JP2007534186A - Information transmission by energy budget management - Google Patents

Abstract

The receiver-specific adjustment of the transmission power of the symbols to be transmitted can be determined in each case by applying the symbol duration, by applying the number of bits transmitted in the symbol, or by both combined measurements. It is proposed to implement using the transmitted power. As a result, each measurement provided for transmission energy adjustment implements an application of symbol duration per bit (ie, the ratio of symbol duration to the number of bits contained therein). What is important in each case, or in another form of application of the method, is to observe below the upper limit on the error recognition rate associated with the respective receiver, using the planned transmission power That is. Therefore, the transmission method according to the present invention can be called energy management (BDM) in the form of bit duration management in order to clearly distinguish the power management methods. That is, an important difference between the known method and this implies a completely new network organization called energy balance management.

Description

  The present invention relates to a method for transmitting a number of symbols each of at least one bit from a transmitter to at least one receiver using at least one channel, and a method for organizing a network. On the other hand, each having at least one bit is transmitted from a transmitter to at least one receiver using at least one channel. The invention further relates to a transmitter, a receiver and a transmission and reception system for carrying out the method.

  In general, communication engineering relates to the transmission of information from a transmitter of a communication source to a receiver that is the destination of communication. The medium used for transmission is called a channel.

  The various channels that can be used in communication engineering for the transmission of information items between a transmitter and a receiver are substantially different from each other. Wire connections are distinguished on the one hand by less interference and on the other hand by the only limited bandwidth. On the one hand, a lot of processing for interference and many echoes, and on the other hand, a relatively large bandwidth is a characteristic of a wireless connection. In addition, there are glass fiber connections associated with very high bandwidth and low levels of interference.

  For example, bandwidth, maximum transmission power, and time are defined as channel resources. Instead, for example, spectral power density or spectral energy density is limited to a particular application.

  The economic use of channel resources is required to be achieved with its joint use for as many connections as possible. In particular, in the case of a large network such as a local telephone network, in order to use as much as possible with an effective channel capacity, a fixed part of the effective channel capacity is used for each subscriber in the contents of the line switching connection It was not proven whether it should be appropriate to assign to. In known transmission methods, channel capacity is allocated to individual subscribers using various multiplexing procedures, such as in a run, WLAN, GSM network, UMTS network, telephone network, and the like.

  All multiplex methods involve partitioning into effective channel capacity. In TDMA (Time Division Multiple Access) and FDMA (Frequency Division Multiple Access) methods, as long as the time zone or frequency band assigned to different users is set up, the division is performed at the physical level. In addition, there are CDMA (Code Division Multiple Access) systems that perform the division by coding as long as various orthogonal codes in a specific implementation are associated with each user, and each code is received at the receiving terminal. Once known, messages intended for one receiver can be separated from messages for other receivers.

  Network planning and development is performed taking into account the characteristics of various channels. Cell size optimization, for example in GSM networks, depends on the geographical location and hence the existing subscriber density and multipath conditions. In that respect, the planning process is linked to what is considered the worst. In other words, the maximum distance or the minimum received power (sensitivity) in the network is determined in advance. Since the network is so sized, all subscribers can receive the same symbol rate.

  It ensures that even those receivers where the lowest level of transmission quality still applies can provide a minimum level of transmission quality. The transmission quality can be quantified based on, for example, an error recognition rate at the receiver, eg, a bit error rate (BER) base. In the context of this application, the different types of error rates well known to those skilled in the art are grouped together by a generic term for error recognition rates.

  The state of the art in the field of channel management will now be described with reference to some examples.

a) WLAN standard 802.11 b
According to the standard for local transmission networks (wireless local area networks, WLAN) for data transmission in the ISM band 2.45 GHz
• CDMA sequences are used to be strong with respect to multipath propagation.
A RAKE receiver is optionally used to provide optimal focusing of individual multipath energy.
Error correction codes are used to decipher the correct information despite individual errors in the data stream.
Different modulation modes (BPSK, QPSK, CCK) are used to convey the maximum data rate or the data rate on demand, depending on the reception characteristics of the channel.

  As a result, for each peer-to-peer connection in the network, depending on the quality of each of the available transmission channels, the data signal can be set up fluidly in the network. It is possible to apply it to the element which concerns speed.

  With regard to the characteristics of the transmission channel, the result is to transmit a maximum data rate of 11 Mbps, or use an additional convolution code to reduce to 5.5 Mbps, or even higher channels for worse channels Can avoid CCK modulation and transmit with QPSK only or BPSK only, which reduces the data rate to the symbol rate used during transmission (1MSps), and only 1Mbps is still possible . In that regard, various modulation modes are used while retaining the original evolution of the data symbol. Subscribers who suffer from excessive attenuation due to excessive distance can no longer be reached. In addition, the channel capacity cannot be set for optimal use in this way.

b) UMTS
This mobile radio standard (universal mobile communication service) has the same characteristics as the standard 802.11b. Within the mobile radio area, many subscribers have means to access the base station. For this purpose, a CDMA (Code Division Multiple Access) method is used and each subscriber has a fixed code that is fluidly assigned. Furthermore, the base station antennas are arranged to be generated in different sectors and have only a slight influence on each other (space diversity).

  UMTS has power management that tries to keep the power of all subscribers received at the base station equal. This is particularly important in terms of CDMA channel separation. At the same time, the effort is to match all the subscribers in the network to the lowest possible level of transmit power.

  The use of long CDMA sequences and rake receivers allows the system some robustness associated with strong multipath propagation. Nevertheless, individual cell sizes are greatly limited compared to GSM systems. The bandwidth used is relatively large due to the expansion method employed. Nevertheless, each subscriber has only a relatively greatly reduced data rate due to the adopted CDMA sequence representing the data symbols.

  The enlargement is performed by a procedure, whereby a short physical symbol is determined in relation to a predetermined bandwidth, which is referred to as a chip. A transmitted symbol carrying information or a subscriber's specific CDMA sequence spans many chips.

  The system so configured is robust and ensures a minimum transmission quality maintenance for each subscriber of the cell. The fact that this is no longer sufficient for modern networks, however, was something developers were aware of here, as fluid deployment options were additionally adopted.

  A feature of the UMTS system is that it allows channel bundling. In that case, many logical channels are assigned to individual users. A shortened sequence is used here so that the user does not receive many CDMA sequences in parallel. In this way, the data rate is increased. In that way, a higher data rate can be provided to a person called a power user in return for the corresponding fee.

  On the other hand, the robustness of data transmission also decreases with the increased data rate. Thus, the increased data rate is only available for channels with good quality (ie low noise power). Moreover, it is only possible to use a specific channel for bundling, which must include all new simplified codes, thus increasing the level of interference associated with other users and managing complexity. The costs and costs will rise significantly. However, a critical aspect is that the channel resources here are not optimally used.

  Germany, 199 37 706 A1, discloses a transmission method with frequency and time expansion at the transmitting end. In this transmission method, which is also called multidimensional multiple access method (MDMA), information symbols to be conveyed are subjected to frequency expansion and time expansion at the transmitter terminal. Furthermore, different transmission powers can be assigned to individual subscribers. The received signal is not expanded at the receiving terminal. Each expansion effect and resulting system gain can be compared to the required transmission quality and current channel characteristics. With a reference pulse that helps to verify the channel characteristics, a time extension range can be implemented when making a connection between the base station and the subscriber station. MDMA makes it possible to adapt to every requirement in the network and each subscriber, and the quality that demands it. Thus, MDMA represents a machine that can be used technically to give each subscriber an optimal supply.

However, it is not enough in itself. The questions that arise are:
How should the network be managed to be able to provide the user with valuable benefits such as data rate, range, error protection, robustness, etc. in an optimal way? In other words, how to operate the machine in an organized way to translate the flexibility of MDMA into an economic advantage.

  Accordingly, it is an object of the present invention to provide a method for transmitting at least one symbol from a transmitter to at least one receiver, the method comprising a transmission state between the transmitter and each receiver. To provide the highest possible data rate. As a further aspect of the technical objective of the present invention, what follows is to provide a method of network organization that provides the data signal rate to any subscriber in the network, the method comprising: And as much as possible depending on the transmission status between the receiver and the individual receivers, and in this regard, better use of available channel resources.

According to a first aspect of the invention, there is proposed a method for transmitting a number of symbols each having at least one bit from a transmitter to at least one receiver with at least one channel and a predetermined transmission power. ,
Symbols are transmitted and received so that the receiver-specific transmission energy is symbol reception at the receiver side, and the received energy corresponds to the upper limit value associated with the receiver or a lower error recognition rate. In order to achieve the highest possible bit rate, depending on the current dominant transmission conditions between the transmitter and the receiver at the same time, the symbol duration, per symbol of transmitted bits Or the symbol duration and the number of transmitted bits per symbol.

According to a second aspect of the invention,
Provided in a method for organizing a network for transmitting symbols using at least one channel and a predetermined transmission power for each transmission of a number of symbols having at least one bit from a transmitter to at least one receiver;
The receiver-specific transmission energy is symbol reception on the receiver side, and the reception energy corresponds to the upper limit value related to the receiver or the value of the generated error recognition rate that is lower than the upper limit value. Depending on the current transmission state between the transmitter and the individual receivers, the symbol duration, the symbols are transmitted, the receiver specific transmission energy, and at the same time to achieve the highest possible bit rate Or the number of transmitted bits per symbol, or the number of symbol durations and transmitted bits per symbol.

  The two proposed methods are based on the same invention. The method according to the first aspect of the invention will hereinafter be described as technical rules for data transmission between a transmitter and at least one receiver as a transmission method according to the invention. The use of technical rules in the network for each transmission of a number of symbols between a transmitter and at least one receiver is based on the network based on the method described in the second aspect of the invention Form technical rules for organizing The latter method is hereinafter referred to as a network organization method based on the present invention.

  Also, the use of the transmission method of the present invention can be achieved without using the network organization method according to the present invention unless the transmission method according to the present invention is used for each transmission.

  It will be appreciated that the use of the network organization method according to the invention anticipates the use of the transmission method. The network organization method is also related to any data transmission in the network. The use of network organization methods allows maximum in terms of increased efficiency, as will be described in detail below.

  Some terms used below are described in more detail for a better understanding of the present invention.

  The term symbol in accordance with the present invention is used to indicate a signal that represents a logical symbol unless stated otherwise. A logical symbol includes one or more bits.

The transmission of symbols with receiver-specific transmission energy basically means that the transmission energy is determined individually for each individual receiver. According to the present invention, transmission energy determination occurs at the receiver side, and symbol reception occurs at a received energy corresponding to an upper limit associated with the receiver or a lower value for error recognition rate.

This does not eliminate the same transmission energy determined for many groups of receivers if the same current transmission state applies to groups of receivers that are approximately the same distance from the transmitter.

  The term scheduled transmission power is used as a distinction from known power management methods to indicate a transmission power that is maintained on a time average rather than being variable in the content of the method according to the invention. In addition or alternatively, an upper limit in terms of peak power is predetermined, which is maintained in the context of the method according to the invention. However, it is also possible to change the transmission power preset from the outside, so that the method according to the invention can be applied by applying the symbol duration, the number of bits per symbol, or by applying both parameters. Therefore, it works. Various implementations for transmit power presets are described below.

  The current transmission state is defined by all parameters that affect the error recognition rate of the current receiving terminal. The effect on the transmission state is not only the modulation mode used and the duration of the symbol, but also, for example, the distance between the transmitter and the receiver (distance attenuation), multipath attenuation and the interference arising from it at the receiver. Formed by influences, eg interference interference from nearby transmitters and noise, jado effects due to interference in a single path, channel interference effects and system interference effects.

  The upper limit of the used error recognition rate is, for example, the bit error rate value (BER), the frame error rate (FER), or the block error rate (BER), or any equivalent that affects the error recognition rate. Any value may be used.

