JPH10294704A - Radio communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable one-to-one communication to be conducted among plural equipment without the provision of an exclusive base station that manages time slots related to time division processing. SOLUTION: All radio stations are set to a reception state to monitor a current communication state. In the case that a radio station (caller station) starts communication with other stations, a time slot discrimination section 6 confirms an operating state of each time slot. A time slot decision section 7 assigns its own station to a 1st position of a prescribed number of time slots, when other stations make no communication and a transmission section 3 starts transmission of required data. The caller station using the time slot at the fast position acts as a pseudo-base station, and the first time slot is a timing reference for time division processing, when communication is made among other radio stations. A receiver side station decides a time slot position of its own station based on data relating to the time slot used by the caller station, included in the transmission data and transmits a response signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio communication apparatus, and more particularly, to a radio communication apparatus capable of performing a plurality of sets of one-to-one communication without providing a dedicated base station for managing time slots related to time division. The present invention relates to a time-division wireless communication device.

[0002]

2. Description of the Related Art Conventionally known as multiplex communication technologies are frequency division multiplexing (FDM) and time division multiplexing (TD).
M). The former frequency division multiplexing (FDM) requires a corresponding frequency band to allocate a frequency to each wireless station. Further, the latter time division multiplexing (TDM) enables communication using a common frequency, but requires a dedicated base station for managing time slots related to time division. Therefore, it is necessary to determine which method is to be used by comprehensively considering the characteristics, the purpose of communication, and the like.

[0003]

However, there are cases where it is desired to be able to perform one-to-one communication with a plurality of sets in a small-scale or simple communication system. Therefore, if a communication system which can occupy a narrow frequency band and does not require the installation of a dedicated base station can be realized, it is convenient to construct a communication system as described above. The present invention has been made in view of such a background, and it is an object of the present invention to provide a wireless communication device capable of narrowing an occupied frequency band and enabling multiplex communication without installing a dedicated base station. .

[0004]

SUMMARY OF THE INVENTION According to the present invention, there is provided a radio communication system in which a plurality of other stations emit a radio signal based on a time division format in which one frame period is divided into a predetermined number of time slots. Receiving a communication signal, receiving means for demodulating data, a time slot discriminating section for discriminating a current use state of a time slot based on a received demodulated output by the receiving means, and discriminating by the time slot discriminating section. A time slot deciding section for deciding transmission of a call to a time slot at a required position when the station becomes a calling station; and a memory section for storing data relating to the time slot position decided by the time slot deciding section. Transmitting means for transmitting required data by a radio communication signal based on a predetermined modulation method at the time slot of the determined own station; The time slot determination unit based on the received demodulated output from the receiving means, the time slot determination unit,
An object of the present invention is to provide a wireless communication device including a control unit that controls a memory unit and a transmission unit.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION All radio communication devices (radio stations) are set to a reception state and monitor the current communication status. When a wireless communication device related to a certain wireless station starts communication with another station, the station (calling station) first checks the use state of a time slot related to time division (time slot determination unit).
If it is determined in the above confirmation that the other station is not communicating, the calling station automatically assigns itself to the time slot at the first position in the time division format in which one frame period includes a predetermined number of time slots (for example, six time slots). Assign stations and start transmitting required data. The calling station transmitting using the time slot at the first position is a pseudo base station,
The first time slot serves as a timing reference in time division when communication is started between other wireless stations.

[0006] The communication partner station (called station) called by the signal related to the transmission, based on the data pertaining to the time slot used by the calling station included in the transmission data, according to a predetermined rule. Is determined (for example, the fourth time slot three times after the calling station time slot), and a response is transmitted during this time slot. Thereafter, communication is performed between the two wireless stations. When the other station starts transmission during the communication, the calling station allocates its own station to the time slot at the second position, and communicates with the other station (called station).
Is assigned to the fifth time slot as a time slot for transmitting a response. Further, when the other station starts communication, the calling station allocates to the third time slot,
The called station allocates to the sixth time slot. As a result, when one frame period is composed of six time slots, three sets of one-to-one communication can be performed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a radio communication device according to the present invention will be described with reference to the drawings. FIG. 1 is a main block diagram showing an embodiment of a wireless communication apparatus according to the present invention, FIG. 2 is an operation flowchart for explaining FIG. 1, FIG. 3 is a diagram showing an example of a time-division format, and FIG. FIG.
Before explaining the operation of FIG. 1, the time division format according to the present invention will be described with reference to FIG. FIG. 3A shows an example in which one frame period is divided into six time slots No1 to No6, and the period of each time slot is set to 10 ms. Therefore, one frame period is 60 ms.
Becomes The number of time slots in one frame period and the period of each time slot are arbitrary.

