KR20000010975A - Channel hopping in a radio communications system - Google Patents

Abstract

PURPOSE: A channel hopping device for mobile stations and a base station is provided to solve the problem of how channels shall be allocated to the different connections between a base station and mobile stations that are located within the area covered by the base station. CONSTITUTION: A channel allocation(211) within the base station (BS1) generates channel hopping sequences that are transmitted via a control channel (SACCH) to hopping sequence lists(204-206) in the mobile stations (MS1-MS3). The hopping sequences are also transmitted to corresponding hopping sequence lists(201-203) in the base station (BS1). A channel hopping sequence is divided into a number of sequence intervals corresponding to the time between two adjacent channel hops within a channel hopping sequence. In the channel allocation(211) the attenuation of the connections (F1-F3) and the interference of the channels are continuously being observed within each sequence interval. The channel allocation(211) generates channel hopping sequences according to the principle that a connection that has poor connection quality will be allocated a channel hopping sequence with channels of high channel quality and connections with successively better connection quality are allocated channel hopping sequence having successively poorer channels.

Description

Channel Hopping in Wireless Communication Systems

As used herein, the term 'channel hopping' refers to a communication between different information transmission channels, such as, for example, hopping between frequencies, hopping between time slots, and hopping between frequencies and timeslots in a wireless communication system. It is used in the comprehensive sense of hopping.

As will be appreciated by those skilled in the art, frequency hopping may be used to improve the performance of a wireless communication system or as a countermeasure for wireless eavesdropping. Frequency hopping is performed in a predetermined order in the system without considering connection quality. Frequency hopping in wireless communication systems is therefore not smooth.

Between the transmitting device and the receiving device in the wireless communication system, a wireless connection for establishing wireless communication is established. The connection is bidirectional, i.e. a downlink that forms a connection from the base station to the mobile station in the system, and the opposite connection from the mobile station to the base station. It includes an uplink (uplink) to form a. The transmission and reception of radio traffic over these different connection paths is a given frequency in a frequency division multiple access (FDMA) system, or time division multiple access (TDMA). Is affected by the channel, which can be defined by a given inter-frequency and timeslot combination in the system. The channel may be defined by a code in a Code Division Multiple Access (CDMA) system. In general, the available channels in a wireless communication system cause severe disturbances by other radio traffic, such as radio signals of the same frequency over another connection path, so that each channel in the system has a certain interference level. . In other words, if each connection uses only one channel, the connections may have different interference levels. The degree of interference encountered in some connections may be so bad that the call quality is out of acceptable range. The call quality difference between these connections can be leveled by jumping between channels having different interference levels. This makes it possible to use a wide variety of inter-connection channels, and with the help of interleaving and error correction coding, more channels can achieve an acceptable range of call quality throughout the system.

Each connection may be assigned a number of channels, the system being responsible for controlling these connections during communication, such as generating inter-channel hopping in accordance with a given hopping rule. The rule may be, for example, a pseudorandom series. In that case, the connections would appear to hop randomly between all available channels, as described in European patent application EP93905701-4. However, since these channels are not always assigned to each connection in the optimal manner in which the mock random series is used, this type of channel hopping causes unnecessary high interference levels.

Another form of channel hopping is periodic channel hopping. In the case of periodic channel hopping, hopping between multiple channels proceeds according to a periodically repeated channel hopping sequence.

It is well known that channel hopping can be applied to GSM systems. The GSM system is a TDMA system that divides each frequency into multiple timeslots forming one TDMA frame. In the GSM system, one TDMA frame consists of eight timeslots. When establishing a connection between a base station and a mobile station under a GSM system, the connection is assigned to one of these timeslots in each TDMA frame. Subsequently, channel hopping is achieved by hopping the connection between channels having the same timeslot (in fact, the connection only hops between different frequencies). According to the GSM details, a particular frequency occurs only once in one channel hopping sequence, and the frequencies in the channel hopping sequence appear in increasing order of their value. In contrast, the duration of these channel hopping sequences may vary from base station to base station.

A wireless communication system will typically include a number of available channels to form a connection between a given base station and a mobile station. It is important not to use the same channel simultaneously for two or more connections between the base station and mobile stations. If two base station side transmitters transmit their respective different signals over the same channel, it is certain that at least one receiver will be severely disturbed by the transmission to the other receiver. If this cannot happen, i.e., only one of the base station side connections can be transmitted over one channel at each point, then the base station is said to have orthogonality.

If one connection in a wireless communication system is too weak to obtain acceptable call quality, this may be due to an extremely low ratio between signal strength and interference. The signal strength means the strength of the desired signal received. By interference amount is meant the sum of the signal strengths of all the unwanted signals received on the channel currently in use. These unwanted signals are mainly received from other connections using the same channel in adjacent cells in the wireless communication system. The unwanted signals are also received from connections using adjacent frequencies or timeslots within the same cell.

The signal strength of the desired signals received depends on the transmission power and the degree to which the signal is attenuated on the way from the transmitter to the receiver. Attenuation is determined by external factors such as distance, direction, and topography between the transmitter and receiver. Other terms related to this attenuation include path gain and path loss, as will be appreciated by those skilled in the art.

Channel hopping in a wireless communication system is described in international patent application WO 96/02979. Channel hopping occurs between multiple channels assigned to each connection. Signal attenuation parameters, eg path gain, are measured for each connection, and these connections are then organized according to the attenuation parameter. The method as described includes measuring an average value of channel quality parameters such as the amount of interference for each channel. The channels are then organized by channel quality parameter as measured above. Only channels that exhibit the best channel quality are used for the connection.

In assigning a channel hopping sequence for connections, attention is paid to each connection quality and the channel quality of the channels in each channel hopping sequence. For low quality connections, the channels used assign a channel hopping sequence with high quality, and for high quality connections, the channels used assign a channel hopping sequence with low quality (lower). The division of these channel hopping sequences for the connections ensures that the orthogonality is established in each base station. The channel hopping sequence may include a different number of channels per base station. The number of channels used in one channel hopping sequence is fixed within base station range.

Swedish patent application SE94022492-4 discloses a channel hopping method and apparatus in a wireless communication system. The average amount of interference per channel in the wireless communication system is determined, i.e. measured, for each connection. The obtained values are stored in the related interference amount list for each connection. Corresponding values in the interference list are then weighted, and the resulting weighted lists are analyzed. Then, based on these analysis results, a hopping sequence list for each connection is created. A channel with a high weight for a given connection will appear more frequently than a channel with a low weight within its hopping sequence.

The aforementioned method provides an average amount of interference. However, the amount of interference may change over time, and as a result, the amount of channel interference may vary at different time intervals within one channel hopping sequence. Therefore, in a channel hopping sequence in which one channel can be used, it is desirable to obtain interference values within the different time interval range.

U.S. Patent Application U.S. 4,998,290 discloses a wireless communication system using frequency hopping. The system includes a central control station that assigns a communication frequency to a number of participating local wireless stations. The control station forms an interference matrix that will reflect the capacity requirements for each wireless station and the amount of interference for all connections.

One drawback of this method is the need to install a central control station in the system, which makes the system more complicated.

German patent application DE 4403483A discloses a method for reconfiguring a frequency jump group for FDM / TDM radio transmission. A number of timed frequency hopping tables are stored in the base station controller, i.e., the BSC. Use one table (TAB) at a time. If the quality of any connection using one of the frequency hopping sequences in the table is poor, replace the table TAB with a new table TAB1. Switching from the current table to the new table is done in stages. In one embodiment for illustration, the frequency hopping sequences are changed two timeslots at a time. The switching, i.e., the change, is made only if no information is transmitted on these timeslots.

One drawback of this method is that the frequency hopping table is predefined. If the state of the interference is still not known, the best channels for the amount of interference are not available in an optimal form. Another drawback is that the attenuation of each connection is not taken into account in assigning a hopping sequence to the connections.

International patent application WO 91/13502 discloses a carrier-divided frequency hopping method. All available frequencies in a wireless communication system that are available for frequency hopping are found in a frequency pool from which channel hopping sequences are determined. In frequency hopping, each base station is allowed for these frequencies from the frequency pool. In assigning timeslots to mobile stations that wish to establish a connection, the distance from the base station to the mobile stations is taken into account. Neighboring mobile stations are given the most central timeslot in the TDMA frame, whereas for distant mobile stations, the timeslots located at the beginning and end of the TDMA frame are given. This is to avoid duplication between timeslots.

International patent application WO 93/17507 discloses a communication method under a TDMA cellular mobile wireless communication system using frequency hopping. One mobile station in a cell selects a radio channel and timeslots, regardless of a neighboring cell in the cell. Since the hopping sequences in the cell are selected, no co-channel interference occurs. Redundant channel interference may occur between cells, but its magnitude is considered small. In the case of the mobile stations, the mobile station in close proximity to the base station is controlled at that output to transmit at a lower output compared to the remote station.