  The relationship between the limit value of the error recognition rate and the receiver is, for example, the data transmission between the user of the receiver or the transmitter and the receiver (phone conversation, mail, multimedia data transmission, security use, etc. The maximum error recognition rate guaranteed to be compatible with the service type linked to the transmission of context data).

  While maintaining the maximum error recognition rate associated with the receiver, when using the planned transmit power and receiver specific transmit energy per symbol, the indication of the highest possible data rate is the highest possible. Used to indicate whether the data rate is This means that the data rate can be different for each receiver, contrary to the traditional method. This will be described in detail below with reference to the drawings.

The solution according to the invention is first considered in more detail below, before describing the examples.

  The transmission method of the present invention is separated from the known power adjustment method (power management). In particular, for example, known GSM or CDMA methods control the power of the transmitter. This is not economically efficient for network operators. The adjustment of transmit power related to power management means that the channel capabilities available to network operators cannot be set for optimal use. In addition, the present invention is based on consistent replacement of implementations, in which the received energy per bit rather than the received power is determined in order to achieve an upper limit in terms of error recognition rate on the receiver side.

  According to the invention, therefore, receiver-specific adjustment of the transmission energy of the symbol is achieved by applying a symbol duration or by applying the bit transmitted in the symbol, or using a predetermined transmission power respectively. In some cases, it is carried out by the combined method of both. As a result, each measurement provided for transmit energy adjustment applies an application of symbol time per bit (ie, the ratio of symbol duration to the number of bits contained therein). What is important for the application in each case when achieving the highest possible data rate and at the same time using a given transmit power, or in another form of this method, is in each receiver Observe or fall below the upper bound on the associated error recognition rate. The transmission method according to the invention can also be referred to as energy management in the form of bit duration management (BDM) in order to clearly show the distinction from the power management method. That is, an important difference between the well-known method and this is to mean and enable a completely new network organization.

  Based on bit duration management, the network organization method according to the present invention allows more efficient use of effective channel capacity for network operators. In a network, the goal is to provide many subscribers with a given amount of information in a given period. With scheduled transmit power, a given duration requires a total available energy balance for all subscribers. The network organization method according to the present invention optimizes each channel in a receiver-specific manner. More specifically, the energy required to achieve the expected error recognition rate and data transmission as fast as possible (i.e. the highest possible data rate) were intended for subscribers. Assigned to each symbol. This allows a greater amount of information to be communicated or supplied to more subscribers compared to known network organization methods.

  This is not achieved successfully by adjusting the transmit power, as a decrease in transmit power below the transmit power reset value in the context of power management does not use the resources related to transmit power completely. Only when preset transmission power is observed, full utilization is successfully achieved.

  As a result, the network organization method according to the present invention uses the parameters available to the network operator in an improved way as energy balance, i.e. transmission power and time. Therefore, the network organization method of the present invention is hereinafter referred to as energy balance management (EBM).

  One embodiment of the method according to the invention is described in more detail below. Since the transmission method forms a basic cell of the network organization method, the embodiment described below as an example also relates to the transmission method and the network organization method of the present invention.

  Each of the three measurements proposed to apply measurement energy that causes a change in symbol duration per bit corresponds to an independent transmission method according to the present invention. Alternative application combinations are advantageous but not required.

  The second embodiment of the transmission method according to the invention is therefore simply whether the symbol duration is applied. The second embodiment simply provides that the number of bits per symbol applies. The third embodiment provides that the number of bits per symbol and the symbol duration are applied simultaneously.

  Another embodiment according to an example of a transmission method according to the invention provides a selection step in which a selection is made between two or three of the applications described above. The fourth embodiment selectively uses either the application of symbol duration or simply the application of the number of bits per symbol. The fifth embodiment optionally uses only application per symbol or application of symbol duration and simultaneously the number of bits per symbol. The sixth embodiment optionally uses only the application of the number of bits per symbol or the application of the symbol duration and the number of bits per symbol at the same time. The seventh embodiment optionally uses only the application of symbol duration per symbol, or the application of the number of bits per symbol, the application of bit duration and simultaneously the number of bits.

  Desirably, further embodiments can be implemented with many or all of the above-described embodiments.

  In the following, some implementations regarding transmit power presets are discussed.

  In one embodiment of the present invention, transmit power and / or field strength and / or spectral power density are maximized in a channel-specific manner on a time average and within the limits of allowable power radiation. Allowable transmit power and / or electric field strength and / or magnetic field strength and / or spectral power density are predetermined by the supervisory authority. In the case of the network organization method according to the invention, energy balance management, maximum utilization of the available energy balance is thus achieved. Time averages relate to those time segments whose reciprocal is significantly less than the bandwidth.

  In a further implementation of time averaging, the transmit power is at maximum within the limits of the transmitter's technical design. The maximum of the technically possible use of the energy balance available to the transmitter is thus achieved if it stays below the allowable power.

  In a further embodiment, the transmission power can be preset. Changing the transmit power in advance represents an external intervention in the method procedure of the present invention. For example, the option to pre-set the transmit power can be provided to the mobile terminal user in the context of this embodiment. Thus, for example, in an environment that is susceptible to interference, the user can adjust the transmit power according to his desires to keep the radiation of the device as low as possible. Then, to achieve transmit energy, when the transmission conditions remain the same and the decrease in transmit power preset causes a decrease in the maximum data rate that can be achieved with the transmission procedure, the symbol is either a larger symbol duration or Sent in a correspondingly smaller number or both.

  Described below is an embodiment relating to the operation of ascertaining the required transmission energy.

  In another embodiment, a step is provided for ascertaining the currently prevailing value of received energy with a given transmitted energy. For example, RSSI measurement (radio signal strength indicator) for received power can be performed at the receiver side, and a signal depending on the measurement result can be transferred to the transmitter.

  Alternatively or additionally, a step can be provided for ascertaining the currently prevailing value of the error recognition rate at the transmitter or receiver. In that case, the error rate can be ascertained by determining the number of errors in the received data frame. Alternatively, the error recognition rate can be ascertained by averaging the number of errors in many data frames. Moreover, the error recognition rate can be ascertained by the number of negative received signals at the receiver during the scheduled period. The error recognition rate is, for example, a bit error rate (BER), a block error rate (BLER), or a frame error rate (FER). Frequently used redundant coding and iteration strategies are included there.

  In another embodiment, the application of the symbol duration is performed depending on the currently prevailing value of the error recognition rate at the receiving terminal or depending on the current noise power density value at the receiving terminal.

  In another embodiment, the receiver communicates the current error recognition rate or current value of noise power density to the transmitter. Further, alternatively or additionally, the transmitter estimates the current error recognition rate or the current noise power density value at the receiving terminal.

  In a further embodiment, in an existing connection or ongoing data exchange, depending on the current transmission state between the transmitter and the receiver, the symbol duration and / or the number of bits contained in the symbol may be Traffic is readjusted fluidly without being blocked. In other words, no symbol duration setting is performed not only when forming a connection, but more particularly during an existing connection, and more specifically, preferably specifically for the receiver. The change in symbol duration is performed during connection, during time continuity, another similar continuity, or during a connection at a predetermined time interval.

  In a preferred embodiment, the symbol duration is applied individually in a channel specific manner, ie on each channel used. In particular, it is possible to do so to receivers where symbols are transmitted on multiple channels, which symbols are applied individually in terms of their duration on each channel according to their transmission conditions. The

  In an embodiment, the symbol duration is limited in a channel specific manner to a short symbol duration value only by the channel bandwidth. It provides a particularly wide range of values for changing the symbol duration. The symbol duration can be determined from the continuous spectral value, or alternatively from the discrete spectral value, in which the discrete spectral value is the shortest possible symbol in a channel-specific manner. Includes an integer multiple of the duration.

ここで、E_minは、受信機に関係する誤り認識率の上限値に対応する受信エネルギー、P_sendは最大送信パワー、r₀は基準の距離、αは伝播係数である。 In a preferred embodiment, the symbol duration T _simble is determined at the transmitting terminal according to the following formula:

Here, E _min is the reception energy corresponding to the upper limit value of the error recognition rate related to the receiver, P _send is the maximum transmission power, r ₀ is the reference distance, and α is the propagation coefficient.

  Described below are implementations relating to the application of the number of transmitted bits per symbol or the selection of the symbol type.

  In another embodiment of the invention, the selection of the number of transmitted bits per symbol is performed according to the current value of the error recognition rate at the receiving terminal or the current value of the receiving terminal of the noise power density.

  Preferably, the number of transmitted bits per symbol is adapted in a channel specific manner. It can mean that the receiver receives different symbol types on different channels during connection. As such, the data rate on each channel can be optimized individually.

  In another embodiment, further implementation of the number of transmitted bits per symbol is implemented when a very short symbol duration is already used in channel specific terms. It helps control the communication between the transmitter and the receiver in order to transmit the symbol type to be used as long as possible.

  In a further embodiment, the symbol type with the largest possible number of bits is selected for transmission, which does not exceed the upper limit of the error recognition rate at the receiving terminal.

  Embodiments for various transmission alternatives are described below.

  In a further embodiment, the symbols are each transmitted in a state of being divided into a sequence of chips. In that case, as long as the symbol is modulated with a noise sequence (real noise) or a pseudo-noise sequence, the symbol can be expanded in terms of frequency. Desirably, the noise or pseudo-noise sequence is fluidly adapted to the selected symbol duration. This can be done, for example, by a procedure in which the first chip is always removed from a long m-sequence, so that a symbol duration is provided in total.

  Instead, it is possible to use CDMA sequences instead of pseudo-noise sequences, so that many connections can be formed in a parallel relationship.

  When symbols are transmitted in such a way that the available channel bandwidth is fully used, maximum utilization of available channel resources is achieved in relation to the frequency axis. Preferably, therefore, the symbols are transmitted on condition that the frequency is expanded.

  A chirp signal indicates that a long symbol does not necessarily mean a small bandwidth. Thus, in a particularly preferred embodiment, the symbols are transmitted in the form of a chirp signal. In that case, a long symbol can be replaced with a chirp signal that is of the same duration. In that case, the product of time duration and transmission power is the same for both pulse forms, i.e. the energy is the same. However, the chirp signal spreads linearly in the simplest case, but in general it can be assumed that the function form desirably rises monotonically or falls monotonically, and the total planned bandwidth Represents a frequency modulation that can span As such, the signal is expanded in frequency.

  In a further embodiment, transmitter chirp signals (which are intended for each receiver) can overlap each other in time. In that case, the sum of the magnitudes of power emitted at some instant and superimposed on each other's chirp signal is equal to the maximum allowable transmit power on the band.

  The above signal expansion effects provide very severe multipath propagation and / or expansion gain useful for channels that suffer from additional interference signals. In that case, the quality of the received signal is highly dependent on the selected expansion of the signal. Since the maximum bandwidth can always be used, energy balance management is directly accompanied by that value. Therefore, as the duration of the pulse increases, the expansion and the symbol energy at the same time increase.

  If an appropriately correlated receiver is used, for example, if there is a matched filter suitable for the receiver and it is applied fluidly, the energy contained in the expanded symbol will be used for optimal use. be able to.

  Alternatively, in the case of long symbols, it is also possible to overlap the FDMA method, so that the available bandwidth is divided and the addressed user has a small portion of the bandwidth (which is the respective data (Corresponding to the signal length) only. It is possible for two or more FDMA channels to be operated in parallel.

  In that respect, the transmitter dynamics have significant significance when splitting into FDMA channels, and at the same time, in the case of the above mentioned poor channel conditions, a smaller bandwidth is allocated, and hence at the same time smaller Allocate bandwidth to the case discussed above under insufficient channel conditions, and hence the optimal symbol is longer and the better channel is allocated to parallel shorter symbols, resulting in higher bandwidth Assign.

  Here it is found that the energy balance management according to the invention can actually be linked to any modulation mode and any access method.

