Radiofrequency communication device using a TORP signal

Abstract

Radiofrequency communication device comprising at least one TORP signal generation circuit, the TORP signal corresponding to oscillations trains periodically repeated at a frequency F.sub.PRP for which the oscillation frequency is F.sub.OL>F.sub.PRP and for which each oscillations train lasts for a duration of less than 1/F.sub.PRP, and at least one multiplier circuit for which an input is coupled to an output of said at least one TORP signal generation circuit such that it is capable of multiplying the TORP signal with a baseband signal comprising at least one of information intended to be transmitted by the radiofrequency communication device and a radiofrequency signal intended to be received by the radiofrequency communication device.

Claims

1. A radiofrequency communication device comprising: at least one TORP signal generation circuit, a TORP signal generated by the at least one TORP signal generation circuit corresponding to oscillations trains periodically repeated at a frequency FPRP for which the oscillation frequency is FOL>FPRP and for which each oscillations train lasts for a duration of less than 1/FPRP, the TORP signal having a zero value between the oscillation trains, and at least one multiplier circuit including an input coupled to an output of said at least one TORP signal generation circuit applying the TORP signal on said input of the at least one multiplier circuit such that the multiplier circuit is configured to multiply the TORP signal with at least one of a baseband signal comprising information intended to be transmitted by the radiofrequency communication device and a radiofrequency signal intended to be received by the radiofrequency communication device.

2. The device according to claim 1, wherein said at least one multiplier circuit corresponds to a first multiplier circuit configured to multiply the TORP signal with the baseband signal and to a second multiplier circuit configured to multiply the TORP signal with the radiofrequency signal.

3. The device according to claim 2, wherein said at least one TORP signal generation circuit corresponds to a first TORP signal generation circuit for which one output is coupled to an input of the first multiplier circuit and to a second TORP signal generation circuit for which one output is coupled to an input of the second multiplier circuit.

4. The device according to claim 1, further comprising: at least two switches configured to couple the output of said at least one TORP signal generation circuit with the input of at least one of the multiplier circuits through direct interconnection or via a first circuitry configured to use the TORP signal to generate a periodic signal for which a frequency spectrum comprises a principal line corresponding to one of the lines in the TORP signal spectrum and configured to act as a passband filter applied to the TORP signal and configured to reject lines other than the principal line of said periodic signal from the frequency spectrum of said periodic signal.

5. The device according to claim 4, wherein the first circuitry configured to generate said periodic signal comprises at least one injection locked oscillator configured to receive the TORP signal as input and to be at least periodically locked to a frequency at which the principal line of said periodic signal is located.

6. The device according to claim 1, wherein said at least one TORP signal generation circuit comprises at least: an oscillator configured to generate a periodic signal with frequency FOL, and a second circuitry that can be controlled by a periodic signal with frequency FPRP, and that is connected to an electrical power supply input of the oscillator such that the second circuitry generates a non-zero power supply voltage of the oscillator only during part of each period 1/FPRP, or that is connected to an output of the oscillator such that the second circuitry cuts off an electrical connection between the output of oscillator and an output of the TORP signal generation circuit during only part of each period 1/FPRP.

7. The device according to claim 6, further comprising: at least one switch configured to output either the periodic signal with frequency FPRP in a first configuration, or the baseband signal in a second configuration, onto a control input of the second circuitry of said at least one TORP signal generation circuit, and at least one switch configured to output either the baseband signal in the first configuration, or a constant amplitude signal corresponding to the amplitude of a bit with value in the second configuration, onto an input of the multiplier circuit.

8. The device according to claim 6, further comprising: at least one phase locked loop configured to output the periodic signal with frequency FPRP.

9. The device according to claim 1, wherein the output of said at least one TORP generation circuit is directly coupled to the input of said at least one multiplier circuit.

10. The device according to claim 1, wherein the TORP signal has the zero value during an entirety of an interval between the oscillation trains.

11. A radiofrequency communication method, comprising: generating, in at least one TORP generation circuit, at least one TORP signal corresponding to oscillations trains periodically repeated at a frequency FPRP of which the oscillations are at frequency FOL>FPRP and for which each oscillations train has a duration of less than 1/FPRP, the at least one TORP signal having a zero value between the oscillation trains; applying the TORP signal to an input of at least one multiplier circuit; and multiplying, in the at least one multiplier circuit, the at least one TORP signal with at least one of a baseband signal comprising information to be transmitted and a received radiofrequency signal.

