RU2287901C1 - Method and device for transmitting subscriber's station services between base stations 0f two different cellular networks of which one has priority relative to other one - Google Patents

Abstract

FIELD: radio engineering; wireless cellular communication systems.

SUBSTANCE: proposed method includes L estimates of signal-to-noise ratio of adjacent priority-network base station in sliding window, their averaging and smoothing to form K smoothed mean values of signal-to-noise ratio which are used to predict time interval T_pr whereupon mentioned value will exceed network input threshold; predicted interval T_pr is compared with maximal interval T_max, and communications are established for subscriber's station with base stations of priority or non-priority networks. Device implementing this method has two flip-flops, signal-to-noise ratio estimating unit, averaging unit, smoothing unit, prediction unit, and logic gates.

EFFECT: enhanced quality and reliability of communications.

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Description

The invention relates to the field of radio engineering, in particular to a method and device for handing off a subscriber station (AC) between base stations (BS) of two different cellular networks, one of which is priority over the second, and can be used in wireless cellular communication systems.

A prerequisite for the effective operation of modern wireless communication systems is to maintain communication when moving a mobile speaker from the service area of one network to the service area of another network.

Transferring AC service between base stations of two different cellular networks is a procedure for managing the flow of transmitted information in wireless communication systems, which ensures that users of the AC maintain communication when moving between networks and when choosing the type of service in the area of overlapping service areas of several networks. This procedure is called intersystem “hand-off” (handoff), for example, K. Pahlavan, P. Krishnamurthy, A. Hatami, M. Ylianttila, J. P. Makela, R. Pichna, Jari Vallstrom. "Handoff in hybrid mobile data networks" IEEE Personal Communication, vol. 7, issue 2, Apr. 2000.

AC service transfer in the fourth generation mobile networks is carried out not only with the aim of maintaining the connection, but also with the aim of providing users with better service and in accordance with their personal requirements. In this case, the AS should automatically decide on the transfer of service, based on the preferences of the user, as well as enable the user to decide on the transfer of service AC manually.

Currently, the procedure for transferring AC service between base stations of two different cellular networks is usually divided into two types: “hard” inter-system transmission and “soft” inter-system transmission of AC service. The “hard” intersystem AS service transfer is based on the principle of “disconnect (AS from the BS of the source network) before connecting (AS from the BS of the new network)”. Thus, with a “hard” intersystem service transfer, the AS is served at only one BS at any given time. There is a certain time interval for a “soft” inter-system handover of an AS, during which the AS is simultaneously served by at least two BSs that participate in the AS handover procedure. In this case, the principle of "connect (speakers with the BS of the new network) before disconnecting (speakers with the BS of the source network)" K. Pahlavan, P. Krishnamurthy, A. Hatami, M. Ylianttila, JP Makela, R. Pichna, Jari Vallstrom. "Handoff in hybrid mobile data networks" IEEE Personal Communication, vol. 7, issue 2, Apr. 2000.

Soft intersystem AC handoff can be performed between neighboring CDMA systems if these systems operate on the same frequency. If it is impossible to perform soft inter-system handover of the AC, a hard inter-system handover of the AC is performed. For example, between CDMA systems with different frequencies.

The intersystem handover procedure is determined by the properties of cellular networks. We can distinguish the following main properties of modern cellular networks that determine the procedure for intersystem transfer of service to speakers.

Different networks support different types of service. When performing the intersystem handover procedure, the speakers take into account the priority of the required service. For example, networks support different data rates. In this case, when performing a handover, priority is given to the data rate. AC handoff priority is higher for networks that support higher data rates. For example, a WLAN network can support a data transfer rate of 2Mbit / s, and a GPRS (General Packet Radio System) can only be from ten to one hundred kbit / s. In this case, the priority from the WLAN to the GPRS system is lower than in the opposite direction. The priority of the network can also be determined by the cost of the services provided, the reliability of the confidentiality of the transmitted data, etc.

AU should provide priority network service as early as possible and maintain priority network service for as long as possible.

The coverage areas of different networks may overlap. In this case, at any time, it is possible to perform intersystem handover of the AC. In this case, the AC service transfer is performed taking into account the priorities of overlapping networks.

A cell or a group of adjacent cells of a priority network may cover only part of the coverage area of a non-priority network. Moreover, the priority network may have cells of various sizes.

Signal strengths of base stations of different networks can vary significantly.

Different networks, as a rule, operate at different frequencies and use various telecommunication technologies (for example, CDMA and OFDM). Therefore, speakers that provide operation in several networks with different frequency ranges and different telecommunication technologies must contain several receivers with the corresponding frequency ranges and supporting the corresponding telecommunication technologies. In this case, the AS can simultaneously receive the BS signals of several networks.

When performing AC handoff between base stations of various cellular networks, in the conditions of fading, a ping-pong effect often occurs, which worsens the quality and reliability of communication. With ping-pong, useless (false) handoffs of speakers between base stations of various cellular networks in the forward and reverse directions occur. The ping-pong effect can occur under fading conditions, both when the signal strength of the base stations changes when the speakers move, and when the position of the speakers changes with respect to the boundaries of the networks. YE Min-hua, LIU Yu, ZHANG Hui-min THE MOBILE IP HANDOFF BETWEEN HYBRID NETWORKS PIMRC 2002, The 13th IEEE International Symposium on Personal, Indoor and Mobile Communications, September 15-18, 2002, Lisboa, Portuga www.ctr.kcl .ac.uk / Private / Mischa / PIMRC2002 / papers / cr1002.pdf.

With an increase in the frequency of the ping-pong effect, such undesirable phenomena as speech impairment during the transmission of voice messages, an increase in the load of the network and processors of all levels (AS, BS, and network level) arise.

Another well-known phenomenon that worsens the quality and reliability of communication during the transfer of AC service between base stations of various cellular networks under fading conditions is the loss of a call that occurs when the AC leaves the service area of the BS of the source network, and the AC maintenance procedure is not completed. Howard G. Ebersman and Ozan K. Tonguz "Handoff Ordering Using Signal Prediction Priority Queuing in Personal Communication Systems" IEEE Trans. Veh. Technol., Vol. 48, no.1, JANUARY 1999.

To increase the capacity of networks, micro and pico cells are used. At the same time, the number of AS service handoffs between base stations of both different cellular networks and one network is increasing in networks. In this regard, it becomes urgent to ensure the reliability of these AC service transfers.

Various methods are known for transferring AC service between base stations of two different cellular networks, for example, the method described in US Pat. No. 5,999816, “Method and apparatus for performing mobile assisted hard handoff between communication systems,” Int. Cl ⁶ . H 04 Q 7/00.