One drawback of the methods described in the latter two patent applications is that the interference situation is not taken into account in the preparation of the hopping sequence. Another drawback is that in assigning a hopping sequence to connections, no attenuation on that connection is taken into account.

The present invention relates to the field of wireless communications, and more particularly, to a method of channel hopping between different channels in a wireless communication system. The invention also relates to an apparatus in a wireless communication system for applying the method. The proposed method is applicable to frequency division and time division systems, such as FDMA and TDMA systems, and the same for CDMA systems.

1A is a schematic diagram illustrating a part of a wireless communication system;

1B is a schematic diagram showing a base station and three mobile stations located in a cell under the wireless communication system, and the channel hopping principle of the present invention;

2 is a schematic diagram showing a base station and three mobile stations located in a cell under a wireless communication system, and also channel hopping of the present invention;

3A is a schematic diagram showing a first embodiment of the present invention;

3B is a view showing a first embodiment of channel quality generating means according to the present invention;

3c is a view showing a second embodiment of the channel quality generating means according to the present invention;

4 is a view showing a second embodiment of the present invention;

5 is a view showing a third embodiment of the present invention;

6 is a view showing a fourth embodiment of the present invention;

7 is a schematic flowchart illustrating the inventive channel hopping method.

The present invention addresses the problem of how to allocate each channel for different connections between the base station and the mobile stations in the area covered by the base station. The base station forms part of a wireless communication system using channel hopping. Here, one problem in assigning a channel to each connection is encountered, and these connections do not interfere with each other more than necessary, and preferably only minimal interference is achieved to ensure a good connection quality. The way is not to take. This problem also relates to a method that can ensure orthogonality in the base station.

Another problem is how to keep track of the quality of channel hopping channels under the wireless communication system at different time intervals within the channel hopping sequence to maintain reliable quality values.

Accordingly, one object of the present invention is to optimize the use of the available base station channels with the aid of a channel hopping method in terms of connection quality between the base station and the mobile stations in the area covered by the base station. There is.

Another object of the present invention is to investigate channel quality under a wireless communication system at different time intervals within a channel hopping sequence.

Another object of the present invention is to ensure orthogonality in the base station, i.e. base station orthogonality, in connection with the optimization of channel use mentioned above, so that only one base station connection is available in that base station at a time. To use.

The problems are solved by the inventive method and wireless communication system. The method may include examining the connection quality and the channel quality of the corresponding system, where signal attenuation parameters and channel quality parameters are generated.

The signal attenuation parameter indicates the extent to which the connection is affected by attenuation. A low signal attenuation parameter value means that the connection is attenuated to a lesser extent, while a larger signal attenuation parameter value means a larger degree of attenuation.

The channel quality parameter indicates the extent to which the channel or frequency is disturbed due to interference. A low channel quality parameter value means that the channel or frequency is subject to a small amount of interference, while a high channel quality parameter value means a lot of interference.

In the method of the present invention, it is assumed that the number of channels in the channel hopping sequence is constant under the wireless communication system, which is represented by the meaning that all connections in the system use the same hopping sequence duration.

The hopping duration, and the channel hopping sequence related thereto, are divided into several sequence intervals in generating the channel quality parameters. The sequence interval may also be divided into one or more generation intervals in which the channel quality parameter is generated.

According to the method, one channel quality parameter is generated for each frequency and every generation interval.

Channel hopping sequences may be generated according to preset channel quality parameters. Corresponding channel hopping sequences are then assigned to each connection according to the connection quality parameters and channel quality parameters.

More specifically, the inventive method may include investigating connections under the system in terms of connection quality. The connection quality is related to the degree to which the attenuation affects the connection. Signal attenuation parameters such as path gain are determined for each connection. These connections are then arranged according to the predetermined signal attenuation parameter.

The inventive method may also include investigating the quality of channels or frequencies (if applicable) in the system. Channel quality may indicate the extent to which a channel or frequency is disturbed due to interference. Channel quality parameters, such as the amount of interference, are determined for each frequency and for each generation interval. The channel quality parameter is secured for each frequency and for each channel according to the duration of the generation interval and the type of the wireless communication system. If the generation interval is a timeslot under a TDMA system, the channel quality parameter will be determined for each channel. These channels, or frequencies, are then arranged according to the preset channel quality parameters. The channels / frequency are arranged on the channel list for each sequence interval according to the determined channel quality parameters.

The channel quality parameter may also be obtained by, for example, measuring a C / I value or bit error rate (BER) and then calculating the interference amount value using these C / I values or bit error rates as input values.

Subsequently, channel hopping sequences are generated. Each channel hopping sequence uses a channel taken from each channel list for each sequence interval. Only the highest channels are used in the channel quality parameter.

Hopping sequences are then assigned to the connections according to the principle that a connection with poor connection quality is assigned a channel hopping sequence of channels of high channel quality. Connections with progressively better connection quality are also assigned a channel hopping sequence with progressively poorer channels. This means that the less the connection is attenuated in terms of attenuation or other connection quality measurements, the better the channel assigned to that connection is in terms of interference or other channel quality measurements. By allowing only one given channel to appear once within each sequence interval range, orthogonality in the base station is ensured.

It should be noted that the term high channel quality or low channel quality refers to the quality of the channels actually used in the channel hopping sequences. Channels not used in the channel hopping sequence have poorer channel quality than the worst channel used in the channel hopping sequence.

The connections then hop between the channels assigned to them. One channel in the channel hopping sequence is used for each section interval. After using the last channel in the channel hopping sequence, the first channel in the channel hopping sequence is used again, and so on.

The inventive method may be used continuously or intermittently, where channel assignments for older connections are updatable. Since the method is repeated, any newly established connections may be assigned channels that may hop between them. The invention also includes an apparatus for carrying out the method.

An advantage of the method is that it can secure both the quickness in channel assignment and the orthogonality in the base station at the same time.

Another advantage is that the quality of the channels included in the channel hopping sequence is determined at different time intervals within the available channel hopping sequence. This means accurate channel quality investigation. This also allows the advantage of channel hopping, i.e., the amount of interference splitting for each connection, to the advantage of wireless communication systems that do not use channel hopping. In such a system, the interference situation can be investigated channel by channel.

As another advantage, the method of the present invention can improve channel utilization by assigning a channel having a low interference amount for a high attenuation connection and a channel having a high interference amount for a low attenuation connection. do. These advantages can result in improved call quality for more connections and increased capacity and lower overall interference levels in the wireless communication system.

Hereinafter, the present invention will be described in detail through preferred embodiments with reference to the accompanying drawings.

1A illustrates a portion of a wireless communication system. As shown, the system is a cellular mobile radio network (PLMN), which includes base stations BS1 -BS8. Each base station has a range of possible wireless communications with mobile wireless stations or mobile stations MS1-MS6 located within its jurisdiction. Cells C1-C8 represent the geographical range covered by the base stations BS1-BS8. The base stations are connected to the remaining nodes on the corresponding mobile wireless network, for example, a base station control center (BSC), a mobile switching center (MSC), and a gateway mobile switching center (GMSC) according to the known technology. have. Since these points are not very important with respect to the present invention, they are not described in detail in the specification as well as in the drawings.

1B schematically illustrates the principle of channel hopping according to the present invention. Base stations in the wireless communication system include hopping sequence lists. These lists contain information about the channels that the base station will use to communicate with mobile stations in the jurisdiction of the base station. That is, when a base station handles multiple connections with individual mobile stations, the base station will maintain a list of hopping sequences for each connection.

In other words, the base station BS1 in the cell C1 has a hopping sequence list 101 for connection with the mobile station MS1.

The corresponding hopping sequence list for connection with mobile stations MS2 and MS3 is not shown. The hopping sequence list 101 in the base station BS1 includes three transport channels ch1-ch3 denoted by Tx and three receive channels ch4-ch6 denoted by Rx. The time taken to pass through the channel hopping sequence is divided into several sequence intervals (T _i ). That is, the base station-side transmitter transmits the channel ch2 over the whole or part of the second sequence interval T ₂ through the channel ch1 over the whole or part of the first sequence interval T ₁ . ) And over all or part of the third sequence interval T ₃ through channel ch3. The index i representing the sequence interval _Ti number is the sequence index. These three channels are said to form one channel hopping sequence for transmission from the base station BS1 to the mobile station MS1. The transmission from the base station to a given mobile station, or vice versa, may be offset in time within the corresponding sequence interval range. After using the last channel in one channel hopping sequence, the first channel in that channel hopping sequence is used again, and then proceeds in that fashion.

