, when there is a ranging request from a plurality of terminal devices 2 in the first embodiment of the present invention, a case where a TCH is assigned to each terminal device 2 to perform gradual initial ranging, and a plurality of terminal devices 2 In the above, the case where one TCH is assigned to perform stepwise initial ranging has been described, but these may be combined.

In Embodiments 1 to 3 of the present invention, ranging processor 110 repeats the ranging process of transmitting a ranging response such as IRCH or RCH twice after receiving TCCH.
However, the present invention is not limited to this. For example, the ranging processing unit 110 may repeat the ranging process three or more times.
According to this modification, it is possible to reduce the probability that the TCCH has the same waveform pattern, and to improve the separation accuracy of the plurality of terminal devices 2.

In 1 to 3 of the embodiment of the present invention, TCCH is defined to select at least one of a plurality of subcarriers constituting one subchannel.
That is, TCCH is defined on the premise that a multicarrier signal is used.
However, the present invention is not limited to this. For example, the TCCH may be defined as a single carrier signal.
In this case, the TCCH has a bandwidth corresponding to the bandwidth of at least one subchannel.
Moreover, the base station apparatus 1 receives TCCH as a single carrier signal in a subchannel different from the subchannel to receive TCCH as a multicarrier signal.
In the case of FIG. 5, for example, TCCH as a multicarrier signal is arranged for SC1, and TCCH as a single carrier signal is arranged for SC5.
According to this modification, even if TCCH as a single carrier signal is defined in addition to TCCH as a multicarrier signal, the collision probability between the two can be reduced.

Any combination of Embodiments 1 to 3 of the present invention is also effective.
According to this modification, the effect in the case of arbitrarily combining the first to third embodiments of the present invention can be obtained.

  DESCRIPTION OF SYMBOLS 1 Base station apparatus, 2 Terminal apparatus, 20 Mobile communication system, 100 Antenna, 101 Radio | wireless part, 102 Transmission part, 103 Modulation part, 104 Reception part, 105 Demodulation part, 106 IF part, 107 Control part, 110 Ranging process part 112 allocation unit 200 antenna 202 radio unit 204 transmission / reception unit 206 modulation / demodulation unit 208 IF unit 210 control unit 212 pattern determination unit

Claims (5)

A terminal device that communicates with a base station device,
Transmitter for transmitting a request signal to a base station device by random access using a plurality of subcarriers among multicarrier signals formed by a plurality of subcarriers in order to establish communication with the base station device Including
The terminal device transmits the request signal based on a predetermined density. A communication method in a terminal device that communicates with a base station device,
In order to establish communication with the base station apparatus, transmission is performed so as to transmit a request signal to the base station apparatus by random access using a plurality of subcarriers among multicarrier signals formed by a plurality of subcarriers. Including the step of controlling the part,
The communication method according to claim 1, wherein the request signal is transmitted based on a predetermined density. A program executed by a terminal device that communicates with a base station device,
In order to establish communication with the base station apparatus, a step of transmitting a request signal to the base station apparatus by random access using a plurality of subcarriers among multicarrier signals formed by a plurality of subcarriers. Including
The request signal is transmitted based on a predetermined density. A processor mounted on a terminal device that communicates with a base station device,
In order to establish communication with the base station apparatus, transmission is performed so as to transmit a request signal to the base station apparatus by random access using a plurality of subcarriers among multicarrier signals formed by a plurality of subcarriers. Including the step of controlling the part,
A processor, wherein the request signal is controlled to be transmitted based on a predetermined density. A storage medium for storing a command executed in a terminal device that communicates with a base station device, wherein the command is
In order to establish communication with the base station apparatus, transmission is performed so as to transmit a request signal to the base station apparatus by random access using a plurality of subcarriers among multicarrier signals formed by a plurality of subcarriers. Including instructions to control the part,
A storage medium for storing a command, wherein the request signal is controlled to be transmitted based on a predetermined density.

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