The patent proposes a method and apparatus for a hard intersystem AS service transfer when moving this station between two networks. The BS of the first network determines the base stations of the second network adjacent to the served AC. The list of these BSs and their parameters (signal frequency, signal delay, etc.) the original BS of the first network transmits to the served AS, which receives the pilot BS signals listed in the list, and compares the powers of these pilot signals with the pilot signal threshold. If the threshold is exceeded, then decide that the transfer of service AC is successful. Otherwise, the total power of the signals in the received AC frequency band is compared with the threshold of the total power. If the threshold is exceeded, then decide that the neighboring BS of the second network is not included in the list. Otherwise, the AC service transfer is considered failed, and the AC is served by the original BS. If the threshold of total power is exceeded, then the AS searches for the neighboring BS of the second network. If a neighboring BS of the second network is detected, then a decision is made that the AC handover is successful.

If the transfer of the AC service did not take place, then information received during the attempt to transfer the service (parameters of the base stations of the new network: frequency, delay and signal strength, etc.) is stored on the AC, and with some delay and taking into account the information received during the previous transmission attempt service, perform the following attempt to transfer the service AC.

One of the possible implementations of the considered method of transferring AC service between base stations of two different cellular networks is a device that is part of the AC and consists of a pilot signal energy accumulator and a total signal energy accumulator in the reception band, pilot signal energy and total energy comparison circuits with predetermined thresholds, made in software on the processor, and the pilot signal search unit.

In this patent, to perform a service transfer, the AC of the first network determines the base stations of the second network adjacent to the served AC, and the list of these BS transmits to the served AC, which receives the pilot BS signals in the list and compares the powers of these pilot signals with the pilot signal threshold . If the threshold is exceeded, then decide that the transfer of service AC is successful. Under fading conditions, a ping-pong effect arises, in which false handoffs are performed between the base stations of the first and second networks in the forward and reverse directions.

Another known method of transferring AC service between base stations of two different cellular networks is described in an article by K. Pahlavan, P. Krishnamurthy, A. Hatami, M. Ylianttila, J.P. Makela, R.Pichna, Jari Vallstrom. "Handoff in hybrid mobile data networks" IEEE Personal Communication, vol. 7, issue 2, Apr. 2000.

At the AS served by the BS of the non-priority network, the detection of the neighboring BS of the priority network is performed. When a neighboring BS of a priority network is detected, the AS disconnects from the BS of the non-priority network and establishes communication with the BS of the priority network.

After establishing communication between the AU and the BS of the priority network, the signal strength of the BS of the priority network with a predetermined threshold is compared to the AS. If the signal power of the BS of the priority network is less than the threshold for a given time interval, then the neighboring BS of the non-priority network is determined at the AS, disconnects from the BS of the priority network and establishes communication with the BS of the non-priority network.

In this method, a “hard” intersystem AS service transfer is performed immediately upon detection of a neighboring BS of a priority network. In fading conditions, this leads to the appearance of the “ping pong” effect.

The closest technical solution (prototype) to the claimed invention is the method described in the article YE Min-hua, UN Yu, ZHANG Hui-min THE MOBILE IP HANDOFF BETWEEN HYBRID NETWORKS IEEE Personal Indoor and mobile Communication (PIMRC 2002)).

Before the transfer of service to the AS between the base stations of two different cellular networks on the AS served by the BS non-priority network, determine the neighboring BS priority network.

On comparing the AC power signal priority BSs neighboring network F _with a threshold input to P _Rin network.

If the signal power of a neighboring BS of a priority network does not exceed the threshold for entering the network P _I or exceeds for a time less than T _I , then the signal strength of a neighboring BS of a priority network is compared with the threshold of entering the network P _I until the signal of the neighboring BS priority network exceeds the entry threshold into the _Rin network F for a time greater than a predetermined time T _in the interval.

If the power of the neighboring BSs priority network signal input exceeds a threshold P _Rin network for a time greater than a predetermined time T _in the interval, the AC to communicate with only the BS priority network.

After establishing a connection between the AU and the BS of the priority network, the signal strength of the BS of the priority network is compared with the exit threshold P _out .

If the signal power of the BS of the priority network is less than the threshold for leaving the network P _o for a time longer than the specified time interval T _o , then the speakers only communicate with the BS of the non-priority network.

If the power of the signal of the BS of the priority network is greater than the threshold of exit from the network P _o or less for a time shorter than the specified time interval T _o , then the speaker again compares the power of the signal of the BS of the priority network with the threshold of exit from the network P _o until the signal power The BS of the priority network will be less than the threshold for exiting the network P _o for a time longer than the specified time interval T _o .

The article describing the prototype method does not describe the device that implements this method. However, according to the algorithm described in the description, it is possible to imagine a device that implements the prototype method. One possible implementation based on well-known building blocks is shown in FIG.

The device (figure 1) contains the first 1 and second 2 comparison blocks with a threshold, the first 3 and second 4 logic gates And, the first 5 and second 6 counters, a clock 7, the first 8 and second 9 triggers, while the inputs of the first 1 and the second 2 comparison blocks with a threshold are combined, forming the first input of the device — an input of the signal strength of the signal of the BS of the priority network, the output of the first comparison block with threshold 1 is connected to the first input of the first logical element And 3, the output of the second comparison block with threshold 2 is connected to the first input second logical about element And 4, the second inputs of the first 3 and second 4 logical elements And are combined to form the second input of the device is the input signal detection BS priority network, the output of the first logical element And 3 is connected to the first input of the first counter 5, the output of the second logical elements And 4 is connected with the first input of the second counter 6, the second inputs of the first 5 and second 6 counters are combined and connected to the output of the clock generator 7, the output of the first counter 5 is connected to the first inputs of the first 8 and second 9 triggers, the output of the second counter 6 connected to the second inputs of the first 8 and second 9 triggers, the output of the first trigger 8 is the first output of the device - the output of the signal to establish communication with the BS of a non-priority network, the output of the second 9 trigger is connected to the third input of the second logical element And 4 and is the second output of the device is the signal output establishing communication with the BS priority network.

Implement the prototype method as follows (figure 1).

After determining the AC of the neighboring BS of the priority network, the detection signal of the BS of the priority network and the signal strength of the signal of the BS of the priority network are supplied to the AC transmission device.

The first comparison unit with a threshold 1 compares the signal strength priority BSs neighboring network input threshold of P _Rin network.

If the signal power of the neighboring BS of the priority network exceeds the threshold for entering the network P _I , the output signal of the first comparison unit 1 through the first logical element And 3 is supplied to the first input of the first counter 5 and turns it on. If the power of the neighboring BSs signal priority network exceeds the threshold input of P _Rin network for a time equal to or greater than a predetermined time T _in the interval, then the first counter 5 outputs received signal that sets the first flip-flop 8 in the "zero state", and the second trigger 9 into a "single state". Thus, at the output of the second trigger 9, a signal is established for establishing communication with the BS of the priority network (level of "logical unit"), and at the output of the first trigger 8, the level of "logical zero" is formed. The generated signals from the outputs of the first 8 and second 9 triggers are received respectively at the first and second outputs of the device.