The hopping sequence ch1-ch3 may then be created with a new channel assignment on the hopping sequence list 101 while a wireless connection with the mobile station MS1 is established, or as described below. Until repeated periodically. The receiving device in the base station BS1 receives the sequence intervals T ₁ -T ₃ through the channels ch4-ch6, and thereafter, in the same manner as described above with respect to the transmitting device. The channel hopping sequence is repeated. The number of channels used in the channel hopping sequence, in other words, the sequence duration L, is a system parameter that can be arbitrarily selected. However, the sequence duration L must be the same for all base stations in the system for the following obvious reasons.

The mobile station MS1 includes a hopping sequence list 102. Although the channel hopping sequence used for transmission in the base station is of course used for reception in the mobile station, and the channel hopping sequence used for reception in the base station is used for transmission in the mobile station, The hopping sequences in the hopping sequence lists 101 and 102 are the same. That is, when associated with the sequence interval T ₁ -T ₃ on the mobile station MS1 side, the channels ch1-ch3 form a corresponding channel hopping sequence upon reception, and the channels ch4- ch6) forms a channel hopping sequence in transmission.

The channels stored in the hopping sequence list and used by the base station and the mobile station are selected in accordance with the inventive method described below. However, some key principles may have already been explained. The channel hopping sequence is preferably generated at the base station, like the channel hopping sequence for transmission from the base station. As is well known to those skilled in the art, the use of dual spacing, which is the frequency interval between the uplink and the downlink, ensures a channel hopping sequence for reception in the base station. The resulting hopping sequence list in the base station is sent from the base station to the mobile station via the control channel and used as the hopping sequence list, in the manner mentioned above. The base station side hopping sequence list 101 transmission towards the hopping sequence list 102 in mobile station MS1 is shown in dotted lines on FIG. 1B.

By generating a channel hopping sequence at the mobile station and then using the double interval, another channel hopping sequence may be secured, thus obtaining a hopping sequence list for the base station. As mentioned earlier, this list is sent to the base station via the control channel.

Another alternative method is to generate the respective channel hopping sequences for transmission and reception on a per-connection basis in either the base station or the mobile station without using the double spacing. This possibility can also be used for systems that do not use double spacing. This is described in the embodiment with reference to FIG. 6.

FIG. 2 is a schematic diagram showing part of the three mobile stations MS1-MS3 and the base station BS1 in the cell 1 on FIG. 1A. The base station provides means such as circuitry for storing hopping sequence lists 201-203 for each of the three connections between the mobile stations and the subscribers a1-a3, which may be stator or mobile subscribers. Include. The mobile stations include circuitry for their respective hopping sequence lists 204-206, as described above, these lists are counterparts of the hopping sequence lists in the base stations. In the embodiment, the hopping sequence lists 201-206 may include three transport channels and three receive channels.

The base station includes a receiver 207 for transmitting / receiving a radio signal to / from the mobile station via the assigned channels. The receiving unit of the apparatus 207 may also be used to measure the channel quality through a method such as measuring the amount of interference for each channel used in the system. As generally seen, the amount of interference is channel dependent and time dependent so that it can be expressed in the form of I (channel, t). Instead of using the receiver unit of the apparatus 207 for channel quality measurement, a separate broadband receiver may be mounted in the base station. In the following example, however, it is assumed that the receiver section of the water transmission apparatus 207 is used to measure channel quality.

Each mobile station MS1-MS3 includes its own number and transmission apparatus 208-210 for radio signals to / from the base station. The amount of interference I (channel, t) is also received by the mobile station side receiver. The channel assignment means 211 in the base station BS1 allocates respective channels forming the channel hopping sequence in the hopping sequence list, as described below. These hopping sequences are then transferred from channel assignment means 211 to the base station side hopping sequence list 201-203 and also to the mobile station side hopping sequence list 204-206, where As mentioned, a control channel such as the SACCH (Slow Associated Control Channel) may be used for transmission to the mobile station. Channel hopping sequence transfers to the hopping sequence list 204-206 are shown by dashed lines in the figures for clarity. However, the transfer is made in a known manner under the support of the water transport apparatus 207-210 and the control of the central processing unit (CPU) (Fig. 3). Base station and mobile station communicate with each other directly, via the channel hopping sequence is known to happen channel transmission and reception within each sequence interval (T _i) range.

3A is a schematic diagram showing in detail the channel assignment means 211 in the base station BS1. The channel assignment means 211 comprises means 212 for generating a signal attenuation parameter indicative of the extent to which radio signals are attenuated between the transmitter and receiver under a given connection. The signal attenuation parameter under a given connection between a base station and a mobile station can be generated primarily by sending a measurement signal having a known signal strength from the base station to the mobile station. The mobile station registers the received signal strength and returns the value to the base station, through which a signal attenuation parameter can be calculated. The received signal strength is likely to include the affected portion from other base stations in addition to the transmitted measurement signal corresponding portion. However, most of the received signal strength is due to the transmitted measurement signal. For example, in the case of a mobile wireless network, such signal attenuation measurements are made repeatedly over established or established connections. This is done in a known manner without the support of control channels, and thus the method of operation of the means 212 is not described in detail herein.

The measurement of the signal attenuation parameter has been described with reference to the downlink, that is, the case where a measurement signal is sent from the base station. However, it will be appreciated that the measurement signal may be transmitted from the mobile station, in which case the signal attenuation parameter is measured during the uplink. However, the signal attenuation in the connection can be regarded as almost the same on both the uplink and the downlink, so it is very important to apply the present invention whether the signal attenuation parameter is measured on the uplink or the downlink. Not.

The means 212 generates a connection list 213 in which signal attenuation parameters δ ₁ , δ ₂ , ... for each connection F1, F2, ... are stored. The signal attenuation parameter stored in the connection list 213 constitutes input data to an algorithm used to assign channels to the hopping sequence list according to the method described below. The storage means 214 compares these signal attenuation parameters with each other and stores the connections in one assorted connection list 215 according to these parameters, with the lowest signal attenuation parameter. The links are ordered first in the list of links. For the connection with the lowest signal attenuation parameter the reference m ₀ in the classified connection list, for the second lowest signal attenuation parameter m ₁ , and so on, i.e., the order in which the signal attenuation parameter gradually increases. Add a serial number. In other words, the fact that one connection has a low signal attenuation parameter means that the degree of attenuation at the time of connection is weak, so that the quality of the signal attenuation is good.

The channel assignment unit 211 also includes a channel quality parameter for each frequency-dependent, and for each sequence interval (T _i) is available for each channel, or the channel hopping process, as may be illustrated by the following Examples Means for generating 216. The means 216 will also be described below with reference to FIGS. 3B and 3C (the devices 307a-307c, 407a-407c), and based on the previously generated channel quality parameter values, each means within the channel hopping sequence. sequence also generates interval (T _i) classification by channel list field (KL).

The sorted linked list 215 and the sorted channel lists (307a-307c in FIG. 3B and 407a-407c in FIG. 3C) are sent to the channel hopping sequence generating means 220. The means 220 generates channels and assigns them to the channel hopping sequence, which channels via the control channel (SACCH) (FIG. 2) a list of hopping sequences 201-203 and a mobile station in the base station. Followed by hopping sequence lists 208-210 in MS1-MS3).

The channel hopping sequence generating unit 220 assigns these sequences to each connection in accordance with the principle of allocating a channel hopping sequence including a good channel for connections having a poor quality state. For channels with progressively better quality, channel hopping sequences are assigned that include progressively poorer quality channels. Ideally, all connections will have the same C / I value. Channel assignment for the connection-specific channel hopping sequences may be made by an advanced method as described below.

In short, channel hopping sequences are assigned to the connections according to the principle that for connections represented by a low connection quality, e. For quality connections, multiple channels are represented, which are represented by a lower channel quality, i.e., a higher amount of interference. Another way of saying the same is that the poorer a connection is in terms of attenuation, the better in terms of interference or train channel quality assigned to that connection. Channel assignment for each connection is made with guarantees of orthogonality, ie, multiple connections with the base station do not use the same channel at the same time.

In order to explain the control of the various means included in the present invention in a simple way that is easy to understand, the embodiment shown in FIG. 3A includes a central processing unit (CPU). The CPU in the channel assignment means 211 may communicate with the aforementioned means and control the channel assignment process as described above. The communication is made with the help of a control signal between the CPU and the means, wherein the control signals are located on the CPU and the means as schematically shown in FIGS. 3A-3C. Is transported via bus 222 between ports 212p, 213p, ..., 220p. Due to space concerns, not all ports are numbered in the figures.

Of course, the various equipments used in accordance with the present invention do not need to be controlled from the central processing unit (CPU) in the channel allocation means 211. Each means may have its own software for distributing control in the system by controlling its particular function.

The channel lists 307a-307c on FIG. 3B and 407a-407c on FIG. 3C include channels or frequencies classified by the measured channel quality parameter according to the system in question. This is based on limiting the channel by frequency in FDMA systems and by frequency and timeslot in TDMA systems. In addition, in a TDMA system, channel hopping on a connection means hopping only between channels in one and the same timeslot, ie only hopping between frequencies. In the TDMA system, hopping may be hopping between channels having different timeslots, i.e., side including both frequency and timeslots.

Each channel list may include any channel or frequency that can be used for channel hopping classified according to the measured channel quality parameters. Channel quality parameter is geoniwa will do later with a much measurement, in other words, with reference to Figure 3b, which is determined generation interval (ΔT _k) for each frequency, to the generation interval to form the overall sequence intervals (T _i) or a portion thereof do. That is, if the generation interval under the TDMA system is the time of one timeslot, the channel quality parameter will be measured for each channel.

Here, an embodiment of the means 216 for generating the channel quality parameter will be described in detail with reference to FIG. 3B.

The average value of the frequency channel quality parameters for each frequency f ₁ -f _n is measured through the receiver unit in the water transmitting apparatus 207. x is 1, 2, ..., n. In general, the channel quality parameter indicates channel quality, such as channel interference amount I (t), in a time dependent manner. Exponential x represents frequency.

Other parameters, such as bit error rate or C / I value, can also be measured in relation to the frequency, and the interference value can be calculated from these values. For example, in the case of a mobile wireless network, the measurement of interference at a certain frequency is repeatedly performed by those skilled in the art.

In the case of using a separate receiver, for example, one wideband receiver in measuring the average value of the channel quality parameter, a means for filtering the received wideband signal may be used in order to secure a value for each frequency. . These filters divide the received wideband signals into all frequencies f ₁ -f _n available in the system.

When the signal values secured in measuring the channel quality parameter are squared, the result reflects the strength of the input signal for each frequency f ₁ -f _n .

The means 216 for generating the channel quality parameter may also include a sequence counter 303. The sequence counter 303, a bar, wherein the index (i) displaying the sequence interval (T _i) to the channel hopping sequence is located represents a sequence index.

Each of the time intervals in which the connection is transmitted through a channel occurs in the sequence interval (T _i). That is, as indicated by the first sequence index I1, the first channel in the channel hopping sequence is used over all or part of the first sequence interval T ₁ . Further, the second channel in the channel hopping sequence is used over all or part of the second sequence interval T ₂ , as indicated by the second sequence index I 2, and then proceeds in that fashion. In the present invention, the generation interval ΔT _k constitutes an entire sequence interval, which means that one channel quality parameter is generated for each frequency within each sequence interval range. In the figure, the sequence duration L is 3, and the constant hopping sequence index is i = 1, 2, and 3, respectively.

In the illustrated case, the importance of the generation interval ΔT _k can be illustrated by assuming that the system is a GSM system in which each frequency is divided into eight timeslots, that is, a TDMA frame is formed. Then, the generation interval ΔT _k is time for one TDMA frame.

The receiver unit and the sequence counter 303 in the receiver / transmitter 207 are connected by a multiplexer means 302. The composite device means 302 comprises several connections (three different connections, if shown) between the receiver portion of the water transmission device 207 and the series of average value forming means 304a-c. You can choose one. When the sequence counter 303 displays the sequence index i = 1, a connection from the receiver unit side of the water transmitting apparatus 207 to the first average value forming means 304a is selected, while the sequence counter 303 is selected. Changes the exponent to the sequence index i = 2, and another connection is selected.

Next, it is assumed that the sequence counter 303 displays the sequence index i = 1, where the receiving device section of the water transmitting device 207, as shown in FIG. It is connected to the first average value forming means (304a) through. The means 304a comprises a plurality of averaging filters. The means 304a may also form an average value for each frequency f _x . In forming the mean value, the means for forming the mean value use some form of obvious, non-increasing, nonlinear imaging (e.g., algebraic function) so as to weight different measurements. It may be. When the sequence counter 303 indicates i = 1, that is, while the means 301 is connected to the first mean value generating means 304a, forming an average value over the first generation interval ΔT ₁ . The process can continue. When the first exponent is a frequency (x) and the second exponent at each frequency (f _1- f _n ) is a sequence index (i), the sequence index I = 1 among the channel quality parameters (I ₁₁ -I _n1 ). Are stored in the first channel quality list 305a.

In the present embodiment, the above average value forming means will be described as means for each sequence interval. The average value of the various sequence intervals may be formed by only one average value forming means having the same function as the aforementioned three average value forming means.

The first channel quality list 305a is then classified by the channel quality parameter by the first classification means 306a. As a result of this classification process, the first classified channel list 307a is obtained, the frequency with the least disturbance due to interference, that is, the frequency with the lowest channel quality parameter c ₁₁ and the frequency with the second lowest channel quality parameter. C ₂₁ , etc., where the first exponent represents the frequency order and the second exponent represents the sequence index (i).

The above process is repeated in the same manner as the sequence counter 303 indicates sequence indices i = 2 and i = 3, respectively. Subsequently, when the sequence counter 303 indicates a sequence index i = 2 and i = 3, respectively, the second average value forming means 304b and the third average value forming means 304c are the second and third generation intervals. Each average value is formed during ΔT _2, ΔT ₃ , thereby obtaining channel quality parameters I ₁₂ -I _n2, I ₁₃ -I _n3 for each frequency f ₁ -f _n . The values are stored in the second channel quality list 305b and the third channel quality list 305c, which are classified by respective second sorting means 306b and third sorting means 306c. . As a result, a second classified channel list 307b in which the frequency having the highest channel quality is indicated by c ₁₂ and a third classified channel list in which the corresponding frequency is denoted by c ₁₃ are obtained according to the above-described exponential addition method.

The time constant in the average value forming filters in the average value forming means 304a-304c is preferably in the order of the time scale to the date scale. In other words, the values are collected during this period and their average is formed. That is, the result obtained through the means 216 for generating the channel quality parameter is the sorted channel list 307a-307c for each sequence interval T ₁ -T ₃ . The lists include frequencies f ₁ -f _n classified according to the channel quality parameter value for each frequency within the range of each sequence interval T ₁ -T ₃ .

Since frequencies with high channel quality parameters are only slightly disturbed by interference, those frequencies have high quality related to interference.

In order to be able to measure the amount of interference at each generation interval within the sequence interval range, it is desirable that the interference situation remain unchanged within each sequence interval examined by the system. This preferred situation results in certain conditions for the wireless communication system. That is, the sequence counting should be performed consistently at both the transmitting and receiving sides of the connection. In order to be able to measure the channel quality of frequencies in different sequence intervals (T _i ), the various base stations in the wireless communication system must have the same sequence duration (L). The sequence interval for the base station should not be replaced due to the sequence interval in other base stations. On the other hand, the sequence counters 303 in individual base stations may be in different phases within the channel hopping sequence. That is, the count frequency should be the same, but it is not necessary to change the sequence index at the same time in time.

A modification of the foregoing embodiment of the means 216 for channel quality parameter generation is described with reference to FIG. 3C. The sequence duration is the same as in the previous embodiment, that is, L = 3, and the radio communication system is assumed to be a somewhat modified GSM system. In this case, the generation interval ΔT _k is a time slot time in a TDMA frame. The index k indicates the number of timeslots and assumes k = 1, 2, ..., 8. The means 216 for generating channel quality is, in the present embodiment, i, i = i (k) as a function of timeslots, but as in the previous case, the sequence index i, i.e., the channel hopping sequence. And a sequence counter 403 indicating a sequence interval T _i located.

The composite device means 402, as mentioned above, makes a connection from the receiving device of the water transmitting device 207 to the three average value forming means 404a-404c according to the sequence index displayed through the sequence counter. Choose. That is, the first sequence interval (T ₁₎ while, the number of connections to the transfer device 207 side receives the first mean value forming means (404a) from the apparatus unit the sequence counter 403 indicates sequence index i = 1 Is selected, and no connection to each of the second and third average value forming means 404b, 404c is made.

