SU1566494A1 - Radio communication system with single-sideband angle modulation - Google Patents

Abstract

A single-band angular modulation radio communication system comprising a message source, a power amplifier on the transmitting side, and a linear unit, an adder, a demodulator on the receiving side, and the output of the adder is connected to the input of the demodulator, which is non-linear distortions for large modulation indexes, a single-quadrature signal forming unit of a single-band signal, a derived message sign shaping unit, an adder, the first output of the message source connected to the input unit of the formation of a single quadrature component of a single-pole signal, the output of which is connected to the first input of the adder, the second output of the message source is connected to the second input of the adder, the output of which is connected to the power amplifier, on the receiving side entered a filter unit of a single quadrature component, the selection unit derivative symbol, differentiation unit, another quadrature component forming unit, first and second mixers, another quadrature component forming unit, fa a rotator, the first output of the linear unit connected to the first inputs of the filtering unit of one quadrature component, the first mixer and the input of the phase shifter, the second output of the linear unit connected to the second input of the filtering unit of one quadrature component, the output of which is connected to the second input of the first mixer, as well as inputs units of differentiation and formation of the module of another quadrature component, the third output of the linear unit is connected to the input of the block for the selection of the sign of the derivative, the output of which is connected to To the left input of the forming unit is another quadrature component, the second input of which is connected to the output of the forming unit module of another quadrature component, and the third input of the forming unit of another quadrature component is connected to the output of the differentiation unit, the output of the forming unit of another quadrature component is connected to the first input of the second mixer, the second input of which is connected to the output of the phase shifter, the output of the second mixer is connected to the first input of the adder, the second input of which is connected to the output p first mixer

Description

The invention relates to radio and can be used in the transmission of signals with angular modulation with large indices,

The purpose of the invention is to reduce the nonlinear distortion of ggry large modulation indices.

FIG. Figure 1 shows the electrical circuit of the proposed system, the transmitting part; figure 2 - the receiving part.

The radio communication system with a single band angular modulation contains a source of 1 message, a power amplifier 2, a block 3 forming a single quadrature component of a single band signal, a block 4 forming the sign of a derived message, an adder 5, a linear block 6, an adder 7, a demodulator 8, filtering unit 9 of one quadrature component, derivative mark extracting unit 10, differentiation unit 11, another forming quadrate 12, the first 13 and second 14 mixers, another module forming unit 15 s and a phase shifter 16,

The system works as follows

The signal from source 1 is fed to the input of block 3, where a single-band signal and carrier are formed, and the single-band signal contains only the sinus (or cosine) components of the signal, in addition, the original information is fed to the input of block 4, where shaping and modulation is performed an additional carrier signal of the derivative symbol. The signals from the outputs of blocks 3 and 4 are fed to the inputs of the adder 5 and further to the amplifier 2, At the receiving side

with

Q

50

Q 5

thirty

35

The non-carrier signal from the output of the linear unit 6 enters the mixer 13 and the phase shifter 16, the second and third outputs of the linear unit 6 receive the carrier signal and the filtered sine or cosine components of the signal to the input of the unit 12, where the low-frequency sinus (or cosine) components are extracted signals. From the fourth output of the linear block 6, the signal about the sign of the derivative arrives at block 10, where it produces demodulation and detection of the sign of the derivative. The signal from block 9 is fed to a mixer 14 and a differentiation unit, where the derivative of the received signal is formed. From the output of block 11, the sign of the derivative of the received signal is fed to the input of block 12, the input of which receives the sign of the derivative and the transmitted message from block 9. The third input of block 12 receives a module, a cosine (or sine) component, formed in block 15 of the signal received from the output of block 9; block 12 compares the signs of the derivatives of the information signal and those formed by block 1 1 and assigns the sign to the module of the cosine (or sine) component according to the following rule: if the signs of the derivative are are different, the + sign is assigned to the module, if the derivative signs are different, then the sign is assigned to the module. Then the signal from the output of block 12 goes to mixer 14, to the second input of which a signal arrives with a phase shift of 90.

From the outputs of mixers 13 and 14, the signals are fed to an adder 7, where a two-band signal is formed, which is demodulated in demodulator 8,

1

Claims (1)

RADIO COMMUNICATION SYSTEM WITH SINGLE-BAND ANGULAR MODULATION, containing the message source, power amplifier on the transmitting side, and a linear block, adder, demodulator on the receiving side, the adder output connected to the demodulator input, characterized in that, in order to reduce non-linear distortion at large indices modulations, a unit for generating one quadrature component of a single-cavity signal, a unit for generating a sign of a derivative message, an adder, the first output of the message source being introduced on the transmitting side the first is connected to the input of the unit for generating one quadrature component of the single-band signal, the output of which is connected to the first input of the adder, the second output of the message source is connected to the second input of the adder, the output of which is connected to the power amplifier, "and the filter side of the filter for one quadrature component, the allocation unit derivative sign, differentiation unit, another quadrature component formation unit, first and second mixers, module formation unit, another quadrature component, f a rotator, wherein the first output of the linear block is connected to the first inputs of the filtering block of one quadrature component, the first mixer and the input of the phase shifter, the second output of the linear block is connected to the second input of the filtering block of one quadrature component, the output of which is connected to the second input of the first mixer, as well as the inputs of the blocks differentiation and formation of another quadra- module. component, the third output of the linear block is connected to the input of the derivative sign extraction unit, the output of which is connected to the first input of the formation unit of another quadrature component, the second input of which is connected to the output of the module formation unit of another quadrature component, and the third input of the formation unit of another quadrature component is connected with the output of the differentiation block, the output of the block forming another quadrature component is connected to the first input of the second mixer, the second input of which union of a yield of a phase shifter, a second mixer output is connected to the first input of the adder, the second input of which is connected to the output of the first mixer. Joint venture