In the communication according to the present invention, a plurality of sets of one-to-one communication are performed based on a predetermined time division format. In the case of FIG. 3A, three sets of independent communication are possible. Become. The communication itself is performed by a required digital modulation method. For example, PSK (phase shift keying) or FSK (frequency shift keying) is used. In addition, a spread spectrum modulation method may be used. PS
In the case of K or FSK, all stations can use the same radio frequency because the communication method in the present invention is time division communication. When the spread spectrum modulation method is used, the same spread code can be used. This allows all wireless stations to monitor the communication status of other stations. Also, the station (calling station) which starts transmission uses (assigns) the No. 1 time slot at the first position with the highest priority, and uses the No. 2 time slot at the next position when this is used. If this is also used, the No. 3 time slot is used.
In other words, the No. 1 time slot is the highest in the use priority order, and is used in the order of the No. 2 and No. 3 time slots.

FIG. 1 will be described on the premise of the above. In addition,
The ST numbers in parentheses in the following description indicate each step in FIG. Each wireless station including the wireless communication device having the configuration shown in FIG. 1 (hereinafter abbreviated as “communication device”) sets the device to a reception state (ST1). Therefore, under the control of the control unit 10, the switching circuit SW1 for switching between transmission and reception is set on the receiving side (a side). As a result, the signal from the antenna 1 is input to the receiving unit 2 via the switching circuit SW1, where processing such as high-frequency amplification and frequency conversion (RF / IF unit 2a) and RF / IF unit
From the signal (modulated signal) from 2a, the data Do is demodulated (demodulation unit 2b). Each of the communication devices in the receiving state as described above identifies whether or not the demodulated output from each of the receiving units 2 includes the own station code indicating the calling of the own station (ST2). This identification is performed by the own station code identification unit 4. The case where the own station code is included in the above identification will be described later, and here, it is assumed that the own station code is not included (ST2-N).

[0010] Here, when a communication device (referred to as communication device A) related to a certain wireless station starts transmission (calling) to a communication device (referred to as communication device a) related to another wireless station, the transmission is started. (Transmission command signal S1) is determined by the transmission command determination unit 5 via the control unit 10 (ST3-Y). When this determination is made, the time slot determining unit 6 determines the current use state of the time slot based on the demodulated output from the receiving unit 2 under the control of the control unit 10 (ST
4). The demodulated output from the receiving unit 2 is not particularly provided as a demodulated output when no communication device is performing communication (this is referred to as no signal), and when communication is performed between other communication devices. The corresponding data is demodulated. Although a format example of the signal will be described later, the data includes data relating to the position of the time slot used in addition to the original information data.

From the above, if the demodulated output is a no signal, the time slot discriminating section 6 can discriminate that no time slot is used, and can discriminate the time slot even if it is used. Here, it is assumed that it is determined that no time slot is used. Based on this determination, the time slot determination unit 7 determines the time slot to be used for transmission (calling) as the No. 1 time slot under the control of the control unit 10 (ST1).
5). Data indicating the determined No1 time slot is included in the transmission data. In addition, data relating to the position of the time slot determined by the time slot determination unit 7 is stored in the memory unit 8.

Thereafter, using the determined No. 1 time slot, the communication device A serving as the calling station starts transmission (calling) (ST6) and communicates with the partner station (ST7). At the time of the transmission, the control unit 10 switches the switching circuit SW1 to the transmission side (b side). The transmitting unit 3 is provided with the illustrated functional blocks, and time-division transmission is performed by the control unit 10 controlling the modulation unit 3a. In addition to input data Di and the like, required data Ds such as data indicating the determined No1 time slot are provided in the modulation section 3a.
, And performs modulation processing at the time slot No. 1. For this time division, the modulator 3a has a function of temporarily pooling data. The output of the modulation unit 3a includes an output unit 3b for performing frequency conversion and setting of transmission output, and a switching circuit SW1.
, And transmitted from the antenna 1.