The output signal of the second trigger 9 is supplied to the third input of the second logical element And 4. If the signal power of the BS of the priority network is less than the exit threshold of the network P _o , then the first input of the second logical element And 4 receives the signal from the output of the second comparison unit with threshold 2. When this output of the second logical element And 4 receives a signal at the first input of the second counter 6 and turns it on. If the signal power of the neighboring BS of the priority network is less than the threshold for exiting the network P _o during the time interval T _o , then a signal is output from the output of the second counter 6, setting the first trigger 8 to "single state" and the second trigger 9 to "zero state". Thus, at the output of the first trigger 8, a signal is established for establishing communication with a BS of a non-priority network (level of "logical unit"), and at the output of the second trigger 9, a level of "logical zero" is formed. The generated signals from the outputs of the first 8 and second 9 triggers are sent to the first and second outputs of the device, respectively.

The threshold of entry into the network P _I must meet conflicting requirements. To reduce the frequency of the “ping-pong” effect, it needs to be increased (the higher the signal power of the neighboring BS of the priority network, the lower the probability of a reverse transition), and to reduce the delay of the transmission of the AC service from the BS of the priority network to the BS, the network entry threshold must be reduced ( the earlier the transition begins, the longer the speaker will work in the priority network). In this case, some compromise solution is chosen. Therefore, the prototype method in the conditions of fading does not allow you to effectively deal with "ping-pong."

The exit threshold of the network P _o should also satisfy conflicting requirements. To reduce the frequency of the “ping-pong” effect, it is necessary to reduce it, the lower the signal power of the neighboring BS of the priority network, the lower the probability of a reverse transition. At the same time, in the conditions of fading, the signal of the BS of the priority network can decrease to such a value that it will be lost before the completion of the AC service transfer. Howard G. Ebersman and Ozan K. Tonguz "Handoff Ordering Using Signal Prediction Priority Queuing in Personal Communication Systems" IEEE Trans. Veh. TechnoL, vol. 48, no.1, JANUARY 1999. That is, in the conditions of fading, the probability of signal loss increases. In this case, some compromise solution is also chosen. Therefore, the prototype method in the conditions of fading does not allow you to effectively deal with "ping-pong."

The problem to which the claimed invention is directed is to improve the quality and reliability of communication during AS service transfer, which is achieved by reducing the AS service transmission frequency from the original BS to the neighboring and vice versa (reducing the frequency of the ping-pong effect) and reducing the probability of signal loss in terms of fading.

The problem is solved by the claimed method of handover of a subscriber station between base stations of two different cellular networks, one of which is a priority in relation to the second, in which a neighboring base station of a priority network is determined at a subscriber station served by the source base station of the non-priority network, which consists in , what

on the speakers in a sliding window, L estimates of the signal-to-noise ratio of the neighboring BS of the priority network are averaged, averaged and smoothed, forming K smoothed average signal-to-noise ratios of the neighboring BS of the priority network,

By smoothed by the average values of the signal / noise neighbor BS priority network predicting the time interval T after which the _straight moving average value of the signal / noise ratio exceeds a threshold input network signal / noise ratio _Rin,

if the predicted interval T _pr is equal to or greater than the specified maximum interval T _mak , then the sliding window is successively shifted by one of the L estimates of the signal-to-noise ratio of the neighboring BS of the priority network to the speakers and the time interval T _{pr is} predicted at each shift, after which the smoothed average value signal / noise ratio exceeds a threshold input network signal / noise ratio _Rin, as long as the predicted interval T _ave is less than T _poppy

if the predicted interval T _pr less than the specified maximum interval T _pop , then the speakers establish communication with the neighboring BS priority network and communicate simultaneously with the base stations of priority and non-priority networks,

on the AC, the smoothed average signal-to-noise ratio of the neighboring BS of the priority network is compared with the communication threshold with the BS of the priority network of signal-to-noise _ps and continue to form K smoothed average values of the signal-to-noise ratio of the neighboring BS of the priority network,

By smoothed by the average values of the signal / noise neighbor BS priority network predicting the time interval T, _etc., after which the mean value of the signal / noise ratio exceeds the entry threshold into the network signal / noise ratio _Rin,

if the prediction time interval T _ave is equal to or greater than a predetermined maximum interval T _poppy prediction, the AC to communicate with the BS non-priority network,

if the smoothed average signal-to-noise ratio of the neighboring BS of the priority network exceeds the communication threshold with the BS of the priority network signal / noise _ps , then the speakers communicate with the BS of the priority network,

if the AS is in communication with the BS of the priority network, then continue to compare the smoothed average signal-to-noise ratio of the BS of the priority network with the threshold of communication with the BS of the priority network signal / noise _ps ,

if the smoothed average signal-to-noise ratio of the signal of the neighboring BS of the priority network is less than the threshold of communication with the BS of the priority signal-to-noise network _ps , then the speakers establish communication with the BSs of the neighboring non-priority network and communicate simultaneously with the base stations of the priority and non-priority networks.

The problem is also solved by the claimed transmission service of the subscriber station between the base stations of two different cellular networks, one of which is priority over the second, containing the first and second blocks of comparison with a threshold, a logical element And, the first and second triggers, the outputs of which are respectively the first and the second outputs of the device according to the invention are introduced:

Signal-to-noise ratio estimation unit,

Averaging block,

Smoothing block.

Prediction block,

The first, second and third logical elements OR,

the first input of the logical element And is the first input of the device - the signal input of the base station of the priority network, the second input of the logical element And is the second input of the device - the input of the detection signal of the base station of the priority network, the output of the logical element And is connected to the input of the signal / noise ratio estimator , the first and second outputs of which are connected respectively to the first and second inputs of the averaging block, the output of which is connected to the input of the smoothing block, the output of which is connected to the inputs of the block prediction and the second comparison unit with a threshold, the output of the forecasting unit is connected to the input of the first comparison unit with a threshold, the first output of which is connected to the first input of the first logical element OR, the second input of the first logical element OR, the first input of the second logical element OR and the third input of the averaging block combined, forming the third input of the device, which is the input of the initial setup signal, the output of the first logical element OR is connected to the first input of the first trigger, forming a signal at the output l to maintain communication with the base station of the priority network, the second input of the first trigger is connected to the output of the third OR logic element, the first input of which is connected to the second output of the first comparison unit with a threshold, the second input of the third logical element OR and the first input of the second trigger are connected to the first output of the second block comparison with a threshold, the second output of which is connected to the second input of the second logical element OR, the output of which is connected to the second input of the second trigger, which forms the output signal support and communication with the base station non-priority network.

