JP2591877B2 - Channel assignment method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a channel allocation method in a multicarrier hopping TDMA system in the field of radio communication such as satellite communication and mobile communication, and in particular, reduces a loss rate of a high-speed call requiring a large number of channels. The present invention relates to a channel allocation scheme to be used.

[0002]

2. Description of the Related Art FIG. 5 shows a multicarrier hopping TDM.
Shows an example of a typical system configuration of a satellite communication system according to A method, which according to the case, the slave station 2 ₁ to 2 _L each channel allocation request based on random call arising from a transmission station number and the receiving station numbers and call When the control station 1 is at the control station 1 via the communication satellite 3 together with the speed type, the control station 1 determines the channel positions to be allocated to the call for the required number of channels, and transmits the channel position to the slave station that has issued the channel allocation request. The channel and the receiving channel are notified to the slave station of the communication destination in advance.
Thus, for example, a burst containing information data can be transmitted and received on the channel between two slave stations. Here, the concept of the channel is referred to as multicarrier hopping TD
As for the MA method, as shown in FIG. 6, for example, the number of channels per carrier is N (N: an integer of 2 or more), and the number of carriers is M (M: an integer of 2 or more). The number of time slots is N and the number of all channels is M ×
N. Data burst 4
If the data rate is the basic rate, any one of the available channels is allocated to a predetermined one. However, as the data rate increases, two or more available channels need to be allocated.

Now, multicarrier hopping TDMA
The following describes the channel allocation method according to the prior art in the system. However, in the following description, for the sake of simplicity, each slave station can transmit and receive only one carrier within one time slot. Therefore, the maximum number of channels that can be transmitted and received at each slave station is the number of channels per carrier (= N). That is, FIG.
829 shows a main configuration of a control station according to a first channel allocation scheme. In this case, the channel management table 7 indicates whether or not each channel is currently idle, and for each non-empty channel, the transmitting station (unique identification) number for each slave station that is currently using it. The receiving station (unique identification) number can be updated at any time, and is managed under the control of the call control management unit 5. Based on a command from the call control management unit 5, the time slot free channel search unit 8
While the channel management table 7 searches the channel management table 7 for an empty channel position in the time slot specified by the call control management unit 5, the used channel number measurement unit 6 determines whether or not the designated transmitting station in the time slot specified by the call control management unit 5 is in use. The total number of transmission channels and the total number of reception channels of the designated reception station are obtained from the channel management table 7 (as described above, the allowable number of transmission / reception channels in one time slot at each slave station is one channel. In practice, it is sufficient to check whether or not there is a transmission channel at the designated transmitting station and whether or not there is a receiving channel at the designated receiving station.)

[0004] More specifically, Fig. 8 shows a channel allocation control flow in the control station shown in Fig. 7. In this case, assuming that a call from the transmitting station 2 _i to the receiving station 2 _j newly occurs, the time slot t ₁ is _first designated from the call control management section 5 to the empty channel search section 8 within the time slot. It is supposed to be. Based on this, the time slot free channel searching unit 8
It has become one idle channel is searched in the time slots t ₁ from the channel management table 7. As a result, when there is an empty channel in the time slot t ₁ , the call control management unit 5 specifies the time slot t ₁ , the transmission station number i, and the reception station number j to the used channel number measurement unit 6. Thereafter, the used channel number measuring unit 6 calculates the total number of transmission channels of the transmitting station 2 _i (presence or absence of transmission channels) and the total number of reception channels of the receiving station 2 _j (presence or absence of reception channels) in the time slot t ₁ from the channel management table 7. It is something that can be done. as a result,
If the transmitting station 2 _i is not currently being used for transmission and the receiving station 2 _j is not currently being used for receiving, one vacant channel in the time slot t ₁ is selected and
The newly generated call (hereinafter, referred to as a new call) is allocated as a used channel. afterwards,
The call control management section 5 completes the process of selecting an empty channel by setting the transmission station number i and the reception station number j at the newly allocated channel position on the channel management table 7. If so, the time slot t
If there is no free channel in ₁ or the transmitting station 2 _i
Is already used for transmission, or the receiving station 2j
If There have been already used in reception, time slot selection idle channel at t within ₁ is impossible, until after idle channel is selected, the target time slot is other time slot t ₂ , T ₃ ,..., T _N , an empty channel is selected by repeatedly performing the same processing. Also, if the new call is a high-speed call and the required number of channels for the new call is k
In the case of (k: an integer of 2 or more) channels, k channels are selected by the same processing and are assigned to the new call. However, if k channels cannot be selected, it is regarded as a call loss. Is to be processed.