Next, a description will be given of an operation until a communication device (hereinafter referred to as a communication device a) of a receiving station in response to a call from the communication device A initiates communication by replacing FIG. 1 with the communication device a. When the calling station calls the wireless station of the communication partner, the code (own station code) of the station (calling station) is included in the transmission data. Whether the own code is included in the demodulated output of the receiving unit 2 is monitored by the own code identification unit 4. Here, when the own station code is included (ST2-
Y) Under the control of the control unit 10, the time slot determination unit 7
To determine the time slot to use for response transmission (ST
8). This time slot is the time slot (No.) of the calling station (communication device A) included in the demodulated output of the receiver 2.
It is determined according to a predetermined rule based on the data indicating 1). As this rule, for example, it is assigned to a time slot that is a predetermined number after the time slot of the calling station. Here, when the "predetermined number" is set to "3", the time slot of the called station is determined to be No. 4 time slot. The data relating to the determined time slot position is stored in the memory unit 8. The called station uses the determined No. 4 time slot to start transmitting a response from the transmitting unit 3 (ST4).
9) Thereafter, communication with the calling station is performed (ST10). As a result, one-to-one communication using the No. 1 time slot and the No. 4 time slot is performed between the communication device A and the communication device a. This communication state is shown in FIG.

When ending the communication, when terminating from the calling station, data relating to the communication end flag is transmitted to the receiving station and terminating (ST11). When terminating from the receiving station, receiving is performed. The calling station transmits a communication end request flag to the calling station, and the calling station that has received this transmits data related to the communication end flag to end the processing (ST12). Whether or not the communication is terminated is determined by the communication termination determining unit 9, and when the communication is terminated (ST11).
-Y or ST12-Y), and again set to the receiving state under the control of the control unit 10 (ST1).

Next, while communication is being performed between the communication device A and the communication device a, a communication device (hereinafter referred to as a communication device B and a communication device b) relating to another wireless station performs communication. The case of performing is described with reference to FIG. Here, the calling station is called a communication device B, and the called station is called a communication device b. In this case, the time slot determination unit 6 of the communication device B serving as the calling station:
It is determined that the No1 time slot and the No4 time slot are used. Based on this determination, the time slot used for calling is determined to be the No. 2 time slot at the second position of the use priority (time slot determination unit 7). The data relating to the determined time slot position is stored in the memory unit 8. On the other hand, the communication device b serving as the receiving station determines the No. 5 time slot three times after the No. 2 time slot in accordance with the above-described rule based on the transmission data.
Five time slots are stored in the memory unit 8. As a result, one-to-one communication using the No. 2 time slot and the No. 5 time slot is performed between the communication device B and the communication device b. This communication state is shown in FIG.

Next, while communication is being performed between the communication device A and the communication device a and between the communication device B and the communication device b, a communication device (another radio station) related to another wireless station. The case where the communication device C and the communication device c perform communication will be described with reference to FIG. Here, the calling station is called a communication device C, and the called station is called a communication device c. In this case, the time slot determination unit 6 of the communication device C serving as the calling station:
It is determined that the No1 time slot and the No4 time slot and the No2 time slot and the No5 time slot are used. Based on this determination, the time slot used for calling is determined to be the No. 3 time slot at the third position in the use priority order (time slot determination unit 7). The data relating to the determined time slot position is stored in the memory unit 8.

On the other hand, the communication device c serving as the receiving station also determines the No. 6 time slot three times after the No. 3 time slot based on the transmission data, and stores the No. 6 time slot in the memory unit 8. As a result, one-to-one communication using the No. 3 time slot and the No. 6 time slot is performed between the communication device C and the communication device c. This communication state is shown in FIG. As described above, one frame starts from No1
When the time slot is configured with six No. 6 time slots [FIG.
(A)] Three sets of one-to-one communication are possible. In the above description, the time slot used by the receiving station is determined by the receiving station in accordance with a predetermined rule based on the data indicating the time slot of the calling station included in the demodulated output of the receiving unit 2. did.

In this method, the calling station side determines the time slot of the own station and also determines the time slot used by the called station for response transmission (time slot determining section 7). The data related to the time slot may be included in the transmission signal. The receiving station determines its own time slot based on the demodulated output of the receiving section 2. Further, when the calling station determines the time slot of the receiving station, it is preferable that rules for the determination be determined in advance.
For example, a time slot after a predetermined number of time slots used by the own station is determined. As a specific example, if the own station has the No. 1 time slot, the called station is three times later.
No. 4 time slot is determined.