The inventive method of handover of a subscriber station between base stations of two different cellular networks, one of which is a priority over the second, compared with the known technical solutions in the art found during the search, has novelty and non-obviousness, which consist in a sequence of actions, providing simplified forecasting of the time of the AC movement to the cell boundary of the priority network, establishing communication with the BS of the neighboring priority network and supporting communication of the same belt with base stations of priority and non-priority networks, if the predicted travel time SS to the cell boundary (interval T _ave) is smaller than a predetermined maximum time interval T _poppy, supporting communication both with the base stations of priority and non-priority networks until signal / noise ratio (S / N ) of the neighboring BSs priority network becomes larger than the threshold communication only with the BS priority network signal / noise ratio, _etc., supporting communication with the BS priority network if the moving average signal / noise ratio neighbor BS priority network exceeds the threshold of communication with the BS of the priority network signal / noise _ps , and the establishment of communication with the BS of the neighboring non-priority network and communication support simultaneously with the base stations of the priority and non-priority networks, if the average signal-to-noise signal of the neighboring BS of the priority network is less than the threshold of communication with the BS of the priority network signal / noise _ps .

These features make it possible to reduce the frequency of the “ping-pong” effect and the likelihood of signal loss, which leads to an increase in the quality and reliability of communication during the transfer of AC service between base stations of two different cellular networks.

The inventive device implements all of the features listed in the formula of the features of the proposed method and, compared with the known technical solutions in the art found during the search, has novelty and non-obviousness. According to the invention, a signal-to-noise ratio estimation unit, an averaging unit, a smoothing unit, a prediction unit, first, second and third logical elements OR, as well as new communications, respectively, which improve the quality and reliability of communication when transferring AC between basic stations of two different cellular networks.

Further, the description of the invention is illustrated by examples and drawings.

Figure 2 shows graphs of changes in the signal-to-noise ratio of the BS of the priority network on the AS as it approaches the BS of the priority network.

Figure 3 - graphs of the signal-to-noise ratio of the BS of the priority network on the AS when it moves along the cell boundary of this BS.

Figure 4 is a graph diagram of the states of the speakers and the transitions between them.

Figure 5 is a structural diagram of a speaker.

6 is a structural diagram of the inventive device transfer service AC between the BS of two different cellular networks, one of which is priority over the second.

7 is a structural diagram of the averaging unit.

On Fig is a structural diagram of a prediction block.

The subscriber station (Fig. 5) is shown as an example of execution and comprises an antenna 10, a splitter 11, a signal receiver of a BS of a non-priority network 12, a transmitter 13, a signal receiver of a BS of a priority network 14 and a control unit 15 comprising a control unit 16 and a handover unit of a subscriber station 17, while the first input and output of the antenna 10 are respectively the input and output of the device, the second input and output of the antenna 10 are connected respectively to the first input and the first output of the splitter 11, the second and third outputs of the splitter 11 are connected to responsibly, with the first inputs of the BS signal receiver of the non-priority network 12 and the BS signal receiver of the priority network 14, the output and the second input of the BS signal receiver of the non-priority network 12 are connected respectively to the first input and the first output of the control unit 16, forming respectively the first input and output of the control unit 15, the second and third inputs of the control unit 16, forming respectively the second and third inputs of the control unit 15, are connected respectively to the first and second outputs of the signal receiver BS of the priority network 14, the second input One of which is connected to the second output of the control unit 16, which respectively forms the second output of the control unit 15, the third, fourth, and fifth outputs of the control unit 16 are connected respectively to the first, second, and third inputs of the AC transmission service unit 17, the first and second outputs of which are connected respectively to the fourth and fifth inputs of the control unit 16, the sixth and seventh outputs of which, respectively forming the third and fourth outputs of the control unit 15, are connected respectively to the first and second inputs of the transmitter 13, you od which is connected to the second input 11 of the splitter.

The inventive transmission service of the subscriber station between the base stations of two different cellular networks, one of which is priority over the second, (Fig.6) contains the first 1 and second 2 blocks of comparison with the threshold, logical element And 3, the first 8 and second 9 the triggers, the outputs of which are respectively the first and second outputs of the device, according to the invention further comprises a signal to noise ratio estimation unit 18, an averaging unit 19, a smoothing unit 20, a prediction unit 21, a first 22, a second 23 and a third 24 l logical elements OR, with the first input of the logical element And 3 is the first input of the device, the second input of the logical element And 3 is the second input of the device, the output of the logical element And 3 is connected to the input of the signal-to-noise ratio estimator 18, the first and second outputs of which are connected respectively, with the first and second inputs of the averaging block 19, the output of which is connected to the input of the smoothing block 20, the output of which is connected to the inputs of the prediction block 21 and the second comparison block with threshold 2, the output of the block is predicted 21 is connected to the input of the first comparison unit with threshold 1, the first output of which is connected to the first input of the first logical element OR 22, the second input of the first logical element OR 22, the first input of the second logical element OR 23 and the third input of the averaging block 19 are combined to form a third the input of the device, the output of the first OR gate 22 is connected to the first input of the first trigger 8, the second input of which is connected to the output of the third OR gate 24, the first input of which is connected to the second output of the first block with threshold 1, the second input of the third logical element OR 24 and the first input of the second trigger 9 are connected to the first output of the second comparison unit with threshold 2, the second output of which is connected to the second input of the second logical element OR 23, the output of which is connected to the second input of the second trigger 9.

The structural diagram of the averaging block 19 (Fig. 7) is given as an example of execution and contains the first 25 and second 26 logical gates OR, the first 27 and second 28 registers, the adder 29, the divider 30, the first 31 and second 32 triggers, the first 33 and second 34 logical elements AND, counter 35 and clock generator GTI 36, while the first input of the first logical element OR 25 is the first input of the averaging unit 19, the output of the first logical element OR 25 is connected to the first input of the first register 27, the second input of which is connected to the output of the second logical of the first OR element 26, the output of the first register 27 is connected to the first input of the second register 28 and the second input of the first logical element OR 25, the outputs of the second register 28 are connected to the inputs of the adder 29, the output of which is connected to the input of the divider 30, the output of which is connected to the first input of the first gate AND 33, the output of which is the output of the averaging block 19, the second input of the first gate AND 33 is connected to the output of the first trigger 31, the first input of which is combined with the first inputs of the second gate OR 26, Chick 35 and the second trigger 32, the second input of the first trigger 31 is connected to the first output of the counter 35, the second input of which is combined with the first input of the second logical element And 34 and connected to the output of the GTI 36, the input of which is the third input of the averaging block 19, the second output of the counter 35 is connected to the second input of the second trigger 32, the output of which is connected to the second input of the second logical element AND 34, the output of which is connected to the second inputs of the second logical element OR 26 and the second register 28.

The block diagram of the prediction block 21 (Fig. 8) is given as an example of execution and contains a prediction node 37, a comparison node with a threshold 38, a logic element AND 39, a counter 40 and a multiplier 41, while the input of the prediction node 37 is the input of the prediction block 21, the output the prediction node 37 is connected to the input of the comparison node with a threshold 38, the first output of which is connected to the input of the counter 40, the output of which is connected to the input of the multiplier 41, the output of which is connected to the second input of the AND gate 39, the first input of which is connected to torym comparison output node with threshold 38, and the output of NAND gate 39 is the output 21 of the prediction block.