12. The method according to claim 11, further comprising: implementing at least one of a first multiplication between a first TORP signal and the baseband signal, and a second multiplication between a second TORP signal and the received radiofrequency signal.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) This invention will be better understood after reading the description of example embodiments given purely for guidance and in no way limitative with reference to the appended drawings in which:

(2) FIG. 1 diagrammatically shows a radiofrequency communication device according to a first embodiment;

(3) FIGS. 2 and 3 show TORP signals according to two different embodiments in the time and frequency domains used within a radiofrequency communication device;

(4) FIGS. 4 and 5 show signal frequency spectra during a signal transmission through the radiofrequency communication device;

(5) FIGS. 6 to 8 show signal frequency spectra during a signal reception through the radiofrequency communication device;

(6) FIGS. 9 to 11 diagrammatically show a radiofrequency communication device according to a second, third and fourth embodiment respectively;

(7) FIG. 12 diagrammatically shows an example embodiment of means of generating a non-coherent TORP signal.

(8) Identical, similar or equivalent parts of the different figures described below have the same numeric reference to facilitate comparison between the different figures.

(9) The different parts shown in the figures are not necessarily all shown at the same scale, to make these figures more easily legible.

(10) The different possibilities (variants and embodiments) shall be understood as not being exclusive of each other and may be combined with each other.

DETAILED PRESENTATION OF PARTICULAR EMBODIMENTS

(11) Refer firstly to FIG. 1 that diagrammatically shows a first embodiment of a radiofrequency communication device 100.

(12) The device 100 comprises a part 102 symbolically delimited by dashed lines and that is used to make transmission of signals in the RF domain. This part 102 of the device 100 comprises a first baseband signal processing circuit 104 receiving input consisting of information to be transmitted, and outputting a baseband signal to be transmitted, called the BB.sub.TX signal. The part 102 also comprises a circuit 106 forming means of generating a TORP type signal, in other words a signal forming Periodically Repeated Oscillations Trains, and a first multiplier circuit 108 capable of multiplying the BB.sub.TX signal and the TORP signal in the time domain, this multiplication in the time domain corresponding to a convolution product between the TORP and BB.sub.TX signals in the frequency domain, so that the BB.sub.TX signal can be transposed to the required carrier frequency (defined through the TORP signal), outputting an RF signal called the RF.sub.TX signal at the output. The part 102 also comprises a power amplifier 110 and a transmission antenna 112 to transmit the RF.sub.TX signal in an RF propagation channel.

(13) The device 100 also comprises a part 114 symbolically delimited by dashed lines and capable of receiving an RF signal from the RF propagation channel. This part 114 of the device 100 comprises a reception antenna 116 and a low noise amplifier 118 outputting an RF.sub.RX signal corresponding to the amplified received RF signal. The part 114 also comprises a second multiplier circuit 120 multiplying the RF.sub.TX signal and the TORP signal outputted from the circuit 106 in the time domain, which corresponds to a convolution product between the RF.sub.RX and TORP signals in the frequency domain, thus transposing the RF.sub.RX signal into baseband forming a signal called the BB.sub.RX signal. The part 114 also comprises a second baseband processing circuit 122 receiving the BB.sub.RX signal as an input, and outputting information transmitted in the received RF signal.

(14) In this first embodiment, the same TORP signal is used both for transmission and for reception. Thus, the circuit 106 that generates the TORP signal forms part of the part 102 comprising elements performing signal transmission and also of the part 114 comprising elements performing signal reception.

(15) Unlike transmission and reception devices according to prior art in which one or several sinusoidal signals are generated by one or several local oscillators and are multiplied either by the baseband signal in transmission or by the RF signal in reception, the signal used for frequency transposition of the baseband signal in transmission and of the RF signal in reception corresponds to a TORP type signal for which the characteristics are described in detail below.

(16) The TORP signal used for transmission and for reception of signals may or may not be coherent, depending on the elements forming the circuit 106 generating it.

(17) A coherent TORP signal is defined in the time domain as the result of a convolution between a first signal called g.sub.1(t) corresponding to a frequency sine F.sub.OL windowed in width /F.sub.PRP (where 0<<1) and a second signal h.sub.1(t) corresponding to a Dirac comb with period 1/F.sub.PRP:

(18) $\begin{array}{cc}{g}_1\left(t\right)=\sin \left(2.Math..Math.F_{\mathrm{OL}}.Math.t\right).Math.\left(t\frac{F_{\mathrm{PRP}}}{}\right)& \left(1\right)\\ h_1\left(t\right)=\underset{k=-}{\overset{+}{.Math.}}\left(t-\frac{k}{F_{\mathrm{PRP}}}\right)& \left(2\right)\end{array}$

(19) The signal resulting from this convolution is a coherent TORP signal called torp.sub.1(t), corresponding to trains or sets of frequency oscillations F.sub.OL repeated periodically at frequency F.sub.PRP, and that is defined by the following relation:

(20) $\begin{array}{cc}{\mathrm{torp}}_1\left(t\right)=g_1\left(t\right)*h_1\left(t\right)=\left[\sin \left(2.Math..Math.F_{\mathrm{OL}}.Math.t\right).Math.\left(t\frac{F_{\mathrm{PRP}}}{}\right)\right]*\underset{k=-}{\overset{+}{.Math.}}\left(t-\frac{k}{F_{\mathrm{PRP}}}\right)& \left(3\right)\end{array}$

(21) The frequency of coherent TORP signal oscillations is equal to F.sub.OL. The duration of each oscillations train is equal to /F.sub.PRP, these oscillations trains being repeated every 1/F.sub.PRP, in other words periodically repeated at the frequency F.sub.PRP.