Here, the above-mentioned channel allocation method will be described in detail with reference to FIGS. 9A to 9C which show specific examples of the channel management table 7.
After being a matrix structure of M, the element (n, m) in each channel (t _n, f _m) calls using the (A → B)
The transmission station number A and the reception station number B are stored as updatable. However, in FIGS. 9A to 9C,
(O → O) indicates an empty channel, and all channels in each of the elements not shown represent non-empty channels. Now, first, the channel allocation state in FIG. 9 (A), the assuming a case where the number of the required channel has occurred is one channel of the call (1 → 2) to the receiving station 2 ₂ from the transmitting station 2 _1, the call control The time slot t ₁ is designated from the management unit 5 to the free channel within time slot search unit 8, and the free channel within time slot search unit 8 searches the channel management table 7 based on the time slot t ₁ .
An empty channel will be found at the channel (t ₁ , f _M ) position. Based on this, the time slot t ₁ , the transmitting station number 1 and the receiving station number 2 are specified from the call control management section 5 to the number-of-used-channels measuring section 6, and the number-of-used-channels measuring section 6 specifies the time on the channel management table 7 in time slot t _1, but will be examined and the presence or absence of the reception of the transmitting station 2 ₁ receiving station 2 ₂ and the presence or absence of transmission, the result, that the transmission station 2 ₁ is already used for transmission It is something to find. Accordingly, it is intended to determined that idle channel time slots t ₁ the call control management unit 5 is not selectable. Then, subsequently, when the same processing for the time slot t _2, the time slot t ₂ channels _{(t 2, f 2),} (t 2, f M)
While idle channel position is present, already received station 2 ₂
Are used for reception, so that an empty channel (t
₂ , f ₂ ) and (t ₂ , f _M ) are determined to be impossible to select an empty channel. Furthermore, when the same processing for the time slot t _3, the time slot t ₃ Channel (t _3, f ₂₎ idle channel is present at the position, moreover transmitting station 2 ₁ is not been transmitted, the receiving station Since no 2 ₂ has been received, a vacant channel at that channel (t ₃ , f ₂ ) is selected as a channel to be allocated to a new call. Since the required number of channels for the new call (1 → 2) is one,
The selection of the empty channel is now completed and the channel (t ₃ , f
₂ ) is updated to (1 → 2) as shown in FIG. 9 (B).

[0006] In the channel allocation state in FIG. 9 (B), the if further assumed that the required number of channels has occurred a new call (3 → 4) of 4-channel, time slot t _1, t _2, t _N can select empty channels one by one, but cannot select an empty channel from time slot t ₃ , and consequently cannot select four empty channels. Will not be. That is, in the first conventional channel allocation method, every time a time slot is sequentially selected, a vacant channel in the selected time slot is selected. Are frequently selected, and empty channels are biased toward older time slots. Therefore, when a high-speed call requiring a plurality of vacant channels occurs, a vacant channel cannot be selected from a time slot equal to the required number of channels, and the loss rate of the high-speed call is greatly increased. Has become. To solve such a problem, the above-described Japanese Patent Application Laid-Open No. 2-44829 discloses a second channel allocation method, which will be described below.

More specifically, FIG.
FIG. 1 shows a main configuration of a control station according to a second channel allocation scheme shown in Japanese Patent Application Laid-Open Publication No. H11-209,036. As shown in the figure, the only difference from the one shown in FIG. 7 is that the free channel search unit 8 in the time slot is replaced by the free channel search unit 9 in the carrier. An empty channel in the carrier is to be searched. FIG. 11 shows a channel assignment control flow in a control station according to the second channel assignment scheme. In this case, assuming that a call (i → j) from the transmitting station 2 _i to the receiving station 2 _j occurs, the carrier f ₁ is first transmitted from the call control management unit 5 to the in-carrier free channel search unit 9. It is specified. The carrier free channel searching unit 9 searches for the carrier f ₁ on the channel management table 7 to
The presence or absence of an empty channel is searched. As a result, if an empty channel exists at the channel (t _n , f ₁ ) position, the call control management unit 5 sends the time slot t _n , The transmitting station number i and the receiving station number j are specified. The number-of-used-channels measuring unit 6 checks the presence or absence of transmission at the transmitting station 2 _i and the presence or absence of reception at the receiving station 2 _j in the time slot t _n on the channel management table 7. As a result, the transmitting station 2 _i transmits. not without and, also, when the reception station 2 _j is not received, you select the channel (t _n, f ₁₎ free channel from a position, in which the place to assign to the new call. At that time, in the time slot t _n , the transmitting station 2
or _i has already sent, or if the receiving station 2 _j has already received, after having retrieved the other free channels in the carrier f _1, in which similar processing is performed. In carrier f _1, all the result of searching a free channel, if the idle channel is not selected as the allocation channel, since, carrier _{f 2, f 3, ...,} f
Similar processing is performed every time _M is sequentially selected. If the new call is a high-speed call and the required number of channels is k, k channels are selected by the same processing and are assigned to the new call.