The sequence counter 403 can count over eight timeslots of k = 1, 2, ..., 8 during a time period in which the first average value forming means 404a is connected to the receiver portion of the water transmission apparatus 207. have. That is, when the sequence counter 403 indicates i = 1, the sequence counter counts eight timeslots k = 1, 2, ..., 8. The sequence counter 403 controls the first average value forming means 404a to form an average value for each generation interval ΔT _k , that is, for each duration of the timeslot k. In this way, the channel quality parameter value for each frequency f1-fn and for each time slot k = 1, 2, ..., 8 for each sequence interval T ₁ -T ₃ is secured. That is, the respective channels (ch1-chn), and by each sequence interval (T ₁ -T ₃₎ for each channel quality parameters are obtained. Channel quality parameters I ₁₁ -I _n1 obtained for the channels ch ₁ -ch n during the first sequence interval T ₁ having the sequence index i = 1 are stored in the first channel quality list 405a. The channel qualities for the second and third sequence intervals T ₂ and T ₃ , where the sequence indices are i = 2 and 3, are also obtained in the same manner. These values (I ₁₂ -I _n2 ), (I ₁₃ -I _n3 ) are stored in the respective second and third channel quality lists 405b, 405c. Each channel quality list 405a-405c is stored in each storage means 406a-406c for each channel quality parameter as measured above. In this way, the respective sequence intervals (T _i) fill the channel list (407a-407c) are generated by each classification. The best channel in each sequence interval range, that is, the channel with the least disturbance, is denoted by c _1i . Lane channels in the list are represented by c _2i ,

In the case of this embodiment, the wireless communication system is not only sequence synchronous, but also time synchronous, i.e., the time slot duration does not change with time. Otherwise, the interference situation in the timeslot may change over time.

The means 220 for generating channel hopping sequences and assigning the corresponding channel hopping sequences on a per connection basis will be described in more detail. It relates to different cases depending on the relevant wireless communication system. As mentioned above, channel hopping may include hopping between frequencies only, hopping between both frequencies and timeslots, and hopping only between timeslots.

The representation channel hopping sequence used below includes a hopping sequence that includes channels defined by frequency in an FDMA system and defined by frequency and timeslot in a TDMA system. The presentation channel hopping sequence relates to hopping sequences that include only frequency. That is, the frequency hopping sequence and the channel hopping sequence are the same as one with respect to the FDMA system.

A channel hopping sequence will be described, taking the case where the wireless communication system is an FDMA system as an example. As previously described with respect to FIG 3b, the generation interval (ΔT _k) constitutes the entire sequence intervals (T _i). This means that the sorted channel lists 307a-307c will include a frequency. In this case, the channel is limited only by frequency. To achieve orthogonality at the base station, only one frequency from each sorted channel list may be included in the channel hopping sequence. Each frequency must maintain their respective sequence index in the channel hopping sequence. That is, the frequency from the channel list 307a with sequence index i = 1 should be used during the first sequence interval T ₁ for sequence index i = 1.

One suitable hopping sequence algorithm selects the highest ranked frequency from each of the classified channel lists 307a-307c, c ₁₁ , c ₁₂ , c ₁₃ , and causes these frequencies to construct the best channel hopping sequence. Do it. Subsequently, the next highest frequencies c ₂₁ and c ₂₂ are selected to form a next order channel hopping sequence, and so on. The three best frequencies with respect to interference then constitute the best channel hopping sequence, while the three worst frequencies also constitute the worst channel hopping sequence.

Another progressive hopping sequence algorithm may be used to ensure a smaller quality difference between the different channel hopping sequences. According to this hopping sequence algorithm, the best frequency c ₁₁ , c _{12 of} the first and second channel lists 307a and 307b and the lane frequency c ₂₃ of the third channel list 307c are the corresponding hopping. Assigned to the sequence algorithm. The lane frequencies c ₂₁ and c _{22 of} the first and second channel lists 307a and 307b and the best frequency c ₁₃ of the third channel list 307c are also assigned to the lane hopping sequence algorithm. This process may be repeated in pairs for the remaining frequencies that are progressively worsening in the channel lists 307a-37c. That is, the third best channel hopping sequence is the third best frequency (c ₃₁ , c ₃₂ ) of the first and second channel lists (307a, 307b) and the fourth best of the third channel list (307c). Is assigned to the frequency of c ₄₃ . The difference between the various channel hopping sequences becomes smaller than in the previous case.

The frequencies included in the channel list may be allocated to the channel hopping sequence in other ways, so that the longer the sequence duration L, the larger the selection.

However, in order to maintain orthogonality at the base station, channel hopping sequence, it may or may not be individual channel list, i.e., one or more frequencies from one and the same sequence intervals (T _i) comprises an absolute. The frequencies in the channel hopping sequence must also retain their sequence index i, i.e., during the first sequence interval T _{1 with} sequence index i = 1, the first channel list 307a for sequence index i = 1 One frequency from C) should be used for the channel hopping sequence.

In certain cases, the selection of frequencies to be assigned to the channel hopping sequence for the connection can be done according to the principles described above, wherein in terms of connection quality, the worst case connection has the best channel hopping sequence for interference. Assigned. The second worst-case connection is also assigned a suboptimal channel hopping sequence, followed by a progressively worse channel hopping sequence order for the progressively good connections.

The generation of the channel hopping sequences will now be described with reference to a TDMA wireless communication system where hopping between timeslots is not allowed. As also mentioned above with reference to 3b, the generation interval (ΔT _k) constitutes the entire generation interval (T _i). Channel hopping in this type of system means changing only the frequency of each connection, that is, hopping is performed only between channels having the same timeslot. In this system form, for example, there are frequency hopping sequences first generated according to the hopping sequence algorithm described above. Then, each timeslot is assigned to each connection, followed by a frequency hopping sequence. The frequency hopping sequence is combined with the timeslots assigned per connection to form one channel hopping sequence, where each channel of the sequence is defined by the same timeslot. As mentioned above, each TDMA frame contains eight timeslots under the GSM system. This means that up to eight connections may use channel hopping sequences having the same frequency hopping sequence, provided that the same timeslot is not assigned for the connections.

Strategies can be made to ensure that as many worst-case connections as possible, i.e., those with the highest signal attenuation parameters, can use the best frequency within each sequence interval. Channel hopping sequences for these connections are within each sequence interval and include different channels, all of which are defined by the same frequency. The channel hopping sequence for a connection to one consists of channels all defined by the same timeslot. For a series of progressively better connections, the use of lane frequencies in the range of each sequence interval is allowed. However, it may be desirable to reserve one or more timeslots that may use the same frequency hopping sequence, thereby making the channel hopping sequences available for future connections.

As also mentioned above the 3b as a reference, the hopping between time slots is permitted, the generation interval (ΔT _k) a sequence interval (T _i) each time the configuration to the channel hopping sequence example for TDMA wireless communication system in which Describe the creation of these fields. Frequency hopping sequences are generated first through the hopping sequence algorithm described above, and then timeslot hopping sequences are generated. The timeslot hopping sequences can also be generated by means of a random number generator. Each frequency hopping sequence is then combined with a time hopping sequence from which channel hopping sequences are formed.

In the case of this embodiment, the frequencies are assigned to the channel hopping sequence for one connection according to the same principles as described above, where the best channel hopping sequence in terms of interference for the worst case connection in terms of connection quality. Is assigned. The second worst connection is assigned a suboptimal channel hopping sequence, followed by the progressively worsening channel hopping sequences for the progressively good connections.

To the TDMA radio communication system, the generation interval (ΔT _k) is for composing a sequence interval (T _i) each time an example will be described with respect to generation of the channel hopping sequence. As previously described with reference to FIG. 3C, the sorted channel lists 407a-407c, in this case, include all frequency / timeslot combinations. That is, the corresponding channels can be used for channel hopping and are classified by the channel quality parameter. Channel hopping sequences are thus generated directly from the channel lists according to the hopping sequence algorithm as mentioned in the first embodiment above.

In the case of the present embodiment, it is possible to generate a channel hopping sequence in which all channels in the sequence are defined by the same timeslot and no hopping between timeslots is allowed.

In this case, the frequencies assigned to the channel hopping sequence or connection may be selected according to the principles described above, where the best channel hopping sequence is assigned in terms of interference for the worst connection in terms of connection quality. . The second worst connection is assigned a suboptimal channel hopping sequence, followed by the progressively declining connections for channel hopping sequences.

In all the cases described above, the means 220 generates a channel hopping sequence for each connection m ₀ -m ₆ by using the aforementioned double spacing. One channel hopping sequence is then used by the base station side generator and the other channel hopping sequence is used by the base station side receiver or each connection. Two of these channel hopping sequences per connection are then stored in each hopping sequence list in the base station, such as the hopping sequence lists 201-203 of FIG. 3. The two channel hopping sequences are also transferred to the mobile station via a control channel (SACCH) and stored in each hopping sequence list, such as the hopping sequence lists 204-206 as shown in FIG.

For simplicity and clarity, a central processing unit (CPU) and ports 212p, 213p, ..., 220p having a bus line 222 are omitted in the following figures.

4 is a schematic diagram showing a second embodiment of the present invention, and relates to the channel assignment means 211. FIG. The sorted channel lists 307a-307c and 407a-407c are generated in a manner different from that described with reference to FIGS. 3A-3C. In the embodiment of Fig. 4, each mobile station MS1-MS3 measures the downlink interference amount I (t). That is, each mobile station MS1-MS3 calculates an average value of the interference amounts for each frequency. These values are then sent to respective means 408a-408c for generating a channel quality list at the base station. The values are also transmitted on the control channel labeled SACCH, as schematically indicated by the dotted line in the figure. The transfer of the registration interference values from the mobile station to the means 408a-408c for generating channel quality in the base station may be accomplished in a known manner with the aid of the transmitter / receiver 207-210. However, for the sake of clarity, individual dotted lines are shown in the drawings.

The embodiment of FIG. 4 includes three mobile stations. The base station comprises means 408a-408c for generating a channel quality list for each mobile station MS1-MS3. One such means 408a-408c may refer to the aforementioned means 302, 303, 304a-304c, 305a-305c in FIG. 3b or the means 402, 403, 404a-404c, 405a-405c in FIG. 3c. Include. Because of the margin, in Figure 4 these means are represented by one single means 408a-408c. That is, each of the means for generating channel quality lists (408a-408c) is to generate a three channel quality lists all, one for each respective sequence intervals (T _i).

The average values are formed from the channel quality list obtained with the help of each means 408a-408c for generating a channel quality list for each sequence interval T ₁ -T ₃ , and the first, second and third classifications. Classified by the means 409a-409c. Average values are formed from the three channel quality lists secured for the first sequence interval T ₁ having a sequence index i = 1 and classified by the first classifying means 409a. The average values formed from the three channel quality lists secured for the second sequence interval T _{2 with} sequence index i = 2 are classified by the second classifying means 409b, and then proceed in this way. In the figure, three input signal paths are shown, one from each of the means 407a-407c for generating the channel quality list, i.e., each of the classification means 409a-409c. Each of the classification means 409a-409c calculates an average value of the channel quality parameter for each frequency / channel and for a sequence interval, and further classifies corresponding frequencies / channels according to the calculated average value.

In forming the average value, the means 409a-409c may use an apparent and constantly increasing form of imaging (eg, algebraic function), which weights different values. Thus, becomes the average value of the values determined as appropriate, and then, the respective sequence intervals (T _i) by the frequency / channel that is classified according to the mean value is formed, that is, the amount of interference increases.

If shown, all measurement data is subject to such in-base processing as average formation and classification. It may be possible for the mobile station to perform some or all of the data processing up to the channel hopping sequence. For example, each mobile station may be provided with respective means 408a-408c, respective classification means 409a-409c and respective classified channel lists 307a-307c or 407a-407c for generating a channel quality list. It may be. In this case, the classified channel list is sent to the base station through a control channel (SACCH).

The remaining means 212-215 and 220-221 operate in the same manner as the embodiment of FIG. 3A, and thus description thereof will be omitted when referring to FIG. 4.

5 is a schematic diagram showing a third embodiment of the present invention, and relates to the channel assignment means 211. FIG. Unlike the previous two embodiments described with reference to FIGS. 3A-3C and 4, the sorted channel lists 307a-307c and 407a-407c are generated from interference measurements for both uplink and downlink, respectively. do. In this case, the amount of downlink interference is measured by each mobile station MS1-MS3 in the same manner as in the description with reference to FIG. 4. The amounts of interference measured for the uplink are also used, which are stored in the channel quality lists 305a-305c in FIG. 3B and the channel quality lists 405a-405c in FIG. 3C. This is accomplished by the means 302, 303, 304a-304c in FIG. 3b and the means 402, 403, 404a-404c in FIG. 3c for generating the channel quality parameter. For ground reasons, the means 302, 303, 304a-304c, 305a-305c in FIG. 3b and the means 402, 403, 404a-404c, 405a-405c in FIG. 3c as one single means 501. Indicates. However, in this case, the first channel quality lists 305a and 405a are connected to the first classifying means 409a for forming the average value and classifying them, and the first classifying means 409a is the principle of the fourth embodiment. Works accordingly. The second and third channel quality lists 305b, 405b and 305c, 405c are connected to the respective second and third sorting means 409b, 409c in the same manner.

This also allows the amount of interference measured during the uplink to be used in calculating the average amount of interference. In FIG. 5, the means 212, 215 on FIG. 3A are shown as a single unit 502 in a ground relationship. That is, the means 502 has a function corresponding to the means 212-215 of FIG. 3A.

6 is a schematic view showing a fourth embodiment of the present invention, and relates to the channel assignment means 211. FIG. Unlike the above embodiments, in the embodiment of FIG. 6, the double spacing is not used in generating the channel hopping sequences. That is, the means 220a generates only one channel hopping sequence per connection, for example, the channel hopping sequence is used for transmission from the base station. The means 220b for generating a channel hopping sequence operates according to the same principle as the means 220a to generate one channel hopping sequence for each connection, and these channel hopping sequences are generated by the means 220a. While channel hopping sequences are used for transmission at the base station, they are used for reception at the base station. The means 220a receives input data relating to the channels from the means 601. This means corresponds to the means 408a-408c, 409a-409c, 307a-307c in FIG. The input data is secured by measuring the amount of interference in the downlink as described with reference to FIG.

The means 220b obtains channel input data from the means 216, as described above with reference to FIGS. 3B and 3C. These input data are secured by measuring the amount of interference in the uplink, as mentioned above with reference to FIGS. 3B and 3C. Since the measured interference amount values of the uplink and downlink are not mixed with each other, as in the description with reference to FIG. 5, completely independent channel hopping sequences can be generated in the constant means 220a-220b, where one The channel hopping sequence of is used for transmission, while the other channel hopping sequence is used for reception at the base station. The hopping sequences are stored in the hopping sequence list 201-203 in a base station, and in the same manner as before, through the control channel (SACCH) to the hopping sequence list 204-206 in a mobile station. Transferred. The means 212-215 on FIG. 3A are represented as single means 502 in FIG. 6 for reasons on the ground. That is, the means 502 serve as the means 212-215 in FIG. 3A.

7 is a flowchart illustrating the inventive channel hopping method.

In the step (700), wherein the channel hopping sequences are divided into sequence intervals (T _i). The duration of the sequence of intervals corresponds to a time between a channel hopping sequence intervals (T _i) within the two-channel hopping.

In step 701, a single attenuation parameter δ is generated for each established connection F1-F3. The single attenuation parameter can also be generated by measuring the attenuation in the uplink and / or downlink of each connection.

In the step 702, a channel quality parameter is generated for each frequency f1-fn and for each generation interval ΔT _{k in} each sequence interval _Ti . 'Each frequency' may be, for example, all frequencies in the base station, all frequencies in the entire wireless communication system, or some of them. The channel quality parameter can be generated by the respective frequency (f1-fn) each, and for each sequence interval (T _i) within the gap created by (ΔT _k) measures the amount of interference in the uplink and / or downlink. Other measurements include the C / I value or the bit error rate (BER), and each sequence interval (T _i ) for calculating the interference amount value for each frequency (f _1- f _n ) and the generation interval (ΔT _k ). Used as input data in range.

The generation interval (ΔT _k) may be full time or part sequence intervals (T _i). The generation interval ΔT _k may be, for example, one time slot duration in a TDMA frame in a TDMA system. In the latter case, a single value of the amount of interference is obtained for each of the channels (ch1-chn), and by each sequence interval (T _i).

In the staff 703, the secured single attenuation parameter values are stored in the connection list 213, and the secured channel quality parameter values are each channel quality list for each sequence interval T ₁ -T ₃ . Stored at 307a-307c and 407a-407c.

In the staff 704, the connections are classified according to a single measured attenuation parameter (attenuation amount) and then stored in the sorted connection list 215. In using the measurements from the uplink or from both uplink and downlink, the average attenuation value per connection is calculated and the connections are classified according to the average value.

In the staff 705, the frequencies / intervals for each sequence interval T ₁ -T ₃ are classified according to the measured channel quality parameter (interference amount), and then the classified channel lists 307a-307c, 407a-407c. In using the measurements from the uplink or from both the uplink and downlink, an average interference value is calculated for each frequency / channel within each sequence interval T ₁ -T ₃ , and the calculated average value The frequencies / channels are classified according to their sequence interval T ₁ -T ₃ .

At step 706, a method for generating a channel hopping sequence is applied, as mentioned above with reference to the means 216 for generating a channel hopping sequence. The respective channel / frequency to be used during each sequence interval in the channel hopping sequence is selected according to its position in the channel list by sequence interval. As described above with reference to FIGS. 3A-3C, an optimal channel hopping sequence is generated in terms of the channel quality parameter for each channel / frequency in each sequence interval range. Channel hopping sequences are then generated with a channel quality that is less than the best channel hopping sequence.

The channel hopping sequences may be used for transmission from the base station or from a mobile station. Corresponding channel hopping sequences for the receiving device may be generated by the aforementioned double spacing. As another possibility, channel hopping sequences for both transmission and reception per connection may be generated through a channel hopping sequence generation method that does not use a double interval. It will be appreciated that the channel hopping sequence used for the base station side transmission is used for reception at the mobile station, while the channel hopping sequence used for the mobile station side transmission should be used for reception at the base station. .

In step 707, a check is made to determine whether to update the channel hopping sequence for the connections F1-F3. If the response is negative, according to choice N, the process is repeated from staff 701 without updating.

If the answer is affirmative, in step 708 following selection (Y), each connection having a poor connection quality in terms of signal attenuation parameters is assigned a channel hopping sequence of good quality in terms of channel quality. Connection-specific channel hopping sequences are assigned. The worst-case connection in terms of the signal attenuation parameter is assigned the best channel hopping sequence in terms of channel quality parameters. For connections with a progressively better order, the channel hopping sequences are assigned in an order of progressive lack. As mentioned above with reference to FIG. 3C, some channel hopping sequences may have the same channel quality. In such a case, channel hopping sequences that include channels with the same channel quality may be allocated for more connections.

At step 709, the channel hopping sequences are stored in hopping sequence lists 201 and 204-206 in the base station and mobile station. The base station includes a hopping sequence list for each connection, and the hopping sequence lists also include respective channel hopping sequences for transmission and reception. The channel hopping sequences for transmission and reception to be used by the mobile station are transferred to each station via the control channel SACCH and stored in each hopping sequence list in the mobile station. The process is repeated after the staff 708, where hopping to the staff 701 occurs.

That is, whether or not to update the channel hopping sequences is determined by, for example, a monitoring process in the staff 707 with the help of the CPU. The channel assignment means 211 will continue to generate "new" channel hopping sequences, whereby the difference between the call quality of the two channel hopping sequences exceeds a preset threshold, or the interference level is a preset value. If exceeding, one new channel hopping sequence may replace the "old" channel hopping sequence. The update need not necessarily be global, i.e., the channel hopping sequence may only be updated for connections where the difference in call quality exceeds a corresponding threshold. Updates may be necessary if new connections are established or if the reception conditions change due to the movement of the mobile station.

The invention is also applicable without continuing to generate the channel hopping sequences. In this case, for example, at the start of the wireless communication system, a set of channel hopping sequences may be generated by the progressive method. As a form of updating later in the wireless communication system, new channel hopping sequences are generated and used for the next update.

As an optional method, the steps 704 and 705 may be skipped so that the information stored in the connection and channel list 213 and 217 is input to the hopping sequence algorithm used in the step 706. You will organize your data. It should be noted that the hopping sequence algorithm, in this case, does not have the function of the algorithm mentioned above.

Since the unclassified connection list and the channel lists are generated respectively, the hopping sequence algorithm must find the channels to be used by itself while simultaneously assigning the corresponding channels to correct the connections. That is, all the hopping sequence algorithms will function according to the principle that the connection which is insufficient in the principle: signal attenuation parameter is assigned a good channel in the channel quality parameter, but the hopping sequence algorithm itself can be applied in several ways.

As an optional example, the hopping sequences in the base station and the mobile station may include only one channel hopping sequence. In this case, a means for generating an additional channel hopping sequence for each connection by using the double interval is included. The means assigns one of the channel hopping sequences to the transmitting apparatus and the other channel hopping sequence to the receiving apparatus.

The wireless communication system in this preferred embodiment is characterized in that in each base station side wireless cover area the available channels are a base orthogonal channel in wireless communication with mobile stations in a given base station cover area. It has been described as including the corresponding base stations used in the form of a hopping sequence. The base station can generally be thought of as a first wireless station, and the mobile station as a plurality of second wireless stations. The available channels in the cover area may be specifically configured to include some channels assigned to the base station, some of the entire channels, or all channels in the corresponding wireless communication system, wherein the signal attenuation parameters are Created per channel.

In addition, some of the embodiments described above may be applied to a mobile switching center (MSC) or a base station switching center (BSC). In this case, a means for securing a function of the aforementioned means is required. do.

Generating the channel quality parameter and / or the signal attenuation parameter does not necessarily mean continuity in physical measurement. The parameters may also be generated based on theoretical values, as in the case of starting the corresponding wireless communication system. This is possible through theoretical calculation models in system design. Channel hopping sequences are then generated according to the reserved values. These channel hopping sequences are used until the corresponding wireless communication system is updated to produce new theoretical values.

Although the figure shows the mobile station by a vehicle, this invention is applicable also to the system in the case of having other types of mobile stations, including a portable.

As described above, the present invention has the effect of maximizing the call quality between the base station and a plurality of mobile stations, so the utility in the relevant industrial field is very high.

Claims (33)

Channel in a wireless communication system (PLMN) comprising at least one first wireless station (BS1) and a second wireless station (MS1-MS3) in which bilateral information is transmitted via signal attenuation and interference (F1-F3). In the channel hopping method according to the hopping sequence, Dividing the channel hopping sequences into sequence intervals (T _i ) that constitute a time required to complete one channel hopping sequence; Generating a signal attenuation parameter (δ) for each of said connections (F1-F3); For each frequency interval (fa-f6) used in the wireless communication system, and for each generation interval (ΔT _k ) including the entire duration of the sequence interval (T _i ) or a part of the sequence interval, each sequence interval ( T _i ) generating a channel quality parameter (I, C / I, BER) in the range; Each sequence interval (T _i) at least one channel hopping generated according to at least one, a group of the channel quality parameter (I, C / I, BER) generating a channel that is connected hopping occurs between them as a star Generating a sequence; Assigning the channel hopping sequences to each connection, made according to the generated channel quality parameters (I, C / I, BER) and the signal attenuation parameters (δ) for the channels included in the hopping sequence. Wow; And channel hopping between the channels included in the channel hopping sequences in wireless communication through the connection between the first wireless station BS1 and the second wireless station MS1-MS3. . The channel hopping sequences of claim 1, wherein the channel hopping sequences are stored in respective hopping sequence lists 201-203 and 204-206 in the first wireless station BS1 and the second wireless station MS1-MS3. How to. The method of claim 1, wherein the channel hopping sequence number within the channel, and the sequence interval the duration is constant inside the wireless communication system, the sequence interval (T _i) the duration of (T _i) is between the two channel hopping Characterized in that it corresponds to time. The method according to any one of claims 1 to 3, wherein the generation interval (ΔT _k ) includes the entirety of the sequence interval (T _i ). The method according to any one of claims 1 to 3, wherein the generation interval ΔT _k is such that the wireless communication system has a channel quality parameter for each sequence interval T ₁ -T ₃ and for each channel ch1-chy. And in the case of a generated TDMA system, the timeslot time in the TDMA frame. The method of claim 4 or 5, wherein the channel hopping sequence generation step, Selecting a channel forming the channel in the channel hopping sequence to be used during the first sequence interval, according to the channel quality parameter values generated within a first sequence interval (T ₁ ); Selecting additional channels according to the channel quality parameter values generated within the remaining sequence interval (T ₂ -T ₃ ). The method of claim 4, wherein the generating of the channel hopping sequence comprises: Within each sequence interval (T ₁ -T ₃ ), select the best channel in terms of the channel quality parameters (I, C / I, BER), in which the channels form one best channel hopping sequence. Making a step; From the remaining channels in each sequence interval (T ₁ -T ₃ ) range to form a channel hopping sequence that is progressively poor in terms of the channel quality parameter compared to the best channel hopping sequence. And there is further included the step of selecting the best channel. The method of claim 4, wherein the generating of the channel hopping sequence comprises: Select the best channels that form one best channel hopping sequence, but select the best channel in the sequence of sequence intervals in terms of the channel quality parameters (I, C / I, BER) Selecting a lane channel within a sequence interval range; Channels that form one lane channel hopping sequence are selected, and the channel quality parameters (I, C / I, BER) are in the range of the corresponding sequence interval included in the best channel hopping sequence. Selecting a channel in a suboptimal lane, and selecting the best channel within the remaining sequence interval range; Selecting from the remaining channels in each sequence interval range, the method comprising selecting progressively inferior channel hopping sequences according to the same principles as applied to the best and suboptimal channel hopping sequences. The method of any one of claims 4 to 6, wherein the wireless communication system is a TDMA system. Within each sequence interval (T ₁ -T ₃ ), select the best frequency in terms of the channel quality parameters (I, C / I, BER) in which the corresponding frequencies form one best channel hopping sequence. Making a step; From the remaining frequencies in each sequence interval (T ₁ -T ₃ ) to form a channel hopping sequence that is progressively poor in terms of the channel quality parameter compared to the best channel hopping sequence. There is a step of selecting the best frequency; And selecting at least one timeslot in the TDMA frame for each frequency hopping sequence, wherein each combination of one timeslot and one frequency hopping sequence forms one channel hopping sequence. Characterized in that the method. The method of claim 4 or 6, wherein the wireless communication system is a TDMA system. Selecting the best frequencies that will form one best frequency hopping sequence, while selecting the best frequency in terms of the channel quality parameters (I, C / I, BER) within multiple sequence interval ranges, Selecting a lane frequency within the remaining sequence interval range; Selecting frequencies for forming one lane frequency hopping sequence, wherein the channel quality parameters (I, C / I, BER) are within the corresponding sequence interval range where the best frequencies are included in the first frequency hopping sequence; Selecting the best frequency in the plane and selecting the best frequency within the remaining sequence interval range; Selecting, from the remaining frequencies within each sequence interval range, progressively poor frequency hopping sequences, in accordance with the same principles as applied to the best and suboptimal frequency hopping sequences; And selecting at least one timeslot in the TDMA frame for each frequency hopping sequence, wherein each combination of one timeslot and one frequency hopping sequence forms one channel hopping sequence. Characterized in that the method. The method according to claim 7 or 8, Classifying the channels (ch1-chy) for each sequence interval (T ₁ -T ₃ ) with respect to the channel quality parameter (I, C / I, BER); And storing the classified channels in a sorted channel list (407a-407c) in which channels according to a sequence interval (T ₁ -T ₃ ) are stored according to the channel quality parameter. The method of claim 9 or 10, Classifying the frequencies f1-f3 for each sequence interval (T ₁ -T ₃ ) with respect to the channel quality parameter (I, C / I, BER); And storing the classified frequencies in a sorted channel list (307a-307c) in which frequencies for each sequence interval (T ₁ -T ₃ ) are stored according to the channel quality parameter. 12. The method of claim 11, wherein the channel selection for each channel hopping sequence is performed according to the sequence of the channels in each of the sorted channel lists (307a-307c, 407a-407c). 13. The method according to claim 12, wherein the frequency selection step for each channel hopping sequence is performed according to the sequence of the frequencies in each classified channel list (307a-307c). 15. The method of any one of claims 7 to 14, wherein assigning channel hopping sequences for each connection comprises: Selecting the worst connection in terms of the signal attenuation parameter [delta]; Assigning a best channel hopping sequence for the worst connection; Selecting connections that become progressively better in terms of the signal attenuation parameter [delta]; Assigning progressively poor channel hopping sequences for the progressively better connections. The method of claim 15, Classifying the connections with respect to the signal attenuation parameter [delta]; Storing the classified connections in a sorted connection list (215) in which the corresponding connections are stored according to the signal attenuation parameter (δ). The method of claim 16, wherein each link (F1-F3) is selected according to a sequence in the sorted linked list (215). 18. The method of claim 16 or 17, wherein the step of generating channel hopping is distinguished from each of the previously generated channel hopping sequences by a double interval, and one channel for each connection (F1-F3) together with the corresponding channel hopping sequence. And generating, by means of said double spacing, a second channel hopping sequence to be a channel hopping sequence pair. The method according to any one of claims 6 to 17, wherein the channel hopping sequence generation step is generated according to the channel quality parameters I, C / I, and BER within a sequence interval range for each channel hopping sequence. Generating two channel hopping sequences for each connection (F1-F3). 20. The method according to claim 18 or 19, wherein the signal attenuation parameter (δ) for each connection (F1-F3) is generated by measuring signal attenuation in the uplink. 20. The method according to claim 18 or 19, wherein the signal attenuation parameter (δ) for each connection (F1-F3) is generated by measuring signal attenuation in the downlink. 22. The method of any one of claims 18 to 21, wherein the channel quality parameter (I, C / I, BER) generation step comprises: an interference amount value, a C / I value, and a bit error rate value (BER) in the uplink. And measuring one. 22. The method according to any one of claims 18 to 21, wherein the channel quality parameter (I, C / I, BER) generation step comprises: an interference amount value, a C / I value, and a bit error rate value (BER) in the downlink. Measuring one; And forming an average value for the same frequency and the same generation interval (ΔT _k ) with respect to the generated channel quality parameter values for each sequence interval (T ₁ -T ₃ ). 22. The method according to any one of claims 18 to 21, wherein the channel quality parameter (I, C / I, BER) generation step includes the interference amount value, the C / I value and the bit error rate value of both the uplink and the downlink. Measuring BER); And forming an average value for the same frequency and the same generation interval (ΔT _k ) with respect to the generated channel quality parameter values for each sequence interval (T ₁ -T ₃ ). 25. The method according to any one of claims 22 to 24, wherein the channel quality parameter (I, C / I, BER) generation comprises measuring the values for every frequency and channel included in the wireless communication system. Method characterized in that. 25. The method of any one of claims 22 to 24, wherein generating the channel quality parameter (I, C / I, BER) comprises: measuring the values for each subset of frequencies and channels included in the wireless communication system; Method comprising a. 25. The method according to any one of claims 22 to 24, wherein the channel quality parameter (I, C / I, BER) generation comprises measuring the values for the corresponding channels and frequencies assigned to the base station. Method comprising a. 28. The method of any one of claims 8-27, wherein assigning the channel hopping sequence to the hopping sequence lists 307a-307c, 407a-407c comprises: assigning one of the paired channel hopping sequences to the base station. Transferring to a hopping sequence list (201-203, 204-206) in BS1 and transferring the other to the mobile station MS1-MS3. 29. The method of claim 28 including transferring said channel hopping sequences to said mobile station (MS1-MS3) side hopping sequence list (204-206) via a control channel (SACCH). A corresponding first wireless station and each second configured, comprising a first wireless station BS1 communicating with at least one second wireless station MS1-MS3 via channels f1-fn, ch1-chy. A device under a wireless communication system in which channel hopping is performed according to channel hopping sequences divided by a series of sequence intervals (T _i ) for signal attenuation and interference between a wireless station (F1-F3). Means 212 for generating a signal attenuation parameter δ for each connection F1-F3; For each of the frequencies (f1-f6), also, the sequence interval (T _i) all or each part thereof different generating intervals (ΔT _k), each sequence interval (T _i) quality of the channel to the extent the parameter (I, C / Means (216) for generating I, BER; Each connection according to the signal attenuation parameter δ previously generated for each connection F1-F3, and according to the channel quality parameters I, C / I, and BER pre-generated for each channel in the channel hopping sequence. means for assigning a channel hopping sequence for (F1-F3), the channel quality parameters (I, C / I, BER ) sequence intervals (T _i) for each channel (f1-fn are selected in accordance with, ch1-chy Means (220) for generating at least one channel hopping sequence for each connection. The method of claim 30, At least one receiving device 207 in the first wireless station BS1, and each mobile station MS1-MS3 for receiving the signal values transmitted to the means 216 for generating a channel quality parameter. At least one receiver 208-210; Means (CPU) for controlling channel hopping in the wireless communication system. The method of claim 31, wherein Means (214) for classifying the connections by the signal attenuation parameter (δ); Means (215) for storing the classified connections in a sorted state according to the signal attenuation parameter (δ). 32. The apparatus of claim 31, wherein the means 216 for generating a channel quality parameter is A sequence counter (303, 403) indicating a sequence interval (T _i ) where the channel hopping sequence is located; Each generation interval (ΔT _k) for the frequency (f1-fn) each of a sequence of intervals form the mean value, and these values from each channel quality parameter measurement value (T _i) according to the channel quality list (305a-305c, 405a- At least one average value forming means (304a-304c, 404a-404c) stored in 405c; Multi-device means 302 for connecting the receiving device 207 with one of a series of mean value forming means 304a-304c, 404a-404c in accordance with the sequence interval T _i indicated by the sequence counters 302, 403. , 402); Classification means for classifying the frequencies (f1-fn) and channels (ch1-chy) according to the channel quality parameters (I, C / I, BER) by the sequence interval (T _i ) in the wireless communication system 306a-306c, 406a-406c; The classification of the frequency (f1-fn) and channels (ch1-chy) for respective sequence intervals by (T _i) means for storing in response to the channel quality parameter (I, C / I, BER ) (307a- 307c, 407a-407c.