  In a further embodiment, a multiplexing method (preferably a TDMA method) is used on the channel as soon as the transmission load of the channel allows. As such, it is possible to ensure better utilization of channel capacity for channels that are associated with the receiver in good transmission conditions, so that items of information to be transmitted are transmitted in only a short time. obtain. In that situation, the optimal symbol energy is determined by the error recognition rate for the various possible modulation modes and by the selected modulation mode (which ensures the required transmission quality in this modulation mode). The At the same time, it provides a choice of higher stage modulation that can send data as quickly as possible, so that the associated channel capacity is set for optimal use. In that situation, the symbol duration is not changed because the symbol duration has been reduced to a minimum corresponding to the inverse of the bandwidth.

  In a preferred embodiment, the transmitter is the user's mobile terminal, and prior to the transmission of symbols to the base base station, the transmitter receives information from the base base station on the frequency band to be used for transmission. Receive.

  In a further embodiment, the base station checks the incoming signal of the mobile terminal in a number of modulation modes and uses the modulation mode recognized as correct in receiving the mobile terminal's signal. For example, the base station receives signals by many receivers, the modulation mode is associated with each receiver, and the mobile terminal is available at the end of the transmitter for the transmission of symbols to the base station Use one of the different modulation modes.

  According to another aspect, a transmitter is provided for performing the method according to the invention.

  A transmitter for carrying out the method produces a signal representing a logical symbol (hereinafter referred to as symbol) and has a transmission unit adapted to emit it, the logical symbol being one bit Or multiple bits. In addition, the transmitter has a controller adapted to generate and transmit control signals based on items of information that exist regarding the currently prevailing transmission state between the symbol transmitter and receiver, The transmitter unit processes the receiver-specific transmit energy corresponding to the upper limit of the error recognition rate associated with the receiver or a value lower than the limit value of the error recognition rate and is appropriately adapted. The number of symbols in symbol duration or in a suitably adapted number per symbol of transmitted bits or in a suitably adapted number of symbols duration and appropriately adapted per symbol of transmitted bits In order to generate and supply a control signal to process the use for transmission to the unit, the control unit can transmit and receive the transmitter specific transmission energy at the same time. Depending on the current conditions of transmission between, for the purpose of achieving the highest possible bit rate is further adapted.

  An embodiment of a transmitter according to the invention is described in detail in claims 46-77. The advantages of the transmitter according to the invention and its embodiments are directly and clearly derived from the method aspects of the invention and the different embodiments of the method according to the invention.

  In certain preferred embodiments according to an example of a transmitter according to the invention, the signal that can be emitted can be stored in a memory or read from a shift register structure.

  In an alternative or addition in certain preferred embodiments, the transmitter unit of the transmitter is adapted to produce any signal to be radiated in the execution of one or more algorithms, the algorithm comprising a suitable circuit Or in the form of software. The transmitting unit currently generates each signal to be emitted by a control signal from the controller. As such, for example, any signal such as a chirp signal or a BPSK signal sequence can be generated.

  Preferably the transmission unit has a signal sequencer and an IQ modulation unit connected to its output. The signal to be radiated is passed to the signal sequencer and IQ modulation unit after its generation, and then converted directly into the carrier band.

  A further preferred embodiment of the transmitter according to the invention has a programmable transmitter structure (software radio). Desirably, the transmitter structure, particularly the mode of operation of the transmitter, is fluidly variable. Such a large number of transmission symbols can be created.

  A further embodiment of the transmitter according to the invention has a channel estimation unit in order to determine the characteristics of the channel as accurately as possible.

  According to a further aspect of the invention, there is provided a receiver for performing the method according to the invention. The features of the receiver according to the invention and its preferred embodiments are directly and clearly derived from the description of the method aspects and embodiments therein.

  Preferably, the receiver has a programmable receiver structure (software radio). The receiver structure and in particular the mode of operation of the receiver is fluidly variable in the embodiment.

  According to a further aspect, a transmission and reception system is provided for performing the method according to the invention. Features of the construction of the transmitter / receiver according to the invention and various embodiments are set forth in claims 78-82. Their advantages are directly and clearly derived from the following description of the method aspect and transmitter according to the invention and the receiver according to the invention.

  The invention is explained in more detail below with reference to exemplary embodiments and figures.

  FIG. 3 is a diagram illustrating the relationship between the magnitude of the energy density ED, the transmission frequency f, and the time t in a three-dimensional manner. Time t is plotted on the horizontal axis (x-axis) on this paper, while energy density ED is plotted on the vertical axis (y-axis) on this paper. The transmission frequency f is plotted on an axis (z axis) extending in a predetermined direction with respect to the paper surface.

Under the time axis, the duration of the data frame is represented by the length of the double-headed arrow specified by T _FRAME between two instants at times t ₁ and t ₃ . The symbols 13 to 16 are represented along the time axis as part of the cube EB. Symbols 13-16 have different symbol durations T _symbol . In symbol 13, the symbol duration T _symbol is illustrated by a double-headed arrow between the instants of times t ₁ and t ₂ .

The bandwidth B available in the channel between the _two limit frequencies f ₁ and f ₂ is specified by the length of the double-headed arrow placed parallel to the z-axis.

は、周波数fで最大で送信される。その値は、シンボル１３に対しては図１中に、長方形１０の領域内容として示される。その長方形１０は、シンボル１３の期間T_symbolと、0からED_maxまでのエネルギー範囲により決定される(ED、t)面に拡がる。シンボル１３のためにED_maxを通して頻度に従ってシンボル１３の期間T_symbolと0からのエネルギーの長さの上断固とした(ED、t)飛行機で広がる長方形１０の領域内容として値を図１における表現に提供します。したがって、３次元的な表示は、スペクトラルエネルギー密度の古典的な定義を含む。 Spectral energy density during symbol duration T _symbol :

Is transmitted at a maximum at frequency f. The value is shown for the symbol 13 in FIG. The rectangle 10 extends on the (ED, t) plane determined by the period T _{symbol of the} symbol 13 and the energy range from 0 to ED _max . For symbol 13 the value in the representation in FIG. 1 as the content of the area of the rectangle 10 spread on the plane (ED, t) of the length of the symbol 13 period T _symbol and the energy from 0 according to the frequency through ED _max Offers. Thus, the three-dimensional representation includes a classic definition of spectral energy density.

  The power P that can be radiated at the transmitter instantly in time corresponds to the instant of time t given in FIG. 1 of the (ED, f) plane 12 of the cube EB. Thus, the three-dimensional display includes a classic definition of current power.

  The illustrated energy density can be determined by, for example, the Wigner-Ville transformation.

  The spectral energy density at a given frequency f is limited by the upper limit of the value ESD in consideration of, for example, the law. Similarly, the average or maximum transmit power is limited in view of statutory provisions or in consideration of transmitter technical options that limit the transmit power to a maximum value. The possible energy density based on such a restriction is symbolized by the length of a double-headed arrow placed parallel to the Y axis.

Due to the frequency bandwidth B of the transmission channel between the lower frequency f ₁ and the upper frequency f ₂ shown in FIG. 1, there is a cube EB whose range along the frequency axis is equal to the bandwidth B of the transmission channel To do.

The cube EB characterizes the limited energy balance of the transmitter, which energy balance is available to the transmitter for the bandwidth B channel of period T _FRAME .

により、si関数と長方形関数に従う。 This relationship is also based on the relationship between bandwidth and symbol duration. It is known that the maximum bandwidth is fully utilized by short symbols. In particular, and for example, in a rectangular spectrum, the bandwidth is completely filled by the si-function. It is a Fourier transform:

According to the si function and the rectangle function.

ここで、パルス持続時間Tは、相互のシンボルの干渉現象なしで、可能な２つのシンボル間の最小の距離を示す。 Thus, baseband has the following simple relationship between pulse duration and critical frequency:

Here, the pulse duration T indicates the minimum distance between two possible symbols without the mutual symbol interference phenomenon.

  Since generally the carrier frequency is additionally used for transmission, the transmitted bandwidth B corresponds to twice the magnitude of the critical frequency fg in baseband (B = 2fg).

The cube parts 13-16 shown in FIG. 1 symbolize the components of the energy balance used for transmission of the respective symbols by the transmitter during the frame duration T _FRAME . It can be seen that the symbol duration of the second symbol 14 is less than that of the first symbol 13. In a corresponding manner, the transmission energy of the second symbol 14 is less than that of the first symbol 13.

The following results can be obtained from the model of FIG.
a) Channel resources available to the network operator are, for example, bandwidth, maximum transmit power and time. The cube EB of FIG. 1 corresponds to the energy balance available to the operator of the transmitter at all frequencies of the channel used by the transmitter during the frame. However, it does not mean that the frame duration T _FRAME is fixed. It can also be changed by energy balance management.
b) The economical operation of the transmitter requires full utilization of the available energy balance. Maximum transmit power and available bandwidth should always be used throughout the entire period of transmission operation to make optimal use of available resources.
c) Flexible adaptation to the variable transmission status between the transmitter and its associated active receiver is realized by the energy balance management available at the transmitter within the period. An essential physical parameter for successful information transmission from the transmitter to the receiver is not a transmit power, but a sufficiently high amount of bit-related received energy. A basic feature of the method according to the invention is the bit duration management at the scheduled transmission power in the form of a receiver specific adaptation of the bit related transmission energy due to the change of the bit related duration of the symbol. is there. In the following, those findings will be discussed in more detail.

により、理論的に最適に使用することができる。式中のBは、チャンネルの帯域幅を示し、S/Nは、受信端末での信号パワーとノイズパワーとの間の比を示す。ノイズパワーは、受信端末での熱ノイズと、人間または産業上の影響(人間が作ったノイズや産業上のノイズ)のため起こる干渉現象との合計である。パラメータCは、チャネル容量として特定される。経済的なチャンネル管理のための基本な特性は、上記のShannon公式である数式７から読みだすことができる。送信機と受信機の間の送信チャンネルの容量は、受信信号のパワーSに対する受信機で行き渡っている雑音パワーNの比率(S/Nと称する)に本質的に依存する。したがって、チャネル容量は、セルかローカルネットワークに対して一定の固定された値ではなく、一つの受信機から他への、および時間の経過による送信チャンネルのそれぞれの品質に依存して大きな変化を受ける流動的な値である。 a) Channel capacity and energy balance
According to Shannon, the available transmission channels with the amount of data are described in hits per second and the amount of data transmitted in an error-free manner per unit time:

Therefore, it can be used theoretically optimally. B in the equation indicates the channel bandwidth, and S / N indicates the ratio between the signal power and the noise power at the receiving terminal. The noise power is the sum of the thermal noise at the receiving terminal and the interference phenomenon that occurs due to human or industrial influences (noise made by humans or industrial noise). Parameter C is specified as channel capacity. The basic characteristics for economical channel management can be read from Equation 7, which is the Shannon formula above. The capacity of the transmission channel between the transmitter and the receiver essentially depends on the ratio of the noise power N spread at the receiver to the power S of the received signal (referred to as S / N). Therefore, the channel capacity is not a constant fixed value for the cell or local network, but is subject to large changes depending on the quality of each transmission channel from one receiver to another and over time It is a fluid value.

b) Regarding channel capacity utilization As stated in Equation 7, the channel capacity according to Shannon is always limited by the planned limits in the transmission channel. In other words, the channel capacity at a given moment in time is a limited resource, and the network operator establishes a communication network (which may be a wired communication network or a wireless communication network) It is the actual economic profit that you get by. The capital investment required for that purpose requires an optimal utilization of the channel capacity provided in order to be able to operate it economically. Full utilization of the available capacity of the transmission channel is possible only when the planned transmission power (preferably the maximum allowable transmission power) is radiated on the channel.

c) Regarding energy balance management The above formula from Shannon specifies the maximum data rate that can be transmitted without error. In practice, a transmission error occurs. In this regard, bit error rate (BER) is a basic parameter in telecommunications. Transmission errors must be corrected by appropriate measurements. This is implemented, for example, by incorporating redundancy into the data stream at the transmitting terminal to be transmitted. As such, errors can be recognized. The bit error rate is highly dependent on the modulation selected. In general terms, it is possible to derive the relationship between the bit error rate and the ratio of the transmitted symbol energy Es to the noise power density No in all modulation modes. Therefore, for successful transmission of information, it is essential that the transmitter recognizes symbols by giving the receiver the minimum energy related to the noise power density per symbol or per bit. The minimum energy required depends on the current noise power density and the BER associated with the receiver and also provided, for example, based on contractually agreed transmission quality. Moreover, the minimum energy required depends on the distance between the transmitter and the receiver. In order to clearly illustrate the results derived from the model shown in FIG. 1 in accordance with the present invention, three example cases are described below.

a) Low attenuation First of all, consider the preferred case when the attenuation between the transmitter and receiver is relatively low. In that case, the corresponding user can utilize a very large channel capacity. In order to assume that the transmission energy per symbol is the minimum and at the same time the maximum transmission power, the shortest possible symbol that can be implemented in relation to the current band is always transmitted. Optionally, a higher stage modulation corresponding to the reception quality is additionally applied so that the maximum available energy at the receiver can be used.