[0008] Here, the second channel allocation method is as follows:
If described with reference to specific examples used in the description of the first channel assignment method, the channel allocation state in FIG. 9 (A), the the required number of channels to the receiver station 2 ₂ from the transmitting station 2 ₁ Assuming that the call 1 (1 → 2) occurs, the carrier f ₁ is designated by the call control management unit 5 to the intra-carrier free channel search unit 9, and based on this, the intra-carrier free channel search unit 9 Channel management table 7
By searching for the carrier f ₁ above, an empty channel will be found at the channel (t _N , f ₁ ) position. As a result, the time slot t _N , the transmitting station number 1 and the receiving station number 2 are designated from the call control managing section 5 to the used channel number measuring section 6, and the used channel number measuring section 6 specifies the time on the channel management table 7. in slot t _N, the transmitting station 2 ₁ is not transmitted, also would find that the reception station 2 ₂ has not received. As a result, the call control manager 5 selects the channel (t _N , f ₁ ) position as the assigned channel. Required number of channels is 1
Since it is a channel, the channel assignment is now complete, and the channel (t _N , f ₁ ) position is, as shown in FIG.
It is updated to (1 → 2). Further, in the channel assignment state of FIG. 9C, when a high-speed call (3 → 4) with a required number of channels of four occurs, the four time slots t ₁ , t ₂ , t ₃ , and t _N respectively. , The idle channels are selected one by one and assigned to the high-speed call. That is, in the second channel allocation method, first, a carrier is selected, and then a vacant channel in the carrier is selected. The number of channels is averaged, and it becomes easier to select an empty channel from a number of time slots equal to the number of required channels for a high-speed call, so that the loss rate of a high-speed call can be reduced.

[0009]

SUMMARY OF THE INVENTION As described above, the first
In the channel assignment method of the above, the call blocking rate of a high-speed call increases, whereas in the case of the second channel assignment method,
It is intended to reduce the loss rate of high-speed calls. However, here, for example, the channel assignment state shown in FIG. 12A (the difference between this channel assignment state and the channel assignment state shown in FIG. 9A) is assigned to the channel (t ₃ , f ₁ ) position. Call (2 → 3) is channel (t ₃ ,
f ₂₎ on which is a) assuming only that is assigned to the position, the receiving station from the same transmitting station 2 ₁ the previous example 2
If to ₂ calls (1 → 2) has occurred, first case of the first channel allocation method, channels the above described processes to the new call _{(1 → 2) (t 3} , f 1) Position In addition to the vacant channels being allocated in FIG.
Obviously, it is updated as shown in FIG. Also, in the case of the second channel allocation method, the channel (t ₃ ,
f ₁ ) An empty channel at the position is to be allocated. Therefore, in the channel allocation state shown in FIG.
If 4) occurs, it can be understood that in any of the first and second channel allocation methods according to the prior art, an empty channel cannot be selected from all four time slots, resulting in a call loss. . If a call (1 → 2) occurs,
If any of the available channels at the channel (t _N , f ₁ ) and (t _N , t _M ) positions has been selected, then for a high-speed call with a required number of channels of four, four channels are generated. It is possible to allocate an empty channel.

As described above, in the channel assignment method according to the prior art, as a search direction of an empty channel, each time slot is searched in the carrier direction, or each carrier is searched in the time slot direction.
Since the allocable free channel searched first is selected as the allocated channel, there is a possibility that there is a time slot in which no free channel exists (a time slot that cannot be allocated). Therefore, when a high-speed call requiring a plurality of time slots occurs, there is a problem that the call loss rate increases.

SUMMARY OF THE INVENTION An object of the present invention is to reduce a call loss rate for a high-speed call when performing a multiple traffic operation in which a low-speed call having a required number of channels and a high-speed call having a plurality of required channels coexist. To provide a possible channel allocation scheme.

[0012]

SUMMARY OF THE INVENTION The object of the present invention is basically to provide a control station in which, when a channel assignment request is issued from each slave station together with a transmitting station number, a receiving station number and a call speed type, the control station transmits the channel. By referring to a management table that manages numbers and receiving station numbers, one or more vacant channels are selected according to the call speed type, and when allocating the vacant channels for burst transmission / reception,
2 free channels for the number of channels according to the call speed type
This is achieved by selecting only one free channel from each of the existing time slots and allocating it for burst transmission and reception.

[0013]

In essence, when a new call is made, an empty channel is not present at all by selecting an empty channel while minimizing the selection of an empty channel in a time slot having only one empty channel. The time slot is made as small as possible. Therefore, even when a high-speed call that requires a plurality of channels occurs, the probability that the plurality of channels are selected is improved as compared with the channel allocation scheme according to the related art, and the call blocking rate for the high-speed call can be reduced accordingly. Things.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to FIGS. First, a control station according to the channel allocation method according to the present invention will be described. FIG. 1 shows an example of the configuration of the main part. As shown in the figure, it is configured to include a call control management unit 5, a used channel number measurement unit 6, a channel management table 7, and a time slot free channel search unit 8, which have the functions described above. The configuration is the same as that, and the configuration is such that a free channel number measuring unit 10 is newly added to this configuration. Each time a time slot is designated by the call control manager 5, the number of available channels measuring unit 10 is provided to measure the number of available channels in the designated time slot. Only when there are two or more empty channels in a time slot, as long as the other conditions are satisfied, the system is provided to allow selection of an empty channel from the time slot. When the call control manager 5 instructs the idle channel number measuring unit 10 to measure the number of empty channels in each time slot, the number of empty channels in each time slot is selected prior to the selection of the empty channel. Is to be measured.

The channel allocation control operation in the control station according to the present invention will be described below with reference to FIG. 2 showing the control flow. That is, the transmitting station 2 _i
Assuming a case where a call to the receiving station 2 _j is originated from, first time slot t ₁ in the time slot in the free channel search unit 8 is adapted to be specified from the call control management unit 5. By searching for a time slot in the channel management table 7, the idle channel search unit 8, searches a free channel in the time slot t _1, as a result of the search, if the idle channel is present in the time slot t ₁ Is that the time slot t ₁ , the transmitting station number i, and the receiving station number j are designated from the call control managing section 5 to the used channel number measuring section 6. The number-of-used-channels measuring unit 6 checks the presence or absence of transmission at the transmitting station 2 _i and the presence or absence of reception at the receiving station 2 _j in the time slot t ₁ on the channel management table 7.
As a result, if the transmitting station 2 _i is not used for transmission and the receiving station 2 _j is not used for receiving, the call control manager 5 temporarily determines that the time slot t ₁ can be assigned. Is to be selected. Then
The assignable time slot t ₁ is specified from the call control management unit 5 to the number-of-free-channels measuring unit 10, and based on this, the number-of-free-channels measuring unit 10 uses the free time within the time slot t ₁ in the channel management table 7. After the number of channels is measured, the measurement result is notified to the call control management unit 5. If the measurement result from the call control management part 5 free channel counting unit 10, is not the number of idle channels is 1, i.e., if it is 2 or more, allocatable time slots t ₁ a free channel 1 channel on selected from , New calls. If the measurement result indicates that the number of free channels = 1, the selection of a free channel from the time slot t ₁ is not allowed, and the call control management unit 5 sends a next time to the free channel within time slot search unit 8. by the time slot t ₂ is designated, in which similar processing for timeslot t ₂ is performed. If the free channel even time slot t ₂ is not selected, until a free channel required number is selected by the same process every time the time slots are sequentially updated is repeated,
A required number of available channels are selected.

In general, the required number of channels for a new call is K (K:
If the channel is an integer greater than or equal to 1), the above processing is repeated until k empty channels are selected, but if k empty channels cannot be selected, the number of insufficient empty channels It is sufficient to select a free channel from the tyro slots in which the number of free channels is 1 and allocate it to a new call. If k empty channels cannot be selected even after performing the above processing, it is processed as a call loss for the first time.

By the above channel assignment processing,
A free channel existing in a time slot having one free channel is less likely to be allocated to a new call, and therefore, a time slot having no free channel is less likely to exist. That is, when the above-described idle channel selection processing is adopted, the number of time slots in which an idle channel exists is stochastically increased. It can be reduced.

Here, the channel allocation processing according to the present invention will be described in more detail and specifically as follows. That is, for example, in the channel assignment status in the aforementioned FIG. 12 (A), the by assuming that the required number of channels has occurred is one channel of the call (1 → 2) to the receiving station 2 ₂ from the transmitting station 2 ₁ For example, based on the designated time slot t ₁ from the call control management unit 5, the free channel within time slot search unit 8 searches the channel management table 7,
An empty channel at the channel (t ₁ , f _M ) position will be found. Next, based on the time slot t ₁ specified by the call control manager 5, the transmitting station number 1 and the receiving station number 2, the used channel number measuring section 6 sets the transmitting station in the time slot t ₁ on the channel management table 7. since finding that the 2 ₁ has already been used for transmission, it will be judged that vacant channel selection from the time slot t ₁ the call control management unit 5 is not possible. Then, when the same processing for the time slot t _2, since the time slot t ₂ already received station 2 ₂ is used for reception, the channel _{(t 2, f 2),} (t 2, f M ) It is determined that it is impossible to select an empty channel from the position. Furthermore, when the same processing for the time slot t _3, not in the time slot t ₃ the transmission station 2 _1, the transmission, also because the receiving station 2 ₂ also is not received, the channel (t _3, f time slot t ₃ when empty channel is present which is intended to be temporarily selected as the allocatable time slots ₁₎ position. However, if the number-of-free-channels measuring section 10 measures the number of free channels in the time slot t ₃ on the channel management table 7 based on the designated time slot t ₃ from the call control managing section 5, the measurement result is since the number = 1, which is assumed to be determined that the selected idle channel from the call control management unit 5 in the time slot t ₃ is also possible. Thereafter, similar processing is sequentially performed for each of the time slots up to the time slot t _N−1, but since there are no free channels in these time slots, no free channel can be selected. However, when the time slot t _N is designated by the time slot free channel search unit 8, the call control management unit 5 determines the time slot t _{N based on} a series of subsequent processing results.
Can be assigned, and it is known that the number of vacant channels in the time slot t _N is 2. Therefore, after selecting the time slot t _N , the channel (t
The empty channel at the _N , f ₁ ) position is to be assigned to a new call. Since the required number of channels for a new call in this case is one, the selection of an empty channel is completed at this point, and a new channel is located at the channel (t _N , f ₁ ) position as shown in FIG. The call (1 → 2) is assigned.

In the case of the above-described channel allocation method, the channel allocation process is performed in such a manner that there is no time slot in which there is no free channel. An unused channel (t _N , f ₁ ) that has not been used can be selected. Therefore, in the channel assignment state of FIG. 12C, even if a call (3 → 4) with a required number of four channels occurs, a vacant channel can be easily selected from the four time slots. Thus, it is possible to reduce the loss rate of a high-speed call as compared with the conventional channel allocation method.

In the above description, the allocable free channel in time slot is searched by the free channel in time slot search unit 8. Channel search unit 9
Thus, even if a search for an empty channel is performed, the call loss rate for a high-speed call can be similarly reduced. This is because, when a free channel is included in the carrier, the free channel is selected for the first time on the condition that the number of free channels is two or more in the time slot including the free channel. Incidentally, in the above-described example of channel allocation for a new call (1 → 2), when an empty channel search is performed by the intra-carrier empty channel search unit 9, an empty channel (t _N , f ₁ ).
Are also selected and assigned to the new call.

Now, considering the effect of the channel allocation method according to the present invention, FIGS. 3 and 4 show a traffic volume-loss rate for a high-speed call when a traffic simulation is performed under the conditions shown in FIGS. It shows the characteristics. It should be noted that the total equivalent bandwidth traffic in the figures is the total value of the traffic volume converted to low speed traffic at each of the slave stations. 3 shows a case where the number of slave stations = 32, and FIG. 4 shows a case where the number of slave stations = 4.
FIG. 3 shows that the call loss rate in the channel assignment method according to the present invention is reduced as compared with the conventional method. Also, from FIG. 3, the number of slave stations = 3
In the case of 2, it is also known that the call blocking rate of the second channel allocation scheme is smaller than that of the first channel allocation scheme as a conventional technique. Further, FIG.
Therefore, if the number of slave stations is 4, paying attention to the two channel allocation schemes as the prior art, the call loss rate of the second channel allocation scheme, which was small when the number of slave stations is 32, is: It is larger than the call loss rate according to the first channel assignment method. That is, in the channel assignment system as the prior art, the call loss rate characteristics are reversed between the case where the number of slave stations = 4 and the case where the number of slave stations = 32, whereas according to the channel assignment system according to the present invention, It can be seen that a small call blocking rate can still be realized.