The inventive method of transferring service to the AC between the BS of two different cellular networks, one of which is priority over the second, is performed as follows.

At the AS, the AS travel time to the cell boundary of the priority network when it approaches the BS of the priority network.

Predicting the time the AC moves to the cell boundary of the priority network is a complex task. The inventive method uses a simplified procedure for predicting the time the AC moves to the cell boundary of the priority network. It can be considered approximately that the AS has approached the cell boundary of the priority network if the smoothed average S / N ratio of the BS of the priority network is equal to some specified value (the signal-to-noise input threshold of the network I / _O ). Then the time of the AC movement to the cell boundary of the priority network will be determined by the time when the predicted S / N ratio of the BS of the priority network is greater than some predetermined value (the threshold of the signal / noise input to the network _in ).

If the travel time of the AC to the cell border of the priority network is approximately equal to the time required to establish communication between the AC and the BS of the priority network, the communication with the neighboring BS of the priority network is established and the communication is maintained simultaneously with the base stations of the priority and non-priority networks.

To predict the travel time of the speakers to the cell border of the priority network, L estimates of the S / N ratio of the neighboring BS of the priority network are performed on the speaker in a sliding window, averaged and smoothed, forming K smoothed average values of the S / N ratio of the neighboring BS of the priority network.

Assessment of the S / N ratio can be performed in various ways. One possible method is the method described in US Pat. No. 6661832, "System and method for providing an accurate estimation of received signal interference for use in wireless communications systems", Int. Cl. ⁷ H 04 B 1/707 or in patent WO 02/17531 "SIR measure method and apparatus for the same".

Averaging L estimates of the S / N ratio can be performed by averaging them in another, smaller sliding window of size J (J <L). The first average value is calculated by averaging in the window the size J of the first J from L values of the S / N ratio. Then a window of size J is shifted by one of L values and the average value is calculated, etc.

Smoothing the average values of the S / N ratio can be performed by various methods, for example, by digital filtering, cubic interpolation, etc. However, from the point of view of practical implementation and the amount of computational cost (for example, on a microprocessor), cubic interpolation is most preferable. Cubic interpolation is described in the book of L.I. Turchak. Fundamentals of numerical methods. Moscow, Nauka, 1987, chapter 2.

According to the smoothed average value of the ratio S / N neighboring BSs priority network predicting the time interval T, _etc., after which the smoothed mean value of S / N ratio exceeds the entry threshold into the signal / noise ratio _Rin network.

Predict time interval T, _etc., after which the moving average value S / N exceeds the threshold input network signal / noise ratio _Rin possible by predicting the sequence of equally spaced from each other values of the ratio C / W (as, for example, in U.S. Patent US №6426971 B1 “System and method for accurately predicting signal to interference and noise ratio to improve communications system performance”, Int. Cl ^7. H 04 B 17/00) and comparing them with a threshold. The time interval T, _etc., after which the moving average value of the ratio S / N exceeds the threshold input network signal / noise ratio _Rin, is equal to the repetition period of the predicted values of the ratio S / N times the number of values of the ratio C / N does not exceed the threshold.

If the predicted interval T _ave is equal to or greater than a predetermined maximum interval T _poppy, then SS sequentially shifted sliding window on one of the L count ratio S / N neighboring BSs priority network averaged and smoothed L estimates, forming K smoothed average values of the ratio S / N the neighboring BS of the priority network, and according to these K values at each shift, the time interval T _{pr is} predicted, after which the smoothed average C / N value will exceed the network entry threshold until the predicted interval T _pr is less than T _max .

If the predicted interval T _{pr is} less than the specified maximum interval T _pop , then the speakers establish communication with the BSs of the neighboring priority network and communicate simultaneously with the base stations of the priority and non-priority networks.

Figures 2 and 3 illustrate the prediction time interval T _ave procedure, after which the smoothed average value of the S / N ratio exceeds the entry threshold into the signal / noise ratio _Rin network.

Figure 2 shows graphs of changes in the signal-to-noise ratio of the BS of the priority network on the AS when it approaches the BS of the priority network. Figure 2 are designated: T _out - the interval of the sliding window, wherein L is evaluated values of the ratio S / N neighboring BSs priority network T _ave - a time interval during which the predicted value of S / N ratio exceeds the entry threshold into the network signal / noise ratio _Rin, T _poppy is the maximum interval.

Figure 3 shows graphs of the signal-to-noise ratio of the BS of the priority network on the AS when it moves along the cell boundary of this BS.

When driving AC along the border of the cell the BS priority network time interval T, _etc., after which the moving average value S / N ratio exceeds the entry threshold into the network signal / noise ratio _Rin is significantly larger than the maximum interval T _poppy, which is approximately equal to the time required to establish communications AU with BS priority network. In this case, the AS communicates with the BS of a non-priority network.

When approaching the cell boundary to AU priority network (2) smoothed average value of C / N exceeds the threshold input network signal / noise ratio _Rin a time interval T, _etc., the smaller the maximum interval T _max. In this case, the AS establishes communication with the neighboring BS of the priority network and communicates with the BS of the priority and non-priority networks.

At the AC, the smoothed average S / N ratio of the neighboring BS of the priority network is compared with the communication threshold with the BS of the priority network (S / N) _ps and continue to average and smooth L current estimates of the S / N ratio, forming K smoothed average values of the S / N ratio of the neighboring BS priority network.

According to the smoothed average value of the ratio S / N neighboring BSs priority network predicting the time interval T, _etc., after which the mean value of S / N ratio exceeds the entry threshold into the signal / noise ratio _Rin network.

If the predicted interval T _ave is equal to or greater than a predetermined maximum interval T _poppy, then SS communicate with the BS non-priority network.

If the smoothed average S / N ratio of the neighboring BS of the priority network exceeds the threshold of communication with the BS of the priority network (S / N) _ps , then the speakers communicate with the BS of the priority network.

If the AU communicates with the BS of the priority network, then they continue to compare the smoothed average S / N ratio of the BS of the priority network with the threshold of communication with the BS of the priority network signal / noise _ps .

If the smoothed average S / N ratio of the signal of the neighboring BS of the priority network is less than the threshold of communication with the BS of the priority signal-to-noise network _ps , then the communication with the BSs of the neighboring non-priority network is established on the AS and the communication is maintained simultaneously with the base stations of the priority and non-priority networks.

Figure 4 shows a graph diagram of the state of the speaker and the transitions between them. A speaker can be in three states: a speaker communication with a BS of a non-priority network, a speaker communication with the base stations of two networks, a speaker communication with a priority network BS. Transitions between these states is determined by the relationship between the predicted interval T _ave and the maximum interval T _poppy, as well as the magnitude of the smoothed average ratio S / N neighboring BSs relative to the threshold priority network communicating with the BS priority network signal / noise _ps.