Next, an example of a signal format in the above-described communication will be described. FIGS. 4A and 4B show examples of the signal format. In FIG. 3A, P is a preamble, SW is a synchronization word, CAC is a control signal, TC
H is information data (video, audio, etc.), and G is a guard bit. In the above, the preamble is for the stabilization period of the RF signal, and during transmission, the signal of the antenna output is stabilized during this period, and during reception, P is set within this period.
LL is locked, and the clock for data reproduction is stabilized. The synchronization word is a signal for synchronizing with a TDM (time division) frame. When the receiving side can detect the synchronization word, it can be confirmed that the signal is a regular signal and synchronizes with a time slot. be able to. The guard bit is for preventing overlapping with the next slot signal, and prevents the next slot from being affected by propagation delay or the like. Also, FIG. 2B shows the CAC of FIG.
, CS is a calling flag, RS is a response flag, TS is data relating to a time slot position, R
E is a communication end request flag, E is a communication end flag, MID
Is a local station calling code, and UID is a partner station calling code.

[0020]

As described above, according to the present invention, time-division multiplex communication can be performed without providing a dedicated base station for time slot management, which has been required conventionally. Thereby, the communication system can be simplified and a plurality of one-to-one communication can coexist. Also, because of the time-division communication, the same radio frequency may be used, and the device of each radio station can be shared. As described above, the present invention can be said to be effective when it is desired to perform one-to-one communication with a plurality of sets in a small-scale or simple communication system.

[Brief description of the drawings]

FIG. 1 is a main block diagram showing an embodiment of a wireless communication apparatus according to the present invention.

FIG. 2 is an operation flowchart for explaining FIG. 1;

FIG. 3A is a diagram showing an example of a time division format;
(B) through (d) are diagrams illustrating examples of communication states based on (a).

FIGS. 4A and 4B are diagrams illustrating signal format examples.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Antenna SW1 Switching circuit 2 Receiving part 2a RF / IF part 2b Demodulation part Do demodulation data 3 Transmission part 3a Modulation part 3b Output part Di input data 4 Self-station code discrimination part 5 Transmission command discrimination part 6 Time slot discrimination part 7 Time slot Decision unit 8 Memory unit 9 Communication end determination unit 10 Control unit

Claims (7)

[Claims] 1. A wireless communication signal according to a predetermined modulation method, which is issued from a plurality of other stations, based on a time division format formed by dividing one frame period into a predetermined number of time slots, and receives data. Receiving means for demodulating, a time slot discriminating section for discriminating the current use state of the time slot based on the demodulated output received by the receiving means, and the own station becomes the calling station based on the discrimination by the time slot discriminating section. A time slot determining unit for determining the transmission of a call to a time slot at a required position, a memory unit for storing data relating to the position of the time slot determined by the time slot determining unit, and the determined own station. Transmitting means for transmitting required data by a radio communication signal based on a predetermined modulation method during a time slot of A wireless communication apparatus comprising: a control unit that controls the time slot determination unit, the time slot determination unit, the memory unit, and the transmission unit based on power. 2. The method according to claim 1, wherein the determination of the time slot used by the own station for transmitting a call is performed by the time slot determination unit, and when no time slot of the one frame period is used, the one frame period is determined. The first time slot or, when the first time slot or a plurality of time slots after the first time slot are used, determine the next vacant time slot. The wireless communication device according to claim 1. 3. A transmission command discriminating unit for discriminating whether a command signal to transmit from a local station has been input is provided on the control unit, and when the transmission command discriminating unit discriminates a transmission command, 3. The wireless communication apparatus according to claim 1, wherein the determination by the time slot determination unit and the determination by the time slot determination unit are performed. 4. A self-station code identification unit for identifying whether there is a self-station code for calling a self-station based on a reception demodulation output from said reception means, provided in said control unit, When the own station code is identified, the time slot determining unit determines a time slot to be used for response transmission based on the received demodulated output, and performs a response transmission by the transmitting unit at the time slot according to the determination. The wireless communication device according to claim 1, wherein: 5. The method according to claim 1, wherein a time slot used for the response transmission is determined to be a time slot after a predetermined number from the position of the time slot used by the calling station calling the own station. The wireless communication device according to claim 4. 6. The calling station determines a time slot used by the called station for transmitting a response in the time slot determining unit,
The wireless communication device according to claim 1, wherein the data relating to the determination is transmitted by the wireless communication signal. 7. A communication end determining unit for determining whether communication with a partner station has been completed is provided under the control unit, and when the communication end determining unit determines that communication has ended, a receiving state is set. The wireless communication device according to claim 1, wherein: