RU2085048C1 - Method for data transmission and reception over communication channel - Google Patents

Abstract

FIELD: digital data exchange using combination of various types of modulation (primarily amplitude-phase and amplitude-phase-frequency types). SUBSTANCE: method involves formation of layout of combination of signal points-vectors by vector summing of preset number of elementary signal points-vectors in various combinations, determination of consistence of each signal point-vector with definite data sign, determination of data signal pulse sequence followed by generation of respective data signals and concurrently, reference signal, their addition and transmission to communication channel; signal passed via this channel is distorted due to noise present there. Signal passed via communication channel is received, demodulated, processed considering separated reference signal, and its parameters are measured. Then signal is identified and corrected, if necessary. EFFECT: improved validity of signal identification after it has passed through communication channel. 5 dwg

Description

 The invention relates to the field of discrete information exchange using communication systems with amplitude, phase, frequency types of modulations used in various communication channels.

 A device is known that implements a method that, by the totality of actions, is closest to the proposed method and therefore is selected as a prototype.

 In the known method, an arrangement of a set of signal "point vectors" is formed, which are the ends of signal vectors located on a vector plane. As a vector plane, a two-coordinate plane is used in rectangular coordinates, in which the "point-vector" parameters are the projections of the vector on the X and Y axes. The signal point is one of the points of the adopted scheme that has individual coordinates on the vector plane and corresponds to a certain sign (code), necessary to transmit information.

 In the known method, the parameters of the sinusoidal signal necessary for generating the information signal and the duration of its transmission are determined, the information signals are generated, according to the parameters of the corresponding “point vectors”, the generated messages are transmitted to the communication channel, the transmitted information signals transmitted through the communication channel are received, determine the parameters of the received information signal, identify the received information signal, and convert it into a form convenient for the consumer.

 However, in the proposed method, the identification of the information signal that went through the communication channel and was distorted there is not high enough, because The decision on the identification of the signal occurs by the threshold method and in the coordinate system having phase and amplitude instability in time. (In data transmission systems using a signal constellation containing more than 2 signal “vector points”, the phase and amplitude stability of the coordinate system in which the signal constellation is identified on the receiving side is fundamentally necessary and affecting the accuracy of identification of received signals relative to the coordinate system on the transmitting side). The task of increasing the reliability of the restoration of the information signal that has passed through the communication channel in the proposed method is solved by introducing a reference signal that is associated with the dynamic range of information signals, is summed with the information signal and transmitted to the communication line, and after reception is extracted from the received signal and allows you to restore parameters of the transmitted signals due to the known relationship between the parameters in the reference and information signals. Secondly, the task of increasing the reliability of identification of received information signals is solved by linking the reference signal to the generated arrangement of the set of signal "point vectors" on the vector plane. The circuit itself is obtained in a "natural" way by means of vector summation of elementary signal "point vectors" in various combinations. (An elementary signal "point-vector" is one of the number of points initially selected to form a set of signal "point-vectors").

 The drawings show diagrams that help to understand the essence of the proposed method.

 In FIG. 1 shows a vector plane with 5 elementary signal “point vectors” plotted on it. On figa in a rectangular coordinate system, on figb in a polar coordinate system.

 Figure 2 is a diagram of a set of signal "point vectors" formed from 5 elementary.

 In FIG. 3, the sequence of formation of the information signal (elementary information signals, in figa, and information signals obtained by summing, in fig.3b, in the amplitude-time form and in the vector form).

In Fig.4, the sequence of formation of the total signal (information signal, the reference signal, the total signal). In amplitude-time form
5, parameter determination and identification of the received signal.

 The proposed method consists in sequentially performing the following actions.

 An arrangement of a set of signal "point vectors" is formed. To do this, preliminary consider the parameters of the circuit. The choice of the number of signal "point vectors" in the circuit depends on the number of information signs (symbols) necessary to ensure information transfer, on the other hand, the number of signal "point vectors" in the generated population depends on the number of initially selected elementary signal "point vectors" . In addition, considerations of optimal, in a given channel band, transmission speed and its reliability influence the choice of a circuit. For example, having 3 elementary signal "point-vectors", identical in amplitude and uniformly shifted in phase (on the vector plane in polar coordinates), we get 7 signal "point-vectors" (including zero-vector). Having 4 elementary “point vectors”, 9 signal “point vectors”, 5 elementary “point vectors” (see FIG. 1) 31 signal “point vectors” (see FIG. 2), etc.

 To form a circuit, for a given set (number) of input signs (symbols) necessary for transmitting information, the required number of elementary signal "point vectors" is set, knowing in advance which set of signal "point vectors" can be obtained by vector summing a known number of elementary signal "point-vectors" in various combinations and further, performing vector summation, get this combination, and therefore form the desired circuit.

Having formed the location scheme of the signal "point vectors", determine the dynamic range of the signal population on the vector plane. In FIG. 2 scheme, the dynamic range extends from 0 to r _max , and if the point with the coordinates "0" is not used, from r _min to r _max .

Next, the correspondence of each signal “point-vector” to a certain information sign (symbol) is determined. The input information signs are converted from the form used by the consumer to the form used in modulation and tightly connected with the parameters (geometric coordinates) corresponding to these signs of the signal "point-vectors". The frequency W _{and the} sinusoidal signal on the basis of which information signals are formed, and the duration of sending T _{and the} information signal are selected.

 (The information signal is a sinusoidal signal, formed in such a way that its parameters are tied to the geometric parameters of the corresponding "point vectors").

To form respective data signals _and S (cm. 3) is first formed elementary data signals, which represent the sinusoidal signal with frequency W _and the unit and associated signal parameters "vector points". Such parameters are the amplitude A and phase F in the polar system, or the coordinates X and Y in a rectangular system.

 Corresponding information signals are formed by summing those elementary information signals whose vectors, when summed up, form a point-vector corresponding to this information signal on the generated circuit. Such formation can be carried out using the memory of a reprogrammable memory device.

Further, in accordance with a certain sequence of input signs, information signals S are _{also formed} in parcel packets.

Parallel action on the formation of the information signal S _and form _of the reference signal S (see FIG. 4), by which the phase plane on the reception side is formed, and wherein the identification signal is carried out. The frequency of the generated reference signal is related to the selected frequency of the information signal by the ratio W = W _and / N, where N is a natural number.

The amplitude of the reference signal A _o is associated with the dynamic range of the signal constellation (with the upper boundary of the range of arrangement of the aggregate of signal points A = Kr _max , where r _{max is the} upper boundary of the range of the arrangement of the aggregate “point vectors”) and the magnitude of the information signal.

The generated information signal S _{and is} summed with the reference signal S _o , receive the total signal S _{(and + o)} (see figure 4) and modulate this signal in frequency carrier signal sent to the communication channel F _and [S _{(and + о)} ] The signal sent to the communication channel undergoes distortion due to interference.

The signal passed through the communication channel F _CR [S _{(and + o)} ] receive and conduct its frequency demodulation, highlighting the received total signal S _{CR (and + o)} .

The next step is to determine the parameters and duration of the received information signal. For this:
extracting from the total received signal S _{pr (and + o) the} received reference signal S _{pr (o)} ;
measure its amplitude A _{pr. o} compare it with a known magnitude of the amplitude of the reference signal A _o used in the formation of the total signal S _{(and + o)} , set the ratio of these amplitudes to the gain of the total received signal S _{pr (and + o)} ;
isolated from two signals S _{pr (and + o)} and S _{pr (o) the} received information signal S _{pr (and)} ;
in parallel with the previous action, the frequency of the reference signal is changed N times, while receiving a new frequency of the reference signal W _{n (o)} (this frequency is equal to the frequency of the information signal);
form using the signal W _{n (o)} two orthogonal signals (W _nx , W _ny ) for the correlation processing of the received information signal S _{pr (and)} . (Orthogonal signals have the same frequency and amplitude, but their phases are shifted 90 degrees);
the received information signal S _{pr (s) is} multiplied by orthogonal signals (W _nx , W _ny ), thereby obtaining (see FIG. 5) the correlation components of the received information signal X _{pr (s)} and Y _{pr (s)} , thereby obtaining parameters of the received information signal on a stabilized vector plane.

 The next step identifies the received information signal according to the arrangement of the set of signal points on the vector (phase) plane (see figure 5).

 Then, if necessary, the received information signals are corrected based on the parameters of the received reference signal.

 In conclusion, the identified signal is converted into a form convenient for the consumer.

Claims (1)

The method of transmitting and receiving information over the communication channel, which consists in forming a layout of the set of signal points-vectors on the vector plane, choosing the parameters of the sinusoidal signal necessary for generating the information signal, and the duration of its sending, forming the sending of transmitted information signals according to the parameters of the corresponding signal points-vectors and the duration of the package, transmit the package of information signals to the communication channel, receive the package of information signals, p transmitted through the communication channel, determine the parameters of the received information signal, identify the received information signal, convert the identified signal into a form convenient for the consumer, characterized in that when forming the arrangement of the set of signal vector points, the number and location of elementary signal vector points on the vector planes and get a set of signal point vectors by vector summation of elementary signal point vectors in various combinations ning, determine the dynamic range of information signals on the vector plane from the totality of the received signal points-vectors, when generating packages of information signals, elementary information signals are first formed that correspond to elementary point vectors in their parameters, and information signals are formed by summing elementary information signals in various combinations form a reference signal, linking its parameters with the value of the dynamic range of the information signal s and the frequency information signal, setting its phase is zero with respect to the zero phase vector plane, while the frequency is selected according to the formula W _{o p} W _v / N, where N a natural number, are summed data signal with a reference to obtain the information transmitted S _n signal _{(u + o)} receiving the transmitted information signal, allocate the received summary information signal S _{n p (u + v),} in determining the parameters is recovered from the sum signal of the received signal S _{n p (u + v)} the received reference signal S _{n p (n),} measured its amplitude, setting According to its value, the signal gain S _{p p (and + o)} , the information signal S _{p p ( s)} is extracted from the two signals S _{p p (and + o)} and S _{p p (o )} and is also simultaneously changed N times the frequency of the reference signal S _{p p (o)} , receiving a new reference signal S _{p p . n (o)} , from which two quadrature signals are then obtained and the correlation processing of the received information signal is carried out and the received signal is corrected by which the identification is carried out.

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