In the prototype method, in order to reduce the frequency of the ping-pong effect, when transferring the AC service from a BS of a non-priority network to a BS of a priority network, a time interval T _{I is} introduced during which the signal power of a neighboring BS of a priority network must be greater than the threshold for entering the network P _I. However, the introduction of the time interval T _I increases the duration of the transmission service AC from the BS non-priority network BS priority network. This may lead to a delay in the transmission of the AC service from the BS of the non-priority network to the BS of the priority network. In this case, the transmission time of the AC from the BS of a non-priority network to the BS of the priority network can be comparable with the time spent by the AC in the cell of the priority network. This situation can be observed in microcells at high speed speakers. In this case, in the conditions of fading, the probability of signal loss increases.

In the proposed method, the AS predicts the time the AS moves to the cell boundary of the priority network when it approaches the BS of the priority network.

If the travel time of the AC to the cell border of the priority network is approximately equal to the time required to establish communication between the AC and the BS of the priority network, the communication with the neighboring BS of the priority network is established and the communication is maintained simultaneously with the base stations of the priority and non-priority networks.

AU movement time forecasting to priority network cell boundary and communication support simultaneously with base stations a priority and non-priority network, while S / N ratio neighbor BS priority network becomes larger than a threshold communication only with the BS priority network signal / noise, _etc., can reduce the effect of fading on transmission serving the speakers from the non-priority network BS to the priority network BS and reducing the frequency of the “ping-pong” effect. At the same time, the duration of the AS service transfer from the non-priority network BS to the priority network BS and the probability of signal loss are not increased.

In the prototype method, in order to reduce the ping-pong frequency, when transferring AC service from a BS of a priority network to a BS of a non-priority network, a time interval T _{o is} introduced during which the signal power of the neighboring BS of the priority network must be less than the exit threshold of the network P _o . However, the introduction of the time interval T _o increases the duration of the transmission service AC from the BS of the priority network to the BS of a non-priority network. In this case, the signal of the BS of the priority network may decrease to such a value that it will be lost until the completion of the transfer of service to the AC. That is, in fading conditions, the probability of signal loss increases.

In the proposed method, the time required for the AC to reach the AC boundary of the cell of the priority network when it is removed from the BS of the priority network is predicted at the AS.

If the time required to reach the AS of the cell border of the priority network will be approximately equal to the time of establishing communication between the AS and the BS of a non-priority network, then the speakers will establish communication with the BS of a neighboring non-priority network and communicate simultaneously with the base stations of the priority and non-priority networks.

Predicting the time required to reach the AS of the cell boundary of the priority network when it is removed from the BS of the priority network, and the support of communication simultaneously with the base stations of the priority and non-priority networks can reduce the influence of fading on the transfer of AC services from the BS of the priority network to the BS of the non-priority network and reduce the frequency of the effect Ping pong. At the same time, the duration of the AS service transmission from the BS of a non-priority network to the BS of the priority network and the probability of signal loss are not increased.

Figure 5 shows the structural diagram of the speaker, which determines the location of the transmission device in the composition of the speaker and the interaction of this device with other units.

When performing a handover of an AS between base stations of two different cellular networks on an AS served by a source BS of a non-priority network, the receiver of the signals of the BS of the priority network 14 by the signal received from the antenna 10 through the splitter 11 performs the procedure of determining the neighboring BS of the priority network (search for the nearest base stations corresponding network and determining the BS with the highest power).

If the BS of the priority network is detected, then from the first and second outputs of the receiver of the signals of the BS of the priority network 14, the second and third inputs of the control node 16 respectively receive the detection signal of the BS of the priority network, which is generated by the receiver 14 when a BS signal of the priority network is detected, and the signal of the BS of the priority network .

From the third, fourth and fifth outputs of the control unit 16, the first, second and third inputs of the handover unit AC 17 receives the detection signal of the BS of the priority network, the signal of the BS of the priority network and the initial setting signal.

The AC 17 handoff node determines the organization of communication between the AC and base stations of the priority and non-priority networks (support for communication with the BS of the priority network, support for communication with the BS of the non-priority network, simultaneous support for communication with the base stations of the priority and non-priority networks).

If the AU communicates with a BS of a non-priority network, from the first output of a handover unit AC 17, a signal for establishing communication with a BS of a non-priority network is received at the fourth input of the control unit 16. On this signal from the first output of the control unit 16 to the second input of the receiver of the signals of the BS non-priority network 12 receives a signal for establishing communication with the BS of the non-priority network.

If the AS simultaneously communicates with the base stations of the priority and non-priority networks, from the first and second outputs of the AS 17 handover node, the fourth and fifth inputs of the control node 16 respectively receive signals for establishing communication with the BS of the priority network and establishing communication with the BS of the non-priority network. These signals from the first output of the control unit 16 to the second input of the BS signal receiver of the non-priority network 12 receives the signal of establishing communication with the BS of the non-priority network, and from the second output of the control node 16 to the second input of the signal receiver of the BS of priority network 14 receives the signal of establishing communication with the priority BS network.

If the AU is in communication with the base station of the priority network, from the first output of the transmission node AC 17 to the fourth input of the control unit 16, a signal is received to establish communication with the BS of the priority network. This signal from the second output of the control node 16 to the second input of the receiver of the signals of the BS of the priority network 14 receives a signal for establishing communication with the BS of the priority network.

The establishment of communication with a neighboring BS of both priority and non-priority networks includes synchronization with the signal of the neighboring BS and registration of the AS on this BS. After establishing the AS communication with the BS of the corresponding network, it becomes possible to transfer useful information between the AS and the BS.

If a signal of establishing communication with a neighboring BS of a corresponding network is received at a receiver of BS signals of a priority network 14 or a receiver of signals of a BS of a non-priority network 12, and the procedure for determining a neighboring BS of this network is not performed, this receiver first performs the procedure of determining a neighboring BS of the corresponding network, and then sets connection with her. In this case, the receiver of the BS signals of the non-priority network 12, according to the signal received from the antenna 10 through the splitter 11, performs the procedure of determining the neighboring BS of the non-priority network and, after detecting the BS of the non-priority network, the detection signal of the BS of the non-priority network comes from the output of the BS signal receiver of the non-priority network 12 to the first control node input 16.

The control unit 15, consisting of a control unit 16 and a handover unit AC 17, can be implemented on the basis of a single microprocessor.

From the sixth and seventh outputs of the control unit 16 to the first and second inputs of the transmitter 13 receives a signal to turn on the transmitter and the transmitted information.

After determining the BS of the non-priority network, the third input of the AC transmission device between the BS of two different cellular networks, one of which is priority over the second, (Fig. 6) receives the initial setting signal, according to which the first trigger 8 (through the first logical element OR 22) is set to the zero state, and the second trigger 9 (through the second logical element OR 23) is in the single state, so from the output of the second trigger 9 to the second output of the device receives a signal to support communication with the BS Network oh.