(22) Such a TORP signal is qualified as being coherent because its oscillations trains have the property of being coherent in phase, in other words the phase at the start of each oscillations train every 1/F.sub.PRP, is always the same.

(23) In the frequency domain, the coherent TORP signal corresponds to the multiplication between a cardinal sine centred on F.sub.OL called G.sub.1(f) (corresponding to the frequency spectrum of signal g.sub.1(t)) and a Dirac comb with period F.sub.PRP called H.sub.1(f) (corresponding to the frequency spectrum of signal h.sub.1(t)):

(24) $\begin{array}{cc}{G}_1\left(f\right)=\frac{1}{2j}\left[\left(f-F_{\mathrm{OL}}\right)-\left(f+F_{\mathrm{OL}}\right)\right]*\frac{}{F_{\mathrm{PRP}}}.Math.\sin c\left(.Math.f.Math.\frac{}{F_{\mathrm{PRP}}}\right)& \left(4\right)\\ H_1\left(f\right)=F_{\mathrm{PRP}}.Math.\underset{k=-}{\overset{+}{.Math.}}\left(f-k.Math.F_{\mathrm{PRP}}\right)& \left(5\right)\end{array}$

(25) The result of this multiplication, called TORP.sub.1(f) and corresponding to the frequency spectrum of signal torp.sub.1(t), is a discrete spectrum with lines at multiple frequencies of F.sub.PRP and the envelope of which is a cardinal sine:

(26) $\begin{array}{cc}{.Math.{\mathrm{TORP}}_1\left(f\right).Math.}_{f>0}=G_1\left(f\right).Math.H_1\left(f\right){.Math.{\mathrm{TORP}}_1\left(f\right).Math.}_{f>0}=\left[\frac{1}{2}\left(f-F_{\mathrm{OL}}\right)*\frac{}{F_{\mathrm{PRP}}}.Math.\sin c\left(.Math.f.Math.\frac{}{F_{\mathrm{PRP}}}\right)\right].Math.F_{\mathrm{PRP}}.Math.\underset{k=0}{\overset{+}{.Math.}}\left(f-k.Math.F_{\mathrm{PRP}}\right)& \left(6\right)\end{array}$

(27) The different signals described above for the coherent TORP signals are shown in FIG. 2. In particular, this figure shows that the lines in the spectrum corresponding to the TORP.sub.1(f) signal are located at multiple frequencies of F.sub.PRP and the amplitudes of these lines are defined by the envelope signal corresponding to G.sub.1(f). The frequency F.sub.OL is preferably chosen so that it is close to or equal to one of the multiple frequencies of F.sub.PRP so that one of the lines of signal TORP.sub.1(f) is located at the maximum amplitude or close to the maximum of the envelope and therefore that the amplitude of this line is equal to this maximum. In the example shown in FIG. 2, this frequency F.sub.OL shown in dashed lines on signal TORP.sub.1(f) is not equal to a multiple of F.sub.PRP and therefore none of the lines in signal TORP.sub.1(f) is at an amplitude equal to the maximum amplitude of the envelope signal.

(28) Such a coherent TORP signal is for example obtained by using a circuit 106 like that shown in FIG. 9 (the device 100 shown in FIG. 9 will be described in detail later). In this FIG. 9, the circuit 106 comprises a PLL, or a frequency synthesis 124 that can lock and stabilise the frequency of a periodic signal with frequency F.sub.PRP, for example a sinusoidal signal outputted by an oscillator not shown in FIG. 9 and with a frequency of more than about 1 GHz, and can output this frequency stabilised periodic signal. As a variant, this PLL or frequency synthesis 124 may be replaced by any device or structure capable of directly providing a periodic signal with frequency F.sub.PRP stable in frequency such as a resonator device. The circuit 106 also comprises a VCO (voltage controlled oscillator) 126 capable of outputting a periodic signal with frequency F.sub.OL, for example less than or equal to 10 GHz or equal to several tens of GHz, and controlled electrical power supply means 128 electrically powering the oscillator 126 and that are controlled by the signal outputted by the PLL or frequency synthesis 124. These means 128 comprise for example a switch located between an electrical power supply input of the oscillator 126 and an electrical power supply, and that can be controlled by the periodic signal outputted by the PLL or frequency synthesis 124 or as in the example in FIG. 9, a controlled current source functioning either as a switch periodically interrupting the electrical power supply of the oscillator 126 at the frequency of the signal outputted by the PLL or frequency synthesis 124. This controlled current source may correspond to a MOS transistor, the signal outputted by the PLL or frequency synthesis 124 being applied to the gate of this transistor. A control voltage is also applied to the input of the oscillator 126 so as to control the frequency value of the signal outputted by the oscillator 126.

(29) A non-coherent TORP signal is defined in the time domain as the result of a multiplication between a first signal called g.sub.2(t) corresponding to a sine curve with frequency F.sub.OL and a second signal h.sub.2(t) corresponding to a square signal with period 1/F.sub.PRP and cyclic ratio :

(30) $\begin{array}{cc}{g}_2\left(t\right)=\sin \left(2.Math..Math.F_{\mathrm{OL}}.Math.t\right)& \left(7\right)\\ h_2\left(t\right)=\underset{k=-}{\overset{+}{.Math.}}\left(t-\frac{k}{F_{\mathrm{PRP}}}\right)*\left(t\frac{F_{\mathrm{PRP}}}{}\right)& \left(8\right)\end{array}$

(31) The signal resulting from this multiplication is a non-coherent TORP signal called torp.sub.2(t), corresponding to oscillations trains with frequency F.sub.OL periodically repeated at frequency F.sub.PRP and that is defined by the following equation:

(32) $\begin{array}{cc}{\mathrm{torp}}_2\left(t\right)=g_2\left(t\right).Math.h_2\left(t\right)=\sin \left(2.Math..Math.F_{\mathrm{OL}}.Math.t\right).Math.\left[\underset{k=-}{\overset{+}{.Math.}}\left(t-\frac{k}{F_{\mathrm{PRP}}}\right)*\left(t\frac{F_{\mathrm{PRP}}}{}\right)\right]& \left(9\right)\end{array}$

(33) The frequency of oscillations of the non-coherent TORP signal is equal F.sub.OL. The duration of each oscillations train is equal to /F.sub.PRP, these oscillations trains being repeated every 1/F.sub.PRP, in other words they are periodically repeated at frequency F.sub.PRP.

(34) Unlike the previous coherent TORP signal, oscillations trains of the non-coherent TORP signal are not necessarily coherent in phase, in other words the phase at the start up of each oscillations train, in other words every 1/F.sub.PRP, may be different.

(35) In the frequency domain, the non-coherent TORP signal corresponds to the convolution between a Dirac at frequency F.sub.OL, called G.sub.2(f) and corresponding to the frequency spectrum of g.sub.2(t), and a cardinal sine discretised at multiple frequencies of F.sub.PRP called H.sub.2(f) and corresponding to the frequency spectrum of h.sub.2(t):

(36) $\begin{array}{cc}{G}_2\left(f\right)=\frac{1}{2j}\left[\left(f-F_{\mathrm{OL}}\right)-\left(f+F_{\mathrm{OL}}\right)\right]& \left(10\right)\\ H_2\left(f\right)=F_{\mathrm{PRP}}.Math.\underset{k=-}{\overset{+}{.Math.}}\left(f-k.Math.F_{\mathrm{PRP}}\right).Math.\frac{}{F_{\mathrm{PRP}}}.Math.\sin c\left(.Math.f.Math.\frac{}{F_{\mathrm{PRP}}}\right)& \left(11\right)\end{array}$

(37) The result of this convolution called TORP.sub.2(f) and corresponding to the frequency spectrum of signal torp.sub.2(t) is a translation of the discretised cardinal sine H.sub.2(f) around the frequency F.sub.OL:

(38) $\begin{array}{cc}{.Math.{\mathrm{TORP}}_2\left(f\right).Math.}_{f>0}=G_2\left(f\right)*H_2\left(f\right)=H_2\left(f-F_{\mathrm{OL}}\right){.Math.{\mathrm{TORP}}_2\left(f\right).Math.}_{f>0}=F_{\mathrm{PRP}}.Math.\underset{k=0}{\overset{+}{.Math.}}\left(f-F_{\mathrm{OL}}-k.Math.F_{\mathrm{PRP}}\right).Math.\frac{}{F_{\mathrm{PRP}}}.Math.\sin c\left(.Math.\left(f-F_{\mathrm{OL}}\right).Math.\frac{}{F_{\mathrm{PRP}}}\right)& \left(12\right)\end{array}$

(39) The different signals described above for the non-coherent TORP signal are shown in FIG. 3. In particular, this figure shows that the frequency of the central line of the discretised cardinal sine in signal TORP.sub.2(f) is always equal to F.sub.OL.

(40) Such a non-coherent TORP signal is obtained for example from a circuit 106 like that shown in FIG. 12. In this circuit 106, the oscillator 126 is powered continuously and outputs a sinusoidal signal at frequency F.sub.OL. This sinusoidal signal is sent to the input of a switch 144 controlled by the periodic signal with frequency F.sub.PRP outputted by the PLL or frequency synthesis 124. The switch 144 is in the closed position periodically (period 1/F.sub.PRP) for a duration corresponding to part of the period 1/F.sub.PRP and equal to /F.sub.PRP, and during which an oscillations train is outputted.

(41) In the transmission part 102 of the device 100, the baseband signal BB.sub.TX is multiplied (in the time domain) with the TORP signal by the first multiplier circuit 108 (FIG. 1). The spectrum of the RF.sub.TX signal corresponding to the result of this multiplication (that corresponds to a convolution in the frequency domain) is different depending on the width of the spectrum of the BB.sub.TX signal compared with the frequency F.sub.PRP corresponding to the frequency at which the lines of the TORP signal are repeated.

(42) FIG. 4 shows the case in which the width of the BB.sub.TX signal spectrum is less than or equal to the frequency F.sub.PRP, in other words the case in which the maximum frequency F.sub.max of the BB.sub.TX signal is such that F.sub.maxF.sub.PRP/2. In this case, it can be seen that the RF.sub.TX signal spectrum obtained is composed of several spectral bands centred around frequencies of the lines of the TORP signal that are at a spacing from each other equal to F.sub.PRP. Since the width of each of these spectral bands is equal to the width of the BB.sub.TX signal spectrum that is less than or equal to F.sub.PRP, there is no overlap between the different spectral bands of the RF.sub.TX signal.

(43) FIG. 5 shows the case in which the width of the BB.sub.TX signal spectrum is higher than the frequency F.sub.PRP, in other words the case in which the maximum frequency F.sub.max of the BB.sub.TX signal is such that F.sub.max>F.sub.PRP/2. In this case, it can be seen that the RF.sub.TX (signal spectrum obtained is formed from several spectral bands centred around the frequencies of the lines of the TORP signal that are at a spacing equal to F.sub.PRP from each other. Since the width of each of these spectral bands is equal to the width of the BB.sub.TX signal spectrum that is higher than F.sub.PRP, there is an overlap between adjacent spectral bands of the RF.sub.TX (signal.

(44) Similarly, the BB.sub.RX signal spectrum corresponding to the result of the multiplication of the TORP signal and the RF.sub.RX signal in the time domain is different depending on the width of the RF.sub.RX signal frequency spectrum in comparison with the frequency F.sub.PRP and on the spectrum shape of the RF.sub.RX signal. Since the convolution product is distributive on addition, this convolution in the frequency domain may be considered as being done separately for each line in the TORP signal spectrum with the RF.sub.RX signal, the frequency spectrum of the signal obtained corresponding to the sum of these convolutions. Therefore, the resulting BB.sub.RX signal spectrum corresponds to the sum of the convolution products between each of the lines of the TORP signal and the RF.sub.RX signal spectrum.

(45) FIG. 6 illustrates the case of an RF.sub.RX signal for which the frequency spectrum occupies a single spectral band with a width less than or equal to the frequency F.sub.PRP, for an RF.sub.RX signal corresponding to a signal transmitted without the use of a TORP signal (because this RF.sub.RX signal comprises only one spectral band unlike the RF.sub.TX (signals previously described with reference to FIGS. 4 and 5). In this case, by using a TORP signal for which the spectrum comprises one line (preferably the central line with a larger amplitude) located at the central frequency of the RF.sub.RX signal, the BB.sub.RX signal contains the content of the RF.sub.RX received signal around all multiples of F.sub.PRP defined by the lines of the TORP signal. Therefore the spectrum of the obtained BB.sub.RX signal is formed from several spectral bands that are spaced from each other at a spacing equal to F.sub.PRP, each of which contains the content of the RF.sub.RX signal. The BB.sub.RX signal spectrum corresponds to the sum of the contributions of the convolution products of each line of the TORP signal with the RF.sub.RX signal, due to the distributivity of the convolution product relative to the addition. Each of these contributions forms one of the spectral bands of the BB.sub.RX signal. The right part of FIG. 6 individually shows each of these spectral bands, the numbers indicated at the side of these bands corresponding to the numbers of the lines in the TORP signal spectrum shown on the left part of FIG. 6. Because the width of each of these spectral bands is equal to the width of the RF.sub.RX signal spectrum that is less than or equal to F.sub.PRP, there is no overlap between the different spectral bands of the BB.sub.RX signal. Filtering, for example implemented by the second baseband processing circuit 122 and represented symbolically by dashed lines on the BB.sub.RX signal in FIG. 6, means that only the spectral band located around the zero frequency (and that corresponds to the highest amplitude spectral band when the central line with the highest amplitude of the TORP signal is at a frequency equal to the central frequency of the RF.sub.RX signal) is retrieved, which is sufficient to obtain the transmitted information.

(46) FIG. 7 shows the case of an RF.sub.RX signal for which the frequency spectrum occupies a single spectral band wider than the frequency F.sub.PRP, for an RF.sub.RX signal corresponding to a signal transmitted without the use of a TORP signal. In the example shown in FIG. 7, the spectrum of the RF.sub.RX signal occupies a spectral band the width of which is equal to several times F.sub.PRP, and therefore covers several lines in the TORP signal spectrum. In this case, the sum of the convolution products of the different lines in the TORP signal spectrum and this RF.sub.RX signal (shown individually on the right part of FIG. 7) gives a complex result with folding around the zero frequency around which the BB.sub.RX signal spectrum is centred. Signal processing more complex than a simple filtering is necessary in this case to obtain initial information transmitted in the RF.sub.RX signal, in the BB.sub.RX signal.

(47) FIG. 8 represents the case of an RF.sub.RX signal for which the frequency spectrum occupies several spectral bands each with a width less than or equal to frequency F.sub.PRP, the RF.sub.RX signal corresponding to a signal transmitted using a TORP signal. For example, this RF.sub.RX signal corresponds to the RF.sub.TX (signal previously described in relation with FIG. 4. In this case, the convolution of the RF.sub.RX signal spectrum with each line of the TORP signal spectrum contributes to translating the received spectrum towards the zero frequency and the contributions of each convolution are additive (this addition is shown in FIG. 8 symbolically by the stack of spectral bands on the BB.sub.RX signal spectrum). This addition can be used to obtain spectral bands and particularly the spectral band centred around the zero frequency, with a higher amplitude than in the case previously described with reference to FIG. 6. A better signal-to-noise ratio is also obtained given that the noise of the contributions added on the same spectral band is averaged instead of being added. Filtering, for example used by the second baseband processing circuit 122 and symbolically shown in dashed lines on the BB.sub.RX signal in FIG. 8, makes it possible to retrieve only the spectral band located around the zero frequency that is sufficient to obtain the initial transmitted information.

(48) It is also possible to receive an RF.sub.RX signal for which the frequency spectrum comprises several spectral bands overlapping each other, like the RF.sub.TX signal previously described with reference to FIG. 5. In this case, a BB.sub.RX signal is obtained for which the spectrum is more complex than that previously described with reference to FIG. 8. In this case, a more complex signal processing than a simple filtering is necessary to restore the initial information transmitted in the RF.sub.RX signal, in the BB.sub.RX signal.

(49) The circuit 106 of the device 100 may correspond to the circuit 106 previously described with reference to FIG. 9 and used to generate a coherent TORP signal, or may correspond to the circuit 106 previously described with reference to FIG. 12 and used to generate a non-coherent TORP signal.

(50) In one variant of the first embodiment described above, the circuit 106 outputting the TORP signal may be connected only to the transmission part 102 or to the reception part 114 of the device 100. The TORP signal in this case is used only with the part 102 or the part 114 of the device 100. The other part that does not use the TORP signal to make the frequency transposition of the baseband BB.sub.TX signal or the RF.sub.RX signal may use a periodic signal such as a sinusoidal signal for the multiplication to achieve this frequency transposition. According to another variant, the device 100 may correspond to a signal transmission device only comprising the part 102 or it may correspond to a signal reception device only comprising the part 104.

(51) According to another variant embodiment, the device 100 may comprise two different circuits 106 each coupled to one of the parts 102 and 114. Thus, different TORP signals may be used to perform signal transmission and signal reception.

(52) FIG. 9 shows a radiofrequency communication device 100 according to a second embodiment.

(53) As in the first embodiment, the transmission part 102 of the device 100 comprises a first baseband processing circuit 104, the circuit 106 generating the TORP signal, the first multiplier circuit 108, the power amplifier 110 and the transmission antenna 112. As a variant, the circuit 106 shown in FIG. 9 may be replaced by the circuit described previously with reference to FIG. 12 generating a non-coherent TORP signal.

(54) The transmission part 102 of the device 100 also comprises a first switch 130 comprising one input and two outputs (one marked as reference A and the other marked as reference B in FIG. 9), and a second switch 132 comprising two inputs (one marked with reference A and the other marked with reference B) and one output. The two switches 130 and 132 are controlled by the same control signal in order to obtain two configurations.