  In such a case, the optimum symbol energy is determined by the modulation mode, for example, by the BER considered for the various modulation modes, and the required transmission quality is selected and guaranteed. At the same time, it provides a choice of higher stage modulation that can transmit data as quickly as possible so that the channel capacity involved is in optimal use. In that case, since the duration of the symbol has already been reduced to a minimum corresponding to the inverse of the bandwidth, the duration of that symbol is no longer changed. Its high channel capacity equipment means that the amount of data needed can be transmitted quickly, so that by using an appropriate multiplexing method, one or more users can utilize the physical channel. . For example, since the TDMA method is advantageous for the connection, the associated management complexity and cost are kept within limits.

b) High Attenuation Another case scenario here involves physical transmission channels that involve users with very high attenuation due to long distances or fading effects that occur due to multipath propagation phenomena. . In that case, the channel capacity available at the receiver is very small, and the transmitted symbol energy must be very large, ie very long symbols are emitted.

  In that situation, the optimum symbol energy is determined by consideration given to only the simplest available modulation. In order to dynamically change the symbol duration at the transmitter and always generate subscriber-related symbol energy at the receiver, the minimum energy to be received in the modulation (for example, the required BER is Maintained) is preset permanently.

  In this situation, the symbol is significantly longer than the shortest symbol duration predetermined by the bandwidth. Optimal use of channel capacity should therefore be reconsidered under more specific conditions related to channel bandwidth besides S / N [W / W].

  If the symbol bandwidth used is less than or equal to the planned bandwidth, the maximum channel capacity cannot be used and further additional measures must be taken. Such measures are described below.

  Long symbols do not necessarily mean a small bandwidth, which is indicated by a chirp signal as shown in Germany 199 37 706. In that case, a long symbol can be replaced with a chirp signal that is of the same duration. For both pulse forms, then the product of time duration and transmit power is equal to both pulse forms, ie the energy is the same. However, the chirp signal may be assumed to have a frequency modulation that can span the entire planned bandwidth (in the simplest case, it will spread linearly, but in general it will be somewhat monotonically rising). Can). As such, the signal is expanded in terms of frequency. The situation is discussed in more detail below.

  It is also possible to expand the symbol in terms of frequency by further adjusting the symbol with a pseudo-noise sequence. It will be appreciated that the modulation needs to be known to the receiver and must be fluidly adapted to the selected symbol duration.

  A particular variation of energy balance management provides for predetermining the duration of a chip that reflects a given band for long pseudo-noise sequences, eg m-sequences. With maximum bandwidth, the various symbol durations can then be performed in discrete steps (integer multiples of the chip) by always using portions of the scheduled sequence.

  For example, if a receiver that must be fluidly matched has an appropriate matched filter, then the energy contained in the expanded symbol will only be used optimally when an appropriately correlated receiver is used. be able to.

  Instead, for long symbols, the bandwidth involved is split, and FDMA can be overlaid because the users involved are only allocated to a small portion of the bandwidth (corresponding to the length of each data symbol) It is. Two or more FDMA channels can be operated in parallel.

  Particular embodiments can be provided for uplink and downlink channel implementations in the form of frequency division duplex (FDD), which operates in time.

  In that regard, the transmitter dynamics discussed above are important. With the specified FDMA, it is then possible, for example, that two channels be operated in parallel, in which case one corresponds to the first case of higher allowed energy and The two correspond to the worst case scenario considered. The optimal symbol is therefore quite different for the two channels.

c) Interfered channels As a conclusion to the example, consideration is given to channels that suffer from very severe multipath propagation and / or additional interference signals. In that case, the quality of the received signal is highly dependent on the selected expansion of the signal. Since energy balance management involves its parameters directly so that the maximum bandwidth can always be used, the symbol energy increases as the time duration increases and at the same time.

  The worst case is maintained, but in the best case the highest possible data rate is transmitted, so that the best use of the channel characteristics is important for optimal use of channel resources. Absent. Thus, it is possible to significantly increase the channel capacity of the network, as will be described in more detail below.

  The above example is shown as follows. Desirably, energy balance management involves multidimensional optimization of all physical parameters, which define channel resources, time axis, frequency axis and maximum transmit power.

  The use of typical telecommunications and its realization in accordance with the state of the art is shown below in order to illustrate the physical boundary conditions in the transmission channel and to discuss the results according to the invention. Rather, it will be described in detail with respect to 2.

In wireless transmission methods, the situation occurs when the permissible energy per symbol for free space propagation decreases approximately according to four dimensions. As a simplified assumption, in this example it is assumed that only one modulation mode is used and no higher stage modulation process is employed. It is further assumed that a symbol is always radiated for each subscriber with the same duration T _ref and the same transmit power P _send .

その関係はカーブ２０によって図２に再現される。 FIG. 2 now shows a diagram in which the received energy E _receive is plotted as a function of the distance r between the transmitter and receiver of the wireless transmission network. The distance r is plotted on the horizontal axis, and the received energy E _receive is plotted on the vertical coordinate. The dependence of the function between the received energy and the distance r between the transmitter and the receiver follows.

The relationship is reproduced in FIG.

The noise power density is shown parallel to the horizontal axis in the form of a dashed line 22. Also shown in parallel with the horizontal axis is the magnitude of the minimum symbol energy E _min required to achieve the reception specific bit error rate BER and predetermined by the modulation mode used. Is a solid line 24 that identifies The constant symbol duration T _ref is shown as a bar 26 having a width parallel to the second horizontal axis 27 of the time axis.

In this simple model system according to the state of the art, there is exactly one distance r _ref between the transmitter and the receiver, where the received energy E _rec is exactly required for recognition. Corresponds to the minimum value E _min . Bar 29 shows the minimum received energy E _min , which leads to still accurate reception at a distance r _ref between the transmitter and the receiver in the cell.

If the network is currently scaled based on a worst case scenario, i.e. in relation to transmit power and balance links, the minimum symbol duration is determined, and the minimum symbol duration is When multiplexed with maximum transmit power, it gives maximum transmit energy and then gives receive energy to all nearby users, so that the symbol duration is too large. A receiver located at a distance shorter than r _ref with respect to the transmitter receives more energy than required. A receiver located at a distance greater than r _ref with respect to the transmitter receives energy that is not sufficient for recognition of a symbol with a scheduled BER.

From the transmitter perspective, for r <r _ref , the region of received energy 28 between the straight line 24 (E _min ) and the distance-dependent curve 20 is excessively wasted energy. That energy is not required at the receiver for scheduled BER recognition. On the other hand, in the distance range of r> r _ref , the region 30 of received energy between the straight line 24 (E _min ) and the distance-dependent curve 20 is the BER scheduled at the receiving terminal for a given noise power density. Lack of recognition.

  Now, for closer receivers, the transmit power can be adjusted with a power management method based on the state of the art. However, it means that the transmission power of the channel resource is not fully used.

In an energy balance management (EBM) implementation, the symbol duration at maximum transmit power varies, so the energy of the transmitted symbols is adapted to the channel requirements without reducing the transmit power. As long as each subscriber-specific symbol duration and resulting energy packet is transmitted to each subscriber at full transmit power, the energy balance is thus split. Thus, for each user, the optimal symbol duration is calculated by the received power so that only the symbol energy is applied to the transmitter, which symbol duration is predetermined for the receiver. Required for reception at error recognition rate. It is characterized by E _min in FIG. Transmitters may apply symbol energy for those receivers that are currently in poorer reception conditions, or for another transmission operation to a receiver in a close area, eg, TDMA method Use saved transmission energy by energy balance management in the context of. As such, the transmitter range can be increased through energy balance management.

  It is therefore one of the additional resources available at the other terminal to save subscribers that are just outside the cell and that the base station can no longer reach in the case of current technology based methods. Make better use on the terminal.

  The change in symbol duration is limited downward. The shortest symbol duration corresponds to the maximum bandwidth that limits the transmission channel as an additional parameter.

  FIG. 3 shows the results of the method according to the invention and shows a bar graph plotting transmit and receive power relative to the time axis for various examples. Each received energy is first illustrated, for example, by the front 42 towards the viewer looking at this figure, the received power is determined by its height along the y axis, and the symbol duration is on the x axis. Determined by its width along. The transmitted energy corresponding to each bar of received power is illustrated in the form of a background, eg, the front face 46 of the hatched bar 48. The transmit power and receive power bars that are related to each other are naturally associated with the same symbol duration and are shown as the same range along the time axis. However, the bars differ in height and the received power is always below the associated transmit power.

  Different bars shown in a side-by-side relationship along the time axis correspond, for example, to receivers that differ in distance, and that distance is from the transmitter in the direction of the time axis, or data assigned differently. Increase from the speed receiver. Attenuation effects that are common to all illustrated examples and that depend only on distance are assumed to apply. The same BER should be made available to all receivers as an additional boundary condition. In order to make it possible, the received energy must always reach the value Emin. All cubes that are placed at the front and that represent the received power as a function of time have the same area content in front in FIG. For this purpose, lower power symbols are received, and therefore a receiver at a greater distance from the transmitter communicates with the symbol with a corresponding longer symbol duration.

  The third coordinate (bar depth) represents the bandwidth used in this case, which is set as an additional parameter for the channel. It is shown here as constant so that even if there is a variable duration for the symbol, a suitable expansion effect can be found, this provides that the full bandwidth is used. .

In the method according to the invention, as shown in FIG. 3, the transmitted data symbols are fluidly adapted in terms of energy as long as their time durations are adapted. In that regard, the transmitter is now operated in such a way as to always radiate the maximum allowable transmission power on each channel, as shown in FIG. 3 by the same transmission power for all examples. . The symbol, i.e., the reception quality remaining remains the same, that is, the same received energy E _min, to give to the receiver in question, depending on the current state of the transmission channel, the duration of those bits associated Fluidly adapted over time.

  In that regard, according to the present invention, a higher or lower modulation stage can be additionally selected in the same symbol duration, since more or fewer bits of a bit are transmitted in one symbol. Is possible. The minimum energy is shown dependent on that point in each modulation mode.

  The embodiment for energy balance management described above will be further described in more detail with reference to FIGS. 1-3, taking the main aspects for that purpose.

In wireless transmission methods, the situation occurs when the received energy per symbol decreases in approximately four dimensions of distance with respect to free space propagation. In contrast, the minimum energy required for reliable reception of symbols depends only on the selected modulation and is therefore constant. Therefore, at the maximum planned transmission power, the maximum cell radius is determined by the distance r _ref in FIG.

  If the network is sized based on its worst case, that is, maximum transmit power providing maximum transmit energy, the maximum multiplexed symbol duration is related to transmit power and link budget. If determined, the received energy, as well as the symbol duration, is excessive in the case of all closer users.

  When using power management, the transmit power can then be adjusted downward so that the condition is assumed that the transmitter is adapted to the situation. However, this means that the channel resource transmission power is not fully used. In that case, energy balance management can be advantageously applied due to the reduced symbol duration. It performs a significantly higher data rate and the channel occupancy duration is reduced.

The optimal symbol duration is calculated for each user. In a preferred embodiment, according to equation (1), the symbol duration T _symbol is determined at the transmitting terminal. Its fluid control of symbol duration according to reception quality is possible in principle for any system.

  However, what is important is a problem related to optimal use of bandwidth, since symbol bandwidth generally changes simultaneously with fluid symbol duration. On the one hand, the respective bandwidths can be fluidly adjusted by performing an FDMA procedure where the bandwidth is fluidly divided according to the demands involved. Implementation of such a method in hardware terminology is very complex and expensive. In contrast, such a fluid split can be implemented with a software defined radio.

  Moreover, as long as a sequence represents a symbol, defining the shortest symbol (chip) in relation to the bandwidth and forming a data symbol arranges those many consecutive chips. Is possible. And energy balance management is combined with expanding frequencies. That case involves the quantization of fluid changes in the duration of the symbols by the chip used.

  However, chirp signals are particularly suitable for use in that they can cause a distinction between frequency expansion and time expansion. In that case, the shortest pulse in relation to the bandwidth is generated, and the frequency extension acts in a procedure where those pulses are extended to any duration within the time extension. And according to the energy required, the expansion of the pulse can act fluidly.

  As long as the individual chirp signals are in a superimposed relationship with each other in time, a high data rate is achieved in that way. Depending on the respective degree of superposition effect, the maximum transmit power that the user can use is thus divided so that each chirp signal gets only fragments.

  It is possible because the symbols are compressed into short pulses at the receiver (its maximum is at the zero position of the other pulses). Those si-shaped pulses naturally reflect the bandwidth used.

  Also, in this case, there is an increase in symbol energy quantization as long as fewer symbols are superimposed on each other so that the power of the individual symbols is gradually increased until no symbol overlap occurs. The result is that the compressed pulses are at progressively increasing distances relative to each other and more zero positions remain empty.

  The dynamic allocation of symbol duration is limited downward by bandwidth. It predetermines the shortest pulse that can be used for modulation. However, on the other hand, there are no restrictions, ie the symbols may be very long.

This will be described again with reference to FIG. The current cell size is described by the point r _ref where further signals can be received. Any other reception beyond that point is not possible with conventional systems. Therefore, a user who is just outside the cell must set up a new cell. It results in very high costs, especially in the case of local loop (WLL) configurations. The energy balance management with energy modulation described here allows even the user to be longer and as a result, more service can be provided from the same base station with symbols that can bear more energy. To do. It therefore provides a fluid expansion of the cell in the individual directions that the user is to be found. It is a characteristic that cannot be obtained by other channel management methods.

  The generation of long symbols at the transmitter often does not cause any difficulty. In contrast to receivers, an important issue involves receiving long symbols with short bandwidth, especially if FDMA is used and given the exact frequency. In general, it is more appropriate here to spread the symbols and use the correlation receiver. It applies equally to CDMA sequences and chirp signals.

  These receiver types also basically correspond to conventional matched filters used for optimal transmission.

  Fluidly energy modulation and the resulting change in symbol duration means that this filter must also be fluidly adjusted. This can also be implemented in the form of a software defined radio.

  The distinction between base stations and subscribers is also essential for energy modulation applications. In general, bandwidth and power are limited for telecommunications channels. Thus, it enables the subscriber to radiate the optimum symbol length with full power and corresponding frequency modulation. The frequency bands required for that purpose must be previously enabled so that users do not interfere with each other.

  In the opposite case where it is not easy to divide, the channels to the individual frequency bands simultaneously mean to divide into the maximum transmit power, since the sum of all transmit powers over the frequency does not exceed the maximum allowable power. Calculates the fluidly optimal energy modulation in each network, taking into account the known clear link between transmit power and symbol duration and bandwidth, so that the maximum channel capacity is applied to the network It is possible to do.

  The operation for determining the set value is described below. As discussed in more detail above, energy balance management is based on a receiver-specific manner, eg, transmit energy that is adapted in connection with a base station or access point. Thus, for example, higher stage modulation is implemented in good transmission conditions, but symbol duration increases in poor transmission conditions.

  In order to be able to control this method automatically, the necessary adjustment values must be verified and an efficient modulation must be adapted between the transmitter and the receiver. There are in principle various ways to do it. The power at the receiver is ascertained and, as a result, the received energy is well known for the corresponding symbol, and then can be inferred for all other available symbols, so usually The power management methods currently available can be applied for energy balance management. Two principles are described in detail here as an example.

  The received power can be measured with a simple RSSI measurement (radio signal strength indicator) in the receiver. As such, the reception quality is well known and it is possible to adjust the optimal modulation and / or symbol duration and / or extension between the base station and the subscriber. In that respect, the values of base stations and subscribers are generally different because different interference phenomena occur at various locations.

  Second, the transmission quality can be determined by measuring errors in the frame if, for example, an error recognition code is used. The modulation and / or symbol duration and / or extension can then be changed gradually until optimal transmission efficiency is reached.

  Adjustments can be continually readjusted in existing connections or ongoing data communications without blocking transmission.

  In contrast, making a connection over a cellular network is more difficult. Here, the subscriber sends a request to the base station on the access channel. Since the modulation used is known, it may not be received at the base station.

  There are also various solutions here. First of all, it is always possible to use a physically rugged connection that must always work in a correctly sized network. However, this entails wasting resources.

  Another possible option is to set up many receivers at the base station so that various modulation modes are allowed on the access channel and each subscriber starts transmitting at the last used modulation. . Second, in parallel reception, there is one that always tunes to the transmitted modulation.

  In general, repeated queries on the access channel are also possible, in which case the modulation modes and / or symbol durations and / or extensions that can be imagined are systematically checked. Efficient algorithms can be considered as already used in systems that currently use various carrier frequencies for data communication.

  The same problem occurs in the case of a CDMA system where a specific extension code must be fluidly assigned to each user before the actual connection (communication channel) is ready.

  Similarly, it is possible in energy balance management to determine the optimal symbol to be used for transmission before the optimal symbol is used in the actual communication channel.

  In that regard, the transmitted symbols can be different from the received symbols because loss and interference can be different on the channel between the uplink and downlink.

  FIG. 4a) is a diagram illustrating a wireless local loop network 50 with a base station BS. The subscriber stations are identified as SU1 to SU5 and Sun (SU: subscriber unit). Further, propagation obstacles for transmitter radiation are identified with reference numbers 52-58. The obstacles 52 to 56 are, for example, tall buildings, and the obstacle 58 is, for example, a mountain range such as the Alps.

In comparison with the previous example, the transmission energy here is no longer dependent exclusively on distance, but on another factor. In many cases, the required transmission energy is determined by the following important parameters: Furthermore, however, parameters that are not so important to those skilled in the art are not included in the following list.
> Modulation mode
> Distance between transmitter and receiver
> Interference and noise
> Required BER (eg for specific security applications)
> Modulation propagation (visual line, no visual line)
> Antenna characteristics

  The cell size is determined in advance by the maximum (allowable) transmission power of the base station (BS) based on a known method. It is symbolically shown in FIG. 4 by a circular line 60. Within a cell, individual subscribers are sometimes located closer to the base station (ie, SU5) or sometimes further away from the base station BS (ie, SU4). On the other hand, additional signal distortion occurs due to multipath propagation as well as signal shadowing by large buildings 52-58. Mountain range 58 is a difficult obstacle to overcome because it cannot reach subscriber SU3, which is not visible from base station BS, across the mountain range.

Due to the multiplexing of the existing transmission channels, individual subscribers are successfully reached, others are poor and none at all. FIG. 4b) in the form of a bar graph shows the transmission power required for a certain symbol duration in the corresponding previous method and the transmission power required for transmission to the respective SU. The bar numbering corresponds to the subscriber number. In one example, bar 1 symbolically represents the transmit power for subscriber SU1. The two subscribers SU1 and SU2 are outside the range of the base station BS and can only be reached if the level is higher than the allowable peak power P _send .

FIG. 4c) shows the solution achieved with bit duration management, in contrast, for comparison purposes. Reception at the same reception energy at the subscriber involves using each appropriately adapted transmission energy set by application of the symbol duration at the maximum transmission power P _send in each case. The existing channel capacity is differentiated within the network for each subscriber based on the characteristics of the different channels. Its basic physical characteristics, which were common at the time, are essentially different from network organization methods that attempt to allocate the same channel capacity (or data rate) to all subscribers of a cell. Constitute.

  As long as the optimal data rate can be fluidly provided to each subscriber in the network with an acceptable error rate, new tasks can now describe telecommunications tasks. As a result, the symbol energy required for that purpose decides to adjust the value of the network. It follows an approach where the transmitted symbols may not be fixed and they must be fluidly changed at the transmitter, resulting in a problem for the selected modulation, depending on the transmission channel Subscribers always receive the required reception quality described by, for example, an error recognition rate or a clear bit error rate.

  The physical principle involved only when the transmitted data symbols are fluidly adapted in terms of energy, however, makes it possible in a fluid channel, ie optimal energy modulation or optimal bit duration. Management is performed or energy balance management is performed for the network organization.

Reference is now made to FIG. 5 to consider a general implementation that is typical of wireless connections. The subscriber number N _channel is supplied from the base station at the same time, where a typical multiple access method can be employed. The following calculation is based on a cell sized such that the farthest user is at a distance r _ref [m] from the transmitter, and a predetermined symbol duration T _ref [s] and maximum transmit power P _{With send} [W], energy E _min [Ws] necessary for stable data reception is received.

In general, it is assumed that data is transmitted in an enlarged manner. The situation therefore means that the used bandwidth B [Hz] is greater than the reciprocal of the symbol duration T _ref [s].

  The selected modulation mode is the same for all subscribers in the target cell, and it is further assumed that antennas with isotropic directional characteristics are used and that the propagation of electromagnetic waves takes place in free space. . All these assumptions are by no means a prerequisite for energy balance management. They are only useful in performing the calculations described here in a simple formula.

The target cell to be considered is given by a base station that supplies a fixed number of predetermined channels, for example, in a TDMA or CSMA multiple access method. Each of these channels has a data rate R _ref [bits / s] intended to exactly correspond to the data rate required by the subscriber.

  As long as we refer to formulas not mentioned here in the following description, they can be found by their specific formula numbers in Tables 5 and 6, respectively.

  The limiting physical values in the cell being considered are bandwidth and maximum transmit power. The received power for each subscriber in the cell depends on its distance to the base station to the fourth power due to assumed free space propagation.

  The received power is a decisive setting in this example, which is uniquely determined by the position of each user. For the reception of transmitted items of information, however, it is not the decisive power, but the received energy per bit calculated from the product of the received power and the symbol duration. In an optimal system, the value should therefore be kept constant so that the required error rate is observed.

In order to make the reference system in question a robust system with a fixed symbol duration T _ref [s], its sizing is designed to ensure reception of information at the maximum distance r _re f [m] Thereby, the minimum energy per symbol E _min required for reception is determined in advance. In that regard, first of all, in the reference system, it is assumed that each symbol includes only 1 bit as an information amount.

  In currently common transmission methods, the energy of the received symbols is kept constant by the decreasing transmission power. As such, available channel resources are wasted wastefully. Currently, it is to be shown here how easily resources can be used by applying energy balance management.

The following calculations are based on system comparisons, i.e. using energy budget management, where the relationship of the robust reference system to the flexible system is decisive. Now, reliable reception of messages according to the selected modulation mode requires energy E _min [Ws] which is related by channel loss to transmission energy.

  In the first approximation, where the distance r [m] decreases to the fourth power, however, it is always limited upward (ie limited by a small distance) for physical reasons. Formulated in general terms, the following applies power radiation under the stated conditions.

For the target cell, its value can easily be stated to the minimum energy E _min [Ws], multiplied by the symbol duration (formula 21 in Table 5). Currently, the transmitted symbol duration does not change the broadcast interface, so in general the received energy per symbol can be viewed as a function of the transmitted energy (formula 22).

In the classical way, the base station of the target cell currently transmits signals to all subscribers with the same energy, thereby causing excessive power or energy to be transmitted to the base station, as mentioned at many points above. As long as it is sent to a nearby user, the available resources are partially wasted. Many users benefit from “quasi-parallel” relationships based on multiple access methods. The number of active users in the target cell corresponds to the channel number N _channel of the access method at that point.

The radiant energy E _send [Ws] per symbol is defined as the product of the maximum transmission power P _send [W] of the target system and the symbol duration T _ref [s].

Considering the provisions of the law, in total, the energy radiation allowed for the base station is shown below.

That energy balance is therefore available to the cell. That is exactly the point that energy balance management comes into play. Each subscriber simply sends the transmission energy necessary for the subscriber to receive a signal with energy E _min [Ws].

  In a general theorem, the number of possible active users in the area is critical when using energy budget management, which can generally be explained through the user density associated with the area. In the following, the density is assumed to be a constant (formula 23) and is normalized relative to the possible target cell. When the density is constant, the value does not change in relation to the area, so r and ψ in the formula are only used formally as variables describing the position.

  Application of energy balance management means that as long as each user receives the minimum energy per symbol, regardless of his location, the resource is currently being used appropriately. Since the received energy is constant, the energy balance management system must therefore change the transmitted energy depending on the distance (formula 24).

  The energy radiated by the base station as a statistical average is the integral over the density of active users associated with the area (formula 25), in each case multiplied by the respective transmission energy.

  The integration over a circular area A of radius rcell [m] gives a simple formula (26), which is then compared to the values already described for classical cells.

First of all, for the situation where both cells are of the same size (ie r _cell = r _ref and the situation is identified by 64 in FIG. 5). The energy considered and radiated at the base station should be the same in both cases.

Under these circumstances, there is a direct relationship between dealing with equations (12) and (26) for formula (21) and in both cases the number of active channels.

For all cases that are actually relevant, the formula is further simplified substantially by the approximation (27). This means that, for energy balance management applications, the number of channels N _{channel_EBM} is doubled compared to the conventional number N _channel with the same cell size and the same data rate per channel (R _EBM = R _ref ). Will give you a simple relationship.

This is shown in FIG. Alternatively, it can be doubled with the same number of channels N _{channel_EBM} = N _channel for the data rate per subscriber. R _EBM = 2R _ref. Thus, the introduction of energy balance management leads to a 100% increase in planned cell efficiency. It is illustrated in FIG. 5 in connection with cell 62.

  As an example of a further formula, the density associated with the active user's area is quoted for cell 66 to consider the case where it should be the same for both cases (formula 28).

Therefore, based on the already inferred results, it is clear that less energy is radiated by the base station to the cell of interest when using EBM. For the above purpose, where r _cell is replaced by r _EBM , in formula (29), the energy difference can be used to enlarge the cell so that r _EBM > r _ref , which in cell 66 A related illustration is shown in FIG. The determination of formula (29) leads to a more complex formula as a quotient containing only the proportion of the target cell, which for all subscribers when using energy balance management for maximum cell expansion Provide the same quality. By referring to formula (27), the formula can be simplified again, giving:

The cell 66 is thus expanded with a radius r _EBM of only 20% at the same quality of service (data rate) in terms of all active subscribers (R _EBM = R _ref ). It looks small at first, but as such, the total number of channels is increased from N _channel to the next value.

As a result, the number of channels N _{channel_EBM} in the cell 66 can be increased by 41%. This advantage is shown schematically in FIG.

  The above derivation should now be considered again in more detail now regarding the technical realization of EBM. Obviously, subscribers close to the base station generally have an available channel with a low channel loss for further remote subscribers. The above guidance process now indicates that less energy must now be radiated by the base station for reliable reception of the selected symbol.

  The question is how can we do it technically now. In that regard, there are two methods: symbol duration change and modulation change.

  The following derivation is equivalent to both methods, but ultimately, the energy balance management described optimally performs in principle by fluid changes in symbol duration and / or by higher stage modulation It shows that it is subject to different restrictions so that we can emphasize what we can do. A preferred change involves the proposal of a combination of both methods, where a stunning change in symbol duration is implemented until it can no longer be tracked due to limited bandwidth, and then more High stage modulation is applied.

  For any event, the formula derived above (26) represents the limit of improvement that can be achieved in terms of energy budget management.

First of all, EBM allows fluid application of symbol duration. The transmission energy per _symbol is a product of the transmission power P _send [Ws] multiplied by the respective symbol duration T _symbol [s]. Changing the transmission power to a value less than the maximum allowable value means wasting channel resources. Its value is therefore constant.

The symbol duration can be varied so that the transmitted energy is different for individual subscribers. Therefore, the following formula is applied to the above case.

Where E _min [Ws] indicates at least the energy required at the receiver to reliably detect the symbol, and T _ref [s] is the previously considered object with classical cell organization Symbol duration in the cell.

  A fluid change in symbol duration is a very suitable way to fluidly change symbol energy at the transmitter.

  In general terms, the bandwidth required at least for the transmission of a symbol is equal to the reciprocal of the symbol duration. Therefore, that first approach means that the required bandwidth is not available. Therefore, this approach is easily faced with limitations that prevent optimal use of the energy balance management system.

In addition or in addition, it is possible to make fluid changes in higher stage modulation. This second embodiment is rather complex and must therefore be described in more detail. The formulas used so far involve, for the general case, the value E _min that identifies the energy that must be arrived at with the selected modulation at the receiver, so that the receiver has one bit of information. Are recognized with an appropriate degree of certainty. However, in the general case, a symbol can contain many bits.

  The relationship between symbol energy and bit energy, or the amount of information in a symbol, arises from the employed modulation. In situations where symbols have excessive energy at the receiver, energy instead uses symbols to change the modulation mode and to carry more information and hence require more energy Could be used to do.

As a simple example, consideration will be given to the situation where the target cell involves the use of BPSK modulation where each symbol corresponds exactly to one bit. The required received energy is indicated by E b — _min , where the index b is for indicating 1 bit.

For example, when changing from BSPK to QPSK for the amount of information related to symbols, it changes from 1 to 2 bits. At the same time, the required energy required for reliable reception of symbols increases. In that case, the following formula applies:
E _min = 2 * E _{b_min}

  Thus, as long as the modulation is adapted to the factors involved, and it is the amount of information in the symbol, not the symbol duration being changed, the energy balance management procedure ensures that the energy present is completely at the receiver. Accompanies a situation that can be used.

に変換することができることは通常のケースである。式中のMはシンボルの様々な「状態」の数を示し、log₂(M)は、１シンボルあたりのビット数を示し、すべての状態は、同じ確率を持つ。また、一般的な場合では、ここで異なった確率を考慮することができる。 As a rule, the energy corresponding to the symbol energy per bit:

It is a normal case that can be converted to. M in the equation indicates the number of various “states” of the symbol, log ₂ (M) indicates the number of bits per symbol, and all states have the same probability. Also, in the general case, different probabilities can be taken into account here.

In generalized terms, it is now considered that the modulation mode is always used, so symbols with a higher amount of information are statistically generated for each bit as required by the selected target cell. On average, energy E _{b_min} is required.

In this embodiment, only the modulation of the symbols is changed. The energy emitted from the transmitter (or base station) is then always the same for each subscriber.

This apparently corresponds to the reference case, but in the EBM system, the amount of information about the symbol is changed.
This specifies itself if the transmission energy per bit is specified.

  Depending on the loss that occurs, it contains a higher amount of information, ie a larger M, for closer subscribers, while a smaller M for more distant subscribers. In contrast, the received energy per bit always corresponds to a minimum value (formula 31), so that there is a function of the transmitted energy for the subscriber in question in relation to the distance.

  Equalizing the two equations (20) and formula (33) leads to a clear description of the modulation that should be selected at the transmitter (formula 33), and for this formula 33 a good approximation was given. It may be assumed that the number of discrete “states” of the symbol M (r) can be varied sufficiently to provide a continuous function.

  Each subscriber currently does not need many symbols, only bits for the scheduled amount of information transmission. Thus, the energy required by an individual subscriber depends only on the number of bits and the energy of the individual bits, so that for energy balance management applications, this is the sum of integrals for equally entitled subscribers ( Concerning Formula 34).

  The integral can be easily calculated with the formula (35) specified above and provides the formula (26) already included in the previous general derivation.

  Since it is necessary to distinguish between bit and symbol energy, only the minimum energy indication is changed here. In contrast, formula (34) further applies to the classical situation. It corresponds positively to the previously specified general inductive equation, and it can finally be emphasized that the energy balance management system already described can in principle be additionally implemented with higher stage modulation.

  To consider time division multiple access (TDMA) as a further embodiment, reference is made to FIGS.

6 and 7 show the division of a given time period T _FRAME into time parts 70-76, 80-88, and 80′-84 ′, respectively, as time zones. The conventional TDMA method involves dividing a subscriber on the time axis according to a time zone assigned to each subscriber. These time periods occur periodically at the time interval T _FRAME , after which each subscriber is assigned a new time period. Portion 76 in FIG. 6 characterizes the duration in many more time zones with duration T _channel .

  Currently, in the network, channel conditions are different for individual users, so the EBM method must apply different symbol durations and different modulations in order to make optimal use of resources available. It is assumed that it will not be.

  In that case, the number of transmitted bits per time slot is fixed, so that the subscriber is guaranteed a data rate that is not changed, and thus the time period duration is dynamically changed according to the channel conditions. This can be seen in FIG. 7 by looking at time zones 80-88 and 80 ', 82' and 84 'of different widths. The composition of these time zones with different lengths is relatively simple in TDMA.

  As already explained in many places above, the classical system is designed for the worst case and, as shown in FIG. 2, the closer stations receive too much power, so In general terms, the packet duration decreases with respect to the target cell. The efficiency of EBM is thus immediately evident.

  EBM execution can now affect, for example, fixed symbol duration and, consequently, unchanged bandwidth due to higher stage modulation, so fewer symbols and consequently shorter time periods Is required to transmit some of the defined information. Reference may be made here by way of an example of QAM such that the amount of information about a symbol can be gradually increased from QPSK to eg 256QAM.

  At the receiver, the required changes to the detector are relatively small. In addition to pure phase detection, the amplitude detector further requires QAM.

  To determine the optimal symbol of EBM, first the simplest modulation is applied to the access channel, and then higher stage modulation is gradually applied, so long as that symbol has a higher amount of information, It is possible to use simple rules here. And the amount of information can be increased until the symbol with the largest amount of information is used or when the transmission quality (determined by the bit error rate) no longer meets the demands involved .

  Instead, it is possible to measure the power of the received signal and to quickly determine the most preferred symbol based on that information without gradual rules.

  The optimization should be performed individually for each subscriber. Then, based on the length of the channel specific time zone, a new organization of TDMA is needed, where the time mark for the start of each time zone is fluidly adapted to changes in the network. The

In that case, so many time slots can be allocated until the scheduled time frame T _FRAME is properly met.

  Furthermore, due to interference effects or shadowing, a situation occurs where the energy of the individual subscriber's symbol is too low. The classic TDMA method then does not allow any connection.

  In those situations, for example, the period is doubled step by step using the simplest modulation until the maximum symbol duration is reached or until the transmission quality (determined by the bit error rate) meets the requirements. By doing so, the length of the symbol duration has to be increased additionally.

  In that regard, in order for the current symbol energy to be optimally used, the receiver must adjust its matched filter as possible.

  With the combination of the two adjustment orders, the transmission quality for all TDMA subscribers is significantly improved by introducing the EBM procedure.

  To illustrate the application of EBM to the MDMA method, reference is now made to FIG.

  The generation of long symbols at the transmitter often does not cause any difficulty. In contrast, receivers may suffer significant problems in receiving long symbols of small bandwidth, especially if FDMA is used and the frequency must be set accurately.

  In general, it is more preferable to expand the symbols and use a correlation receiver. It applies equally to all pseudo-noise sequences (maximum length sequence (m-sequence), gold code, etc.), gold code, etc., and to all types of chirp signals.