After determining the neighboring BS of the priority network, the second input of the AC transmission device between the BS of two different cellular networks, one of which is priority over the second, (Fig. 6) receives the BS detection signal of the priority network, and the received BS signal at the first input priority network.

In the device, the detection signal of the BS of the priority network from the second input of the device goes to the second input of the logical element And 3, and the first signal of the logical element And 3 from the first input of the device receives the signal of the BS of the priority network.

From the output of the logical element And 3, the received signal BS of the priority network is fed to the input of the signal-to-noise ratio estimator 18, which forms a sequence of estimates of the S / N ratio.

Assessment of the S / N ratio can be performed in various ways. One possible implementation method is the method and device implementing it described in US Pat. No. 6,618,232, "System and method for providing an accurate estimation of received signal interference for use in wireless communications systems". Int. Cl. ⁷ H 04 B 1/707, or as described in international application WO 02/17531 "SIR measure method and apparatus for the same".

From the first output of the signal-to-noise ratio estimation block 18, the sequence of S / N ratio estimates is supplied to the first input of the averaging block 19. In parallel with the estimates of the S / N ratio from the second output of the S / N ratio estimation block 18, clock pulses are received at the second input of the averaging block 19 records.

In the averaging block 19 in the sliding window, L values of the S / N ratio are averaged, forming K average values of the S / N ratio of the neighboring BS of the priority network.

Averaging L estimates of the S / N ratio values can be performed by averaging them in another smaller sliding window of size J (J <L). The first average value is calculated by averaging in the window the size J of the first J from L values of the S / N ratio. Then a window of size J is shifted by one of L values and the average value is calculated, etc.

From the output of the averaging unit 19, the average S / N ratios are input to the smoothing unit 20.

Smoothing the average values of the S / N ratio can be performed by various methods, for example, by digital filtering, cubic interpolation, etc. However, from the point of view of practical implementation and the amount of computational cost (for example, on a microprocessor), cubic interpolation is most preferable. Cubic interpolation is described in the book of L.I. Turchak. Fundamentals of numerical methods. Moscow, Nauka, 1987, chapter 2.

From the output of the smoothing unit 20, the smoothed average values of the S / N ratio are fed to the inputs of the prediction unit 21 and the second comparison unit with a threshold of 2.

The prediction unit 21 to the smoothed average value of the ratio S / N neighboring BSs priority network predicting the time interval T, _etc., after which the smoothed average S / N ratio to exceed a threshold input S / N ratio _Rin network.

Predict time interval T, _etc., after which the moving average value S / N exceeds the threshold input network signal / noise ratio _Rin, in various ways. For example, a sequence of equally spaced S / N ratios is predicted as described in US Pat. No. 6,426,971 B1, “System and method for accurately predicting signal to interference and noise ratio to improve communications system performance”. Int. Cl ⁷ . H 04 B 17/00) and compare them with the threshold for entering the network (S / N) _in . The time interval T, _etc., after which the moving average value of the ratio S / N exceeds the entry threshold into the network signal / noise ratio _Rin, is equal to the repetition period of the predicted values of the ratio S / N times the number of values of S / N ratio, smaller input threshold networked (S / N) _in .

The value of the predicted interval T _ave output from the prediction unit 21 is supplied to a first comparator input with a threshold 1, threshold value equal to a predetermined maximum interval T _max.

If the predicted interval T _ave is equal to or greater than a predetermined maximum interval T _poppy, then SS sequentially shifted sliding window on one of the L count ratio S / N neighboring EC priority network and on to the smoothed average values of S / N ratios at each offset predicted interval time T _CR , after which the smoothed average value S / N will exceed the threshold of entry into the network, until the predicted interval T _CR will be less than T _max .

If the predicted interval T _{pr is} less than the specified maximum interval T _pop , then from the second output of the first comparison unit with threshold 1, a signal is received at the second input of the first trigger 8 through the third logic element OR 24, setting the first trigger 8 to "single state". The second trigger 9 is set to "single state" by the initial setting signal. Thus, the signals of communication support with base stations of priority and non-priority networks respectively receive the first and second outputs of the device.

Continue on the smoothed average value of the ratio S / N neighboring BSs priority network to predict the time interval T, _etc., after which the mean value of S / N ratio exceeds the entry threshold into the network signal / noise ratio _Rin, and compare it with a threshold (maximum interval T _poppy).

If the predicted interval T _ave is equal to or greater than a predetermined maximum interval T _poppy, the first output of the first comparator with threshold 1 via the first OR gate 22 to a first input of the first flip-flop 8 receives a signal that sets the first flip-flop 8 in the "zero state". The second trigger 9 is set to "single state" by the initial setting signal. Thus, a signal to support communication with a BS of a non-priority network is supplied to the second output of the device.

The smoothed average S / N ratio of the neighboring BS of the priority network received from the output of the smoothing unit 20 to the input of the second comparison unit with threshold 2 is compared with the threshold of communication with the BS of the priority network (S / N) _ps . The threshold is equal to the specified threshold for communication with the BS of the priority signal-to-noise network _ps .

If the smoothed average S / N ratio of the neighboring BS of the priority network exceeds the threshold of communication with the BS of the priority network signal / noise _ps , then from the first output of the second comparison unit with threshold 2, a signal is received at the first input of the second trigger 9, setting the second trigger to "zero state" . The first trigger 8 was previously set to “single state”. Thus, from the output of the first trigger 8 to the first output of the device receives a signal to support communication with the BS of the priority network.

If the smoothed average S / N ratio of the signal of the neighboring BS of the priority network becomes lower than the communication threshold with the BS of the priority network signal / noise _ps , then from the second output of the second block of comparison with threshold 2, a signal is set to the second input of the second trigger through the second logic element OR 23 it is in a single state. ”Thus, from the output of the second trigger 9 to the second output of the device, signals of support for communication with base stations of priority and non-priority networks are received.

If, when turned on, the speaker will be in the cell of the priority network (the smoothed average S / N ratio of the neighboring BS of the priority network exceeds the communication threshold with the BS of the priority network signal / noise _ps ), then from the first output of the second block of comparison with threshold 2, the signal goes to the first input of the second trigger 9 and sets it to the "zero state", and through the third logical element OR 24 - to the second input of the first trigger 8 and sets it to "single state". Thus, from the output of the first trigger 8 to the first output of the device receives a signal to maintain communication with the base station of the priority network.

The averaging block 19 can be performed in various ways, for example, as shown in Fig.7.

In the averaging block 19 in the sliding window, L signal-to-noise ratio values are averaged, forming K average values of the S / N ratio of the neighboring BS of the priority network (K and J are given numbers, K> J and L = K + J).

To do this, in the first consecutive shift register 27 through the first logical element OR 25 write L values of the ratio S / N neighboring BS priority network.

Averaging L values of the S / N ratio can be performed by averaging them in another, smaller sliding window of size J.