(55) In a first configuration (corresponding to the case shown in FIG. 9), the input of the first switch 130 is connected to the first output referenced A of the first switch 130, and the first input referenced A of the second switch 132 is connected to the output of the second switch 132. Since the output of the circuit 106 is connected to the input of the first switch 130 and the output of the second switch 132 is connected to the input of the first multiplier circuit 108 and the first output A of the first switch 130 is electrically connected to the first input A of the second switch 132 through a simple electrical connection 134 for example composed of a conducting wire or track, in this first configuration the TORP signal outputted by the circuit 106 is applied to the input of the multiplier circuit 108. In this first configuration, operation of the transmission part 102 of the device 100 according to the second embodiment is similar to that described previously for the device 100 according to the first embodiment.

(56) In a second configuration, the input of the first switch 130 is connected to the second output referenced B of the first switch 130, and the second input referenced B of the second switch 132 is connected to the output of the second switch 132. The second output of the first switch 130 is connected to the input of an injection locked oscillator (ILO) circuit 136 that generates a periodic signal from the TORP signal, for which the frequency spectrum comprises a principal line corresponding to one of the lines in the TORP signal spectrum and acts as a passband filter applied to the TORP signal that rejects lines other than the principal line of said periodic signal, from the frequency spectrum of said periodic signal.

(57) Thus, in this second configuration, the ILO 136 can retrieve one of the frequencies of the TORP signal and therefore can output a periodic signal to the input of the first multiplier circuit 108, for example a sinusoidal signal, for which the spectrum has a principal line for which the amplitude has a value very much higher than the amplitudes of adjacent lines if there are any (the presence of these adjacent lines being due to the fact that the ILO 136 does not reject these adjacent lines perfectly). In this second configuration, operation of the transmission part 102 of the device 100 is similar to operation of the device described in document WO 2013/079685 A1. Therefore, unlike the first configuration, the spectrum of the periodic signal applied to the input of the first multiplier circuit 108 in this second configuration only comprises a single line (considering that the adjacent lines present, if any, have a negligible amplitude relative to the amplitude of the principal line), which prevents spectrum spreading of the transmitted RF.sub.TX (signal.

(58) Therefore in this second embodiment, the user can choose between the first configuration in which the consumption of the device 100 is reduced because the ILO 136 is not used, and the second configuration which, at the price of a higher consumption, transmits an RF signal for which the spectrum occupies a narrower width, which may be useful for example when the transmission channel reserved for transmission of the RF.sub.TX signal is narrow or to prevent pollution of adjacent channels.

(59) As in the first embodiment, the reception part 114 of the device 100 comprises the reception antenna 116, the low noise amplifier 118, the second multiplier circuit 120 and the second baseband processing circuit 122. As for the first multiplier circuit 108 in the transmission part 104, the second multiplier circuit 120 receives either the TORP signal directly as input when the switches 130 and 132 are in the first configuration, or the signal outputted by the ILO 136. In this configuration, only one spectral band of the RF.sub.RX signal can be folded rather than all bands.

(60) The variants of the first embodiment previously described (use of the TORP signal only in transmission or reception, the device 100 corresponding only to a transmission or reception device, one or two circuits 106 generating coherent or non-coherent TORP signals) may also be applied for this second embodiment.

(61) According to another variant of this second embodiment, it is possible that the output of the second switch 132 is only connected to the input of one of the two multiplier circuits 108, 120, and that the input of the other multiplier circuit 108, 120 is directly connected to the output of the circuit 106 or the output of the ILO 136. Thus, the choice between the first and second configurations of switches 130 and 132 only concerns the transmission part 102 or the reception part 114, the other part not being affected by this configuration change.

(62) In another variant, the device 100 may comprise two other switches connected to the circuit 106, to the electrical connection 134 and to the ILO 136 in a similar manner to the switches 130 and 132, but that are controlled to be in the first or the second configuration independently of the configuration in which the switches 130 and 132 are. In this case, the output of the second switch 132 may be connected only to the input of the first multiplier circuit 108 (and not to the input of the second multiplier circuit 120), and the output of the second of the other two switches is only connected to the input of the second multiplier circuit 120 (and not to the input of the first multiplier circuit 108). With this variant, the emission part 102 and the reception part 114 can each operate in the first or second configuration independently of each other.

(63) FIG. 10 shows a third embodiment of a signal transmission and reception device 100.

(64) As in the first embodiment, the transmission part 102 of the device 100 comprises the first baseband processing circuit 104, the circuit 106 generating the TORP signal (formed by the PLL or frequency synthesis 124, the oscillator 126 and the controlled electrical power supply means 128 as in FIG. 9), the first multiplier circuit 108, the power amplifier 110 and the transmission antenna 112.