  Also, these receiver types basically correspond to the classic matched filter used for optimal transmission.

  The filter must also be fluidly adapted to account for fluid energy balance management and consequently symbol duration changes. This can also be implemented in the form of a software defined radio.

  At that point, the chirp signal assumes a specific position. There, individual signals can be superimposed over time, so that physical symbols are of different duration than logical symbols.

  At the receiver, the symbols are again separated from each other by a compression filter and waveform processed to provide short pulses that maintain a spacing of n · δ [s] from each other.

In that case, the physical symbol duration T _Chirp >> δ should be kept constant if the duration T _symbol and consequently the data rate of the logical symbol is changed by energy balance management .

  Because of the chirp signal, the bandwidth B [Hz] used always remains the same, so there is only a change in the included gain and the duration δ of the compressed chirp signal is the inverse of bandwidth B. If so, the change is calculated as B · n · δ = n.

  The decisive advantage in that respect is that the receiver can always use the same correlation filter or the same correlation process.

  This situation is shown in FIG. 8a. There, the duration of the smallest logical symbol is specified by δ [s]. Its value corresponds to the reciprocal of bandwidth B [Hz]. The expanding frequency is therefore initially 1 and gradually increases, such as 2, 4, 8, etc., due to the physical pulse duration δ maintained and the gradually reduced repetition rate.

  In that case, the energy contained in the physical symbol gradually increases as the amplitude of the pulse increases.

  Time evolution is performed before the signals are emitted, so that the transmitted signals are of almost constant amplitude and consequently constant transmission power. The unfolding operation can be performed, for example, with a distributed group delay time filter, so that each narrow pulse is replaced with a chirp signal of a predetermined duration and bandwidth.

  Since a supplementary process takes place at the receiver, the chirp signal is again compressed into narrow pulses.

  The form of signal development has already been described in detail in patent specification DE 199 37 706, and in that form it can be used advantageously for the application of energy balance management procedures.

The amount of transmitted symbols in that particular case of MDMA is here distinguished in the following respects. That is, n different symbols can be used, n ≦ T _chirp / δ, the energy of the symbol is an integer multiple of the shortest symbol, the expansion factor also increases simultaneously with the energy, and higher stages The modulation process (eg PSK, QAM or ASK ...) is superimposed on the shortest symbol, so there are many symbols with higher information content.

  The longest, most robust, and most energetic symbol is used in the access channel for a large expansion effect and the maximum data signal rate is reached or the transmission quality related requirements are met As long as higher data rate symbols are gradually tested until there are no more, it is possible to employ a simple restriction here to determine the optimal symbol for EBM.

  And in the situation where the shortest symbols are used, the process of higher stage modulation is further used to assign a higher amount of information to each symbol. The amount of information can be increased until the maximum information symbol is used or the transmission quality (eg determined by the bit error rate) does not meet the relevant requirements.

  Instead of gradually passing the adjustment, it is possible to measure the power of the received signal based on that information instead, in order to immediately determine the most preferred symbol.

  When the channel characteristics are generally quite different, optimization of the energy balance is necessary for each subscriber in the network.

  FIG. 9 shows an implementation of a transceiver configuration 150 for wireless connection with energy balance management.

  The signal received by the antenna 152 is first amplified by a low noise amplifier (LNA) 154 and then sent in the receiver 158 simultaneously to the RSSI detector 156 and the demodulation and detection unit 159. . The microprocessor 160 can calculate the received energy from the signal provided by the RSSI detector 156 and then determine the optimum signal from which the highest data rate is obtained with the given reception quality. And at the same time receive with full confidence. The output signal of the demodulation and detection unit 159 is also passed to the microprocessor 160 for further processing.

  The type of symbol used can be agreed with the handshake protocol between the two stations, in which case the most reliable connection can be chosen during the matching operation. That is, transmission is performed with the longest symbol.

  Further, according to the procedure, the transceiver configuration in FIG. 9 has a transmitter 162, which is connected to the antenna 162 and also connected to the microprocessor 160. Optionally, the assembly may include a memory 164 with stored parameters or signal patterns of data symbols of different duration and modulation. The transmitter includes a symbol generator 163, which is connected to the input side of the microprocessor, and an amplifier (PA) is connected to its output side.

  Desirably, the two intercommunicating transceiver configurations should be of a flexible design configuration. It is even possible to obtain optimal results with a transmitter 162 that emits one type of symbol in the content of the connection and a receiver 158 of the same configuration that receives the different symbols.

  A transmission / reception switch 151 is provided for the additional period so as to switch between the transmission mode and the reception mode.

  10-13 show a modification of the embodiment of FIG. In the following description of these modifications, the focus will be on the differences from the configuration of FIG. The same numbers are used for corresponding units as compared to the configuration of FIG.

  In the digital portion 178, the microprocessor 160 can be programmed and controlled through a connected interface 178.

  The configuration of the transmitter and receiver in FIG. 10 is additionally designed for chirp signal generation. For this purpose, the receiver 170 and the transmitter 172 have distributed delay units DDL2 and DDL1 complementary to each other. In the transmitter, the symbol generator 174 controlled by the microprocessor 160 is connected to the input side of the delay unit DDL1. In the receiver 170, the demodulation and detection block 176 is connected to the output side of the delay unit DDL2.

  The created symbol is converted into a chirp signal of the transmitter 172 by the delay unit DDL1. They use the full available bandwidth. At the receiver, the transformation is inverted by a supplemental filter DDL2. The elongated chirp signal is converted into short signal peaks.

  The configuration of the transmitter and receiver in FIG. 11 differs from that of FIG. 10 in a channel estimation unit 182 additionally provided in the receiver portion 170. In that way it is possible to optimize the operation of determining the optimum energy of the signal to be transmitted. Thus, it is possible to directly estimate not only the energy required in that case, but also the required expansion effect, without examining all the available signals due to tedious processes.

  FIG. 12 shows a variation that provides for the generation of a pseudo-noise sequence to expand the signal in comparison with the configuration shown in FIG. For this purpose, an m-sequence generator 184 connected to the input side of the symbol generator 174 is provided in the digital part 178. Now, the possible symbol duration stored is a multiple of the chip duration. Prior to the transmission of the symbols, the necessary part of the m-sequence is superimposed on the symbols by the symbol generator 174, so that the symbols are expanded to the maximum bandwidth. In addition, pulse shaping is additionally provided in the pulse shaping unit 186 so that the planned bandwidth is observed.

  FIG. 13 shows a variation of the form of the transmitter module 190 in the form of a software defined radio with programmable functional blocks, which blocks in terms of their functions are the above-described units of the transceiver configuration described here. Corresponding to

  Another difference associated with the configuration in the previous figure is that this configuration has a chirp signal generator 192. An analog-to-digital converter converts an incoming analog signal into a digital signal for further processing in the digital part. A digital / analog converter 196 is provided for transmission.

An overview of the parameters and symbols used

Official collection of calculations related to Figure 5

FIG. 5 is a diagram useful in explaining the term “energy balance” of a transmitter based on the relationship between spectral and transmit power density, frequency of transmission and magnitude of time. FIG. 5 is a diagram filled in as a function of received energy, distance between transmitter and receiver, in a manner based on current levels. In order to disclose an embodiment, the transmission power and the reception power at which the reception energy remains the same as a function of time for different receivers are shown. In order to compare the power management method and the energy balance management, the diagram of the wireless local loop is shown. Another figure for comparing power management method and energy balance management is shown. It is a figure which shows the data frame by the TDMA method based on the present technique. It is a figure which shows the data frame by the TDMA method based on energy balance management. A compressed symbol (a) with different frequency expansion and an overlapped time expansion signal (b) are shown. FIG. 4 shows a block diagram of different embodiments of the transceiver structure. FIG. 4 shows a block diagram of different embodiments of the transceiver structure. FIG. 4 shows a block diagram of different embodiments of the transceiver structure. FIG. 4 shows a block diagram of different embodiments of the transceiver structure. FIG. 4 shows a block diagram of different embodiments of the transceiver structure.

Explanation of symbols

1
150: Configuration of transceiver 151: Transmission / reception switch 152: Antenna 154: Low noise amplifier (LNA)
158: Receiver 156: RSSI detector 159: Demodulation and detection unit 160: Microprocessor 164: Memory 163: Symbol generator 178: Interface

Claims (83)

A method of transmitting a number of symbols each having at least one bit from a transmitter to at least one receiver with at least one channel and a predetermined transmission power,
Symbols are transmitted and received so that the receiver-specific transmission energy is symbol reception at the receiver side, and the received energy corresponds to the upper limit value associated with the receiver or a lower error recognition rate. To achieve the highest possible bit rate, depending on the current transmission state between the transmitter and the receiver, at the same time, the symbol duration, the transmitted bit per symbol A number or a symbol duration and the number of transmitted bits per symbol are employed. A method of organizing a network for transmitting symbols using at least one channel and a predetermined transmission power for each transmission of a number of symbols having at least one bit from a transmitter to at least one receiver;
The receiver-specific transmission energy is symbol reception on the receiver side, and the reception energy corresponds to the upper limit value related to the receiver or the value of the generated error recognition rate that is lower than the upper limit value. Depending on the current transmission state between the transmitter and the individual receiver, the symbol duration can be achieved, in order to achieve the symbol-transmitted, receiver-specific transmission energy, and at the same time the highest possible bit rate. A method characterized in that time, or number of transmitted bits per symbol, or symbol duration and number of transmitted bits per symbol are employed.   The method according to claim 1 or 2, wherein the symbol duration is applied exclusively.   Three available application options: application of symbol duration, application of the number of transmitted bits per symbol, and application of both the symbol duration and the number of transmitted bits per symbol 3. A method according to claim 1 or 2, comprising the step of selecting from among.   Spectral power density at a predetermined transmit power and / or radiated electric field strength and / or radiated magnetic field strength and / or allowable power radiation amount in a channel-specific manner with time averaging, 5. A method according to any one of claims 1 to 4, wherein a parameter related to one or more of said parameters assumes a limit value corresponding to a maximum allowable transmission energy per unit of time with an allowed radiation dose. .   6. A method according to any one of the preceding claims, wherein the predetermined transmission power is the largest on a time average associated with the technical design of the transmitter.   The method according to claim 1, wherein the transmission power is predetermined.   8. A method according to any one of the preceding claims, comprising the additional step of ascertaining a current value for received energy at a given transmitted energy.   The method according to any one of claims 1 to 8, wherein an RSSI measurement (radio signal strength indicator) relating to the received power is performed on the receiver side and a signal dependent on the measurement result is communicated to the transmitter.   10. A method according to any one of the preceding claims, comprising another or additional step of ascertaining a current value for the error recognition rate.   The method of claim 10, wherein the error recognition rate is confirmed by measuring the number of errors in the received data frame.   The method according to claim 10 or 11, wherein the error recognition rate is confirmed by averaging the number of errors in a number of data frames.   The method of claim 12, wherein the error recognition rate is ascertained by the number of negative received signals from the receiver in a scheduled period.   The method according to any one of claims 1 to 13, wherein the error recognition rate is a bit error rate (BER), a block error rate (BLER), or a frame error rate (FER).   The application of the symbol duration is carried out depending on the current value of the error recognition rate at the receiving terminal or the current magnitude of the noise power density at the receiving terminal. The method described.   The method according to any one of claims 1 to 15, wherein the receiver informs the transmitter of the current error recognition rate or the current magnitude of the noise power density.   The method according to claim 1, wherein the transmitter estimates the current error recognition rate at the receiving terminal or the current magnitude of the noise power density.   The symbol, the number of bits contained in the symbol, or both are the current values between the transmitter and receiver, either on the existing connection or on the ongoing data update, without interrupting the connection or data update. The method according to claim 1, wherein the method is adjusted in a fluid manner depending on the transmission state.   19. A method according to any one of the preceding claims, wherein the change in symbol duration occurs in time, replacing pseudo-continuous, instead of a predetermined time interval.   20. A method according to any one of claims 1 to 19, wherein the symbol duration is applied in a channel specific manner, i.e. for each individual channel used.   21. A method according to any one of the preceding claims, wherein the symbol duration is limited towards short symbol duration values in a channel specific manner by the channel bandwidth.   22. A method according to any one of the preceding claims, wherein the symbol duration is determined from a continuous value spectrum.   The symbol duration is determined from a discrete value spectrum, the discrete value spectrum comprising an integer multiple of the shortest symbol duration possible in a channel-specific relationship. The method described.