After each write to the first sequential shift register 27 of the next value of the S / N ratio performed on the write clock pulses, from the output of this register on the read clock pulses at a frequency significantly higher than the write clock frequency, the S / N ratio values recorded in it are sequentially read that go to the first input of the second sequential shift register 28 and through the second input of the first logic element OR 25 to the first input of the first register 27. Thus, they overwrite a first register 27 and writing of the first 27 to the second register 28.

The first average value is calculated by averaging in the window the size J of the first J from L values of the S / N ratio. To do this, summarize in the adder 29 J the values of the S / N ratio, and in the divider 30 divide the resulting amount by J. The average value obtained through the first logical element AND 33 is output to the averaging block 19.

Then, when the next read clock arrives, the window of size J is shifted by one of L values and the average value is calculated, etc.

Read clock pulses are generated by the GTI clock generator 36 and are supplied to the first 27 and second 28 registers after writing to the first register 27 the next value of the S / N ratio. The number of these pulses is equal to L. For this, the second trigger 32 is set to the “single” state by the input clock pulses and set to the “zero” state by the signal received from the counter 35 after L pulses arrive at its input from the moment of the arrival of the next input clock pulse.

The first trigger 31 and the first logic element AND 33 block the output signal of the averaging block 19 until J values of the S / N ratio are written to the second register 28. For this, the first trigger 31 is set to the “zero” state by the input clock pulses, and to the “single” state by the signal coming from the counter 35, after J pulses arrive at its input from the moment of the arrival of the next input clock pulse.

The prediction block 21 can be performed in various ways, for example, as shown in Fig. 8.

The input of the prediction node 37 from the input of the prediction block 21 receives the value of S / N. At node 37, predictions predict a sequence of equally spaced S / N ratios (such as, for example, US Pat. No. 6,426,971 B1, “System and method for accurately predicting signal to interference and noise ratio to improve communications system performance”, bit. Cl ^7. H 04 B 17/00), which are output from the prediction unit 37 is input to the threshold comparison unit 38. The comparison unit 38 with the threshold being compared with a threshold input S / N ratio _Rin network. The time interval T, _etc., after which the moving average value S / N exceeds the threshold input network signal / noise ratio _Rin, is equal to the repetition period of the predicted values of the ratio S / N times the number does not exceed the threshold values. The number of S / N ratios that do not exceed the threshold is calculated by the counter 40, and the product is calculated in the multiplier 41. When the S / N ratio exceeds the threshold, the value of the predicted interval from the output of the multiplier 41 through the AND gate 39 is output to the prediction block 21.

Thus, the claimed method of handover of a subscriber station between base stations of two different cellular networks, one of which is a priority over the second, and a device for its implementation can improve the quality and reliability of communication during the transfer of service AC, which is achieved by reducing the frequency of transmission service Speakers from the original BS to the adjacent one and vice versa (decreasing the frequency of the ping-pong effect) and decreasing the probability of signal loss under fading conditions.

Claims (2)

1. A method of handing off a subscriber station between base stations of two different cellular networks, one of which is a priority over the second, in which a neighboring base station of a priority network is determined at a subscriber station served by a source base station of a non-priority network, namely, that at the subscriber station, in a sliding window, L estimates of the signal-to-noise ratio of the neighboring base station of the priority network are performed, averaged and smoothed, forming K smoothed average values sheniya signal / noise neighbor base station priority network according to the smoothed average values of the signal / noise neighbor base station priority network predicting the time interval T, _etc., after which the moving average value of the signal / noise ratio exceeds a threshold input network signal / noise ratio _Rin if predicted interval T _ave is equal to or greater than a predetermined maximum interval T _poppy, then the subscriber station sequentially shifted sliding window on one of L estimates of the signal / noise neighbor base station with priority minute and at each offset predict time interval T, _etc., after which the moving average value of the signal / noise ratio exceeds the entry threshold into the network signal / noise ratio _Rin, as long as the predicted interval T _ave is less than T _poppy, if the predicted interval T _pr less predetermined maximum interval T _poppy, then the subscriber station communicate with neighboring network priority base station and communicate simultaneously with the base stations and the non-priority the priority network, the subscriber station is compared to the smoothed with average signal-to-noise ratio of a neighboring base station of a priority network with a threshold of communication with a base station of a priority network, signal and noise _ps and continue to form K smoothed average signal-to-noise ratios of a neighboring base station of a priority network, according to K smoothed average signal-to-noise ratios of a neighboring base station priority network predicting the time interval T, _etc., after which the mean value of the signal / noise ratio exceeds the entry threshold into the network signal / noise ratio _Rin, if the prediction time interval T is _straight or olshe predetermined maximum range predictions T _poppy, then the subscriber station communicate with the base station non-priority network if the moving average signal / noise ratio neighbor base station priority network exceeds the threshold to the base station a priority network signal / noise _ps, then maintained at the subscriber station communication with the base station of the priority network, if the subscriber station communicates with the base station of the priority network, then continue to compare the average signal-to-noise ratio of the base with Antium priority network to a threshold to the base station a priority network signal / noise _ps if the average signal / noise ratio of the signal of the neighbor base station priority network is less than the threshold to the base station a priority network signal / noise _ps, then the subscriber station establish a connection with a base station neighboring non-priority networks and communicate simultaneously with base stations of priority and non-priority networks. 2. The transmission service of the subscriber station between the base stations of two different cellular networks, one of which is priority over the second, containing the first and second blocks of comparison with the threshold, a logical element And, the first and second triggers, the outputs of which are respectively the first and second device outputs, characterized in that a signal-to-noise ratio estimation unit, an averaging unit, a smoothing unit, a prediction unit, a first, second and third logical elements OR, the first input The logical element And is the first input of the device - the signal input of the base station of the priority network, the second input of the logical element And is the second input of the device - the input of the detection signal of the base station of the priority network, the output of the logical element And is connected to the input of the signal-to-noise ratio estimation unit, the first and second the outputs of which are connected respectively to the first and second inputs of the averaging unit, the output of which is connected to the input of the smoothing unit, the output of which is connected to the inputs of the prediction unit and the second of the threshold comparison unit, the output of the prediction unit is connected to the input of the first comparison unit with a threshold, the first output of which is connected to the first input of the first OR logical element, the second input of the first OR logical element, the first input of the second OR logical element and the third input of the averaging unit are combined, forming the third input of the device, which is the input of the initial installation signal, the output of the first logical element OR is connected to the first input of the first trigger, which forms the output signal supporting communication with ba call station of the priority network, the second input of which is connected to the output of the third OR gate, the first input of which is connected to the second output of the first comparison unit with a threshold, the second input of the third logical element OR and the first input of the second trigger are connected to the first output of the second comparison unit with a threshold, the second output of which is connected to the second input of the second logical element OR, the output of which is connected to the second input of the second trigger, which generates an output signal supporting communication with the base station priority network.

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