(65) The transmission part 102 of the device 100 also comprises a first switch 138 comprising a first input A connected to the output of a circuit 140 outputting a signal with a constant amplitude on this output corresponding to the amplitude of a bit with value 1 and a second input B connected to the output of the circuit 104 on which the BB.sub.TX signal is outputted, and an output connected to an input of the first multiplier circuit 108. The transmission part 102 also comprises a second switch 142 comprising a first input A connected to the output of the circuit 104, a second input B connected to the output of the PLL 124 and an output connected to the control input of the controlled electrical power supply means 128.

(66) In a first configuration (that corresponds to the case shown in FIG. 10), each switch 138, 142 outputs the signal applied onto its input B. In this case, the electrical power supply means 128 are controlled by the signal outputted by the PLL 124 and the first multiplier 108 receives the TORP signal and the BB.sub.TX signal as input. In this first configuration, operation of the transmission part 102 of the device 100 according to the third embodiment is similar to that described previously for the device 100 according to the first embodiment.

(67) In a second configuration, each switch 138, 142 outputs the signal applied on its input A. In this case, the electrical power supply means 128 are controlled by the BB.sub.TX signal, and the first multiplier 108 receives the signal outputted by the oscillator 126 (which in this case is not a TORP type signal considering that the means 128 are controlled by the BB.sub.TX signal) and the signal with value 1 outputted by the circuit 140, on its input. Therefore in this second configuration, the transmission part 102 makes an OOK (On Off Keying) modulation of the BB.sub.TX signal directly, and then a transmission of this modulated signal.

(68) Therefore in this third embodiment, the user can choose between two transmission modes of the BB.sub.TX signal: either in OOK modulation, or transposed into RF frequency. In OOK modulation, data to be transmitted directly control the TORP signal generator and the signal is generated directly in the RF band.

(69) As in the first embodiment, the reception part 114 of the device 100 comprises the reception antenna 116, the low noise amplifier 118, the second multiplier circuit 120 and the second baseband processing circuit 122. In this case, the reception part 114 is used when the switches are in the first configuration, in other words when the oscillator 126 outputs the TORP signal.

(70) The variants of the first and the second embodiments described above may also be applied for the third embodiment.

(71) According to another variant of this third embodiment, the reception part 114 may comprise another circuit generating a TORP signal different from that used for the transmission, so that when the transmission part 102 makes an OOK modulation and therefore the oscillator 126 does not output a TORP signal, the reception part 114 can still make a signal reception using a TORP signal.

(72) According to another variant embodiment of the transmission part 102 of the device 100 according to this second embodiment, the circuit 140 may be replaced by a symbol generator capable of transmitting bits of information to be transmitted in a synchronised manner with the signal outputted by the PLL 124. The output of this symbol generator is connected to the first input A to the first switch 138 through a delay line or DLL, that synchronises the TORP signal outputted by the oscillator 126 and the signal outputted by the symbol generator, at the first multiplier circuit 108. Furthermore in this variant, the device 100 does not comprise the second switch 142 because the signal outputted by the PLL 124 is still applied on the control input of the power supply means 128. This other variant may be used when the TORP signal has to be synchronised with the signal containing information to be sent, in the second configuration making an OOK modulation of the signal to be transmitted.

(73) FIG. 11 shows a fourth embodiment of a signal transmission and reception device 100.

(74) The device 100 according to the fourth embodiment comprises elements previously described with reference to the second embodiment, and those previously described with reference to the third embodiment. Thus, in a first configuration in which each of the switches 130, 132, 138 and 142 are switched in a state in which their input or output referenced A in FIG. 11 is connected to other elements of the device 100, operation of the device 100 according to the fourth embodiment is similar to that previously described for the device 100 according to the second embodiment in the first configuration (TORP signal applied directly to the input of the multiplier circuits 108 and 120 for the transmission and reception of signals). In a second configuration in which each of the switches 130, 132, 138 and 142 are switched in a state in which their input or output referenced B in FIG. 11 is connected to the other elements of the device 100, operation of the device 100 in the fourth embodiment is similar to that previously described for the device 100 according to the second embodiment in the second configuration (TORP signal applied to the input of the ILO 136, the signal outputted by the ILO 136 being applied to the input of the multiplier circuits 108 and 120 for the transmission and reception of signals). In a third configuration in which each of the switches 130, 132, 138 and 142 are switched in a state in which their input or output referenced C in FIG. 11 is connected to the other elements of the device 100, operation of the device 100 according to the fourth embodiment is similar to that described above for the device 100 according to the third embodiment in the second configuration (OOK modulation of the signal to be transmitted).

(75) The different variants described above for the previous embodiments are applicable in a similar manner to the fourth embodiment of the device 100.

(76) The device 100 according to the different embodiments described above may be made using the 65 nm CMOS technology to make transmissions at frequency ranges between about 57 GHz and 66 GHz.