The symbol duration T _symbol is determined at the transmitting terminal based on the formula: where E _min is the received energy corresponding to the upper limit associated with the receiver in terms of error recognition rate, and P _send is the maximum transmit power in it, r is the distance between the transmitter and the receiver, r ₀ is the reference distance, and, alpha a method according to any one of claims 1 to 23 is the propagation coefficient.   The selection of the number of transmitted bits per symbol is performed with a currently prevailing value of the error recognition rate at the receiving terminal or with the current magnitude of the noise power density at the receiving terminal. The method according to any one of the above.   26. A method according to any one of the preceding claims, wherein the number of transmitted bits per symbol is adapted in a channel specific relationship.   27. A method according to any one of claims 1 to 26, wherein the application of the number of transmitted bits per symbol is implemented when the shortest symbol duration is already used in a channel-specific relationship.   28. A symbol type with the largest possible number of bits is selected for transmission, and that type does not cause the upper limit of the error recognition rate to be exceeded at the receiving terminal. The method described in 1.   29. A method according to any of claims 1 to 28, wherein the symbols are conveyed in a divided state up to each series of chips.   30. The method of claim 29, wherein the symbols are expanded with respect to a frequency modulated with a noise or pseudo-noise sequence, the noise or pseudo-noise sequence being known to the receiver.   The method according to claim 30, wherein the noise or pseudo-noise sequence is fluidly adapted to the selected symbol duration.   32. A method according to any of claims 1 to 31, wherein the symbols are conveyed in such a way that the available channel bandwidth is fully used.   The method according to any one of claims 1 to 32, wherein the symbols are transmitted in terms of frequency.   34. A method as claimed in any one of claims 1 to 33, wherein the symbols are conveyed in the form of a chirp signal.   35. The method of claim 34, intended for each receiver, wherein the chirp signal from the transmitter is superimposed in time.   36. The method of claim 35, wherein the sum of the chirp signals superimposed on each other and the instantaneously radiated transmit power in time equals the maximum allowable transmit power for each channel.   37. A method according to any one of claims 1-36, wherein the symbols are transmitted in a CDMA sequence.   The method according to any one of claims 1 to 37, wherein the symbol is transmitted in a frame of FDMA method.   40. The method of claim 38, wherein the division into FDMA channels is performed fluidly in such a way as to allocate lower bandwidth to receivers in good channel transmission conditions.   40. The method according to any one of claims 1 to 39, wherein the TDMA method is used on at least one channel.   41. The transmitter according to claim 1, wherein the transmitter is a user's mobile terminal and receives information about a frequency band to be used for transmission from the base station before transmission of symbols to the base station. The method described.   A base station operating as a transmitter checks a signal arriving in a number of modulation modes from a mobile terminal operating as a transmitter, and the modulation mode recognized as being accurate in receiving a signal from the mobile terminal 42. The method according to any one of claims 1 to 41, wherein:   A base station acting as a receiver receives incoming signals from a number of receivers, modulation modes are related to the writing receiver, and a mobile terminal acting as a transmitter transmits symbols to the base station. 43. A method as claimed in any preceding claim, wherein one of the modulation modes available at the transmitting terminal is used for this purpose.   44. A transmitter adapted to perform the method of any of claims 1-43. A transmitter for performing the method according to any of claims 1-43,
A transmission unit adapted to generate and emit a signal representing a logical symbol (hereinafter referred to as a symbol) representing one or more bits; and
Generate and supply a control signal that processes to the transmitter unit the receiver specific transmission energy corresponding to the error recognition rate associated with the receiver or the error recognition rate lower than the upper limit value. A transmission unit adapted to be based on an item of information existing about the current transmission state between the transmitter and receiver of the symbol,
Symbols with appropriately adapted symbol duration, or symbols with appropriately adapted number per symbol of transmitted bits, or appropriately adapted symbol duration and appropriately per symbol of transmitted bits The highest possible bit, depending on the current transmission state between the transmitter and the receiver, in order to generate and supply a control signal that determines the use of symbols with an adapted number for the transmission unit Transmitter characterized in that a control unit is additionally applied for the purpose of achieving speed and receiver-specific transmission energy.   The control unit relies on the current transmission state between the transmitter and the receiver to generate and provide a control signal to determine to the transmitter unit the use of symbols with appropriately applied symbol duration. 45. The transmitter according to claim 44, wherein the transmitter is adapted exclusively for the generation of the receiver-specific transmission energy and at the same time the highest possible bit rate based on alternative means.   The control unit selects one or more of a number of available application options and enters the current transmission state between the transmitter and receiver to create and provide a signal indicative of the determined selection. 47, 45 or 46, wherein adaptation options include application of symbol duration, application of number of transmitted bits per symbol, and application of both symbol duration and number of transmitted bits per symbol. The transmitter according to any one of the above.   Transmit power and / or radiated electric field strength and / or radiated magnetic field strength and / or spectral power density related to allowable power radiation are equal to a predetermined maximum value or limit of the technical design of the transmitter 48. The parameters of any of claims 44 to 47, wherein a parameter that is a maximum value of or related to one or more of the aforementioned parameters is a limit value corresponding to an allowable maximum transmission energy per unit time associated with allowable radiation The transmitter according to any one of the above. 49. A transmitter as claimed in any one of claims 44 to 48, wherein the control unit is adapted to estimate the current error recognition rate at the receiver side or the current magnitude of the noise power density.
  Depending on the current transmission state between the transmitter and receiver, the symbol duration and / or the number of bits contained in one symbol can be fluidly re-determined with existing connections or ongoing data communication. And processing in the same way for the transmitting unit by means of suitable control signals, and the transmitting unit is adapted to perform the defined application without interrupting the connection or data communication. 50. The transmitter according to any one of -49.   51. The control unit according to any one of claims 44 to 50, wherein the control unit is adapted to continuously re-determine a symbol duration in time by changing in a pseudo continuous or predetermined time interval. Transmitter.   52. A transmitter as claimed in any one of claims 44 to 51, wherein the control unit is adapted to determine the symbol duration in a channel specific manner, i.e. individually for each channel used.

The control unit is adapted to determine the symbol duration T _symbol , where E _min is the received energy corresponding to the upper limit of the error recognition rate associated with the receiver, and P _send is the maximum transmit power, r is the distance between the transmitter and the receiver, r ₀ is the reference distance, and, alpha is claimed in any one of claims 44 to 52 is the propagation coefficient Transmitter.   The control unit performs selection of the number of transmitted bits per symbol depending on the current error recognition rate at the receiving terminal or depending on the current noise power density magnitude at the receiving terminal 54. A transmitter as claimed in any one of claims 44 to 53 adapted to do so.   55. A transmitter as claimed in any one of claims 44 to 54, wherein the control unit is adapted to apply a per symbol number of bits transmitted in a channel specific relationship.   56. The control unit according to any one of claims 44 to 55, wherein the control unit is adapted to perform application of the number of transmitted bits per symbol when the shortest symbol duration is used in a channel-specific relationship. Transmitter as described in.   The control unit is adapted to select the type of symbol of the maximum number of bits possible for transmission, which allows the receiving terminal not to exceed the upper limit of the error recognition rate. The transmitter according to any one of the above.   58. A transmitter as claimed in any one of claims 44 to 57, wherein the transmission unit is adapted to emit symbols distributed to the respective series of chips.   The transmitter unit is adapted to emit symbols expanded in frequency as long as the transmitter unit modulates the symbol with a noise or pseudo-noise sequence predetermined by the control unit and known to the receiver. The transmitter according to any one of 44 to 58.   60. A transmitter as claimed in any one of claims 44 to 59, wherein the control unit is fluidly adapted to a selected symbol duration for the noise or pseudo-noise sequence to be used by the transmission unit.   61. Transmission according to any one of claims 44 to 60, wherein the control unit is adapted to operate the transmission unit for symbol radiation in such a way that the available channel bandwidth is fully used. Machine.   62. A transmitter as claimed in any one of claims 44 to 61, wherein the transmission unit is adapted to radiate symbols expanded in frequency.   63. A transmitter as claimed in any one of claims 44 to 62, wherein the transmission unit is adapted to emit symbols in the form of a chirp signal.   64. Transmitter according to any one of claims 44 to 63, wherein the transmission unit is adapted to superimpose a chirp signal intended for each receiver with respect to time.   65. The transmitter of claim 64, wherein the sum of instantaneously radiated transmit powers superimposed on each other in the chirp signal is equal to the maximum allowable transmit power in each channel.   66. Transmitter according to any one of claims 44 to 65, wherein the transmission unit is adapted to transmit symbols in the form of a CDMA sequence, in the form of an FDMA method or in the form of a TDMA method.   The control unit creates a control signal that determines the transmission unit to use one of a plurality of available access methods in communication with the receiver, depending on the current transmission state between the transmitter and the receiver 67. A transmitter as claimed in any one of claims 44 to 66 adapted to supply and supply.   68. The transmitter of claim 67, wherein the transmission unit is connected to a data memory containing transmission parameters or signal patterns of different symbol types.   69. A transmitter as claimed in any one of claims 44 to 68, having a discrete delay for signal expansion.   70. A transmitter as claimed in any one of claims 44 to 69, connected to a transmitter unit and adapted to generate an m-sequence for signal expansion.   71. Transmitter according to any one of claims 44 to 70, wherein the radiable signal is stored in a memory or can be read from a shift register structure.   Generate any signal to be radiated by execution of one or more algorithms executed in the form of a corresponding circuit or in the form of software, and presently radiated depending on the control signal from the control unit 72. A transmitter as claimed in any one of claims 44 to 71 adapted to generate a respective signal to be performed.   The transmission unit has a signal sequencer and an IQ modulator connected to its output, and the signal to be transmitted to the signal sequencer after creation of the signal, and then to the IQ modulator unit 73. A transmitter as claimed in any one of claims 44 to 72, adapted to pass and then directly convert the signal to a carrier band.   The transmitting unit is adapted to generate a signal to be transmitted digitally internally, and the transmitting unit has a digital-to-analog converter through which the internally generated digital signal passes before radiation Item 74. The transmitter according to any one of Items 44 to 73.   75. A transmitter as claimed in any one of claims 44 to 74 having a programmable transmitter configuration (software radio).   76. The transmitter of claim 75, wherein the transmitter configuration is fluidly variable.   77. A transmitter as claimed in any one of claims 44 to 76 comprising a channel estimation unit.   78. A transceiver configuration comprising a transmitter device and a receiver device, wherein the transmitter device has the transmitter characteristics of any one of claims 44-77.   The receiver device is adapted to receive information about the frequency band used in the transmission from the associated base station and direct the information to the transmitter device prior to transmission of the symbol to the base station. 79. The transceiver configuration of claim 78 in the form of a user's mobile terminal.   80. A transceiver configuration according to claim 79 in the form of a base transmitter station of a mobile radio network.   The receiver device is adapted to perform an RSSI measurement (radio signal strength indicator) of the power received from the second transceiver configuration via the communication channel and communicate a signal based on the measurement result to the transmitter device; 81. The transceiver configuration according to any one of claims 78-80, wherein the transmitter device is adapted to communicate a signal representative of the measurement result to the second transceiver configuration.   82. The transceiver configuration of claim 81, wherein the control unit of the transmitter device creates its control signal according to the RSSI measurement results obtained from the second transmitter receiver configuration. A receiver for performing the method according to any one of claims 1 to 43.

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