The channel allocation method according to the present invention for selecting a vacant channel by sequentially updating time slots or carriers has been described above. The number of vacant channels in each time slot is determined in advance. Therefore, it is conceivable to select empty channels in order from the time slot in which the most empty channels exist. When the number-of-free-channels measuring unit 10 is instructed by the call control management unit 5 to measure the number of free channels in each of the time slots, the number of free channels in each of the time slots is measured prior to the selection of the free channel. It is only necessary to do so. In this way, when a free channel is selected, the probability of existence of a free channel in each time slot can be averaged, so that even if a high-speed call occurs continuously, a call loss is less likely to occur. Is clear.

[0023]

As described above, according to the first and second aspects of the present invention, the case of performing the multiple traffic operation in which a low-speed call having a required number of channels of one and a high-speed call having a required number of channels coexist is performed. In addition, the call loss rate for high-speed calls can be kept low.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a main configuration of a control station according to the present invention.

FIG. 2 is a diagram showing a channel allocation control flow in the control station.

FIG. 3 shows an example of a call volume-loss rate characteristic for a high-speed call in the channel assignment system according to the present invention, based on traffic simulation, with the number of slave stations being 32, in the channel assignment system according to the prior art. Figure shown in conjunction with

FIG. 4 shows an example of a traffic volume-loss rate characteristic for a high-speed call in the channel assignment system according to the present invention, based on traffic simulation, assuming that the number of slave stations is 4, similarly. Figure shown in conjunction with

FIG. 5 is a diagram illustrating an example of a general system configuration of a satellite communication system based on a multicarrier hopping TDMA scheme;

FIG. 6 shows the multicarrier hopping TDM.
Diagram for explaining method A

FIG. 7 is a diagram showing an example of a main configuration of a control station according to a first channel allocation scheme of the related art.

FIG. 8 is a diagram showing a channel allocation control flow in the control station.

FIGS. 9A to 9C are diagrams showing specific examples of a channel management table.

FIG. 10 is a diagram illustrating an example of a main configuration of a control station according to a second channel allocation scheme of the related art.

FIG. 11 is a diagram showing a channel allocation control flow in the control station.

FIGS. 12A to 12C show other examples of a channel management table.

[Explanation of symbols]

5: Call control management unit, 6: Used channel number measurement unit, 7: Channel management table, 8: Free channel search unit in time slot, 10: Free channel number measurement unit

Claims (2)

(57) [Claims] 1. Prior to each of a plurality of slave stations transmitting and receiving a burst including information data to and from each other, a burst transmission / reception channel is assigned by a control station based on a channel assignment request from each of the slave stations. A channel assignment method in a multi-carrier hopping TDMA system, wherein when a channel assignment request is issued from each of the slave stations together with a transmission station number, a reception station number, and a call speed type, the control station transmits a channel-corresponding transmission station number and a reception station. By referring to the management table for managing the numbers, one or more vacant channels are selected according to the call speed type, and when allocating the vacant channels for burst transmission / reception, the number of channels corresponding to the call speed type is determined. Only one vacant channel from each time slot in which two or more vacant channels exist. A channel allocation method that is selected and allocated for burst transmission / reception. 2. Prior to each of a plurality of slave stations transmitting and receiving a burst including information data to and from each other, a burst transmission / reception channel is assigned by a control station based on a channel assignment request from each of the slave stations. A channel assignment method in a multi-carrier hopping TDMA system, wherein when a channel assignment request is issued from each of the slave stations together with a transmission station number, a reception station number, and a call speed type, the control station transmits the channel-corresponding transmission station number and reception station. By referring to the management table managing the numbers, only one free channel is selected from each of the time slots in which two or more free channels exist by the number of channels corresponding to the call speed type, and the burst is selected. When allocated for transmission and reception, the number of free channels selected depends on the above call rate type. If the number of channels
A channel allocation method in which only one free channel is selected from each time slot in which only one free channel exists for the number of insufficient free channels.