ES2374936B2 - PULSED WAVE SHAPE OSCILLATOR. - Google Patents

Abstract

A non-linear electric oscillator for generating pulses comprising: at least one active device (101, 151, Q {sub, 1}); a polarization network (120, 170, 470) to polarize and feed said active device (101, 151, Q {sub, 1}); a feedback network (110, 160, 460) connected to at least one port (451b, 451e) of said active device (101, 151, Q {sub, 1}); a non-linear transmission line (102, 152, 452). The non-linear transmission line (102, 152, 452) has a first end connected to a port (451c) of said active device (101, 151, Q {sub, 1}) different from the at least one port (451b, 451e ) to which the feedback network (110, 160, 460) is connected, the opposite end of said nonlinear transmission line (102, 152, 452) being the oscillator output, the oscillator being configured to propagate along said nonlinear transmission line (102, 152, 452) a pulsed waveform.

Description

Pulsed waveform oscillator.

Field of the Invention

The present invention belongs to the field of oscillators and, more specifically, to the electric oscillators that generate a periodic train of short duration pulses.

Background of the invention

In many electronics applications oscillators are needed that provide a high-speed pulse train (usually several gigahertz, GHz). To achieve this, sometimes linear systems are used that use a linear transmission line on which periodic waves propagate at the frequency of interest. In these systems, linear amplifiers are used to compensate for losses in the linear transmission line, so that the intensity of the sinusoidal signal is maintained at the output of the system and the desired oscillation is achieved. These linear oscillators are applied in the area of high speed electronics.

More recent research in the field of non-linear systems has shown that these are a real alternative to linear systems and have opened the door to possible applications that use non-sinusoidal waveforms in non-linear media. Thus, nonlinear transmission lines (NLTL) can be used to generate a short-duration pulse train and be applied to various fields, such as time domain reflectivity, High-speed sampling or ultra-wideband radar applications.

A nonlinear transmission line (NLTL) is made up of a certain number of varactor-coil cells (in English, inductance-varactor cell). The generation of the pulsed waveform is due to the combined effects of the nonlinear capacitance C (v) and the dispersion of the periodic line LC. This would result in one or more robust localized waves with permanent profile, also called solitons. An input pulse with pulse width measured at an amplitude value equal to half of the maximum amplitude (in English, full width at half maximum) TFWHM decomposes into N = 2fBTFWHM individual pulses or solitons, where fB is the frequency of Bragg of the NLTL and fB = 1 / (π \ √ (LCe ff)), where Ce ff is the capacitance of the effective varactor and L is the inductance of the cell. Each of the N pulses or solitons travels at their own speed and their propagation in this medium complies with some general rules. For high pulse amplitudes, the propagation speed increases, while TFWHM decreases. The solitons pass through each other without losing their characteristics, although during the time of overlap their joint amplitudes decrease (grow) when they travel in the same (opposite) direction. For the generation of a pulsed waveform of short or small duty cycle (in English, short-duty cycle), the objective is to obtain a single narrow pulse, which requires careful selection of the number of cells. Disregarding dissipation, the original input waveform is recomposed after a certain number of cells, in what is known as a recurrence phenomenon. The recurrence period is shorter for a higher input frequency and higher amplitude. To avoid the need for a periodic input signal, some design techniques for soliton oscillators have been proposed.

In this line, David S. Ricketts et al. described in On the Self-Generation of Electrical Soliton Pulses, IEEE Journal of Solid-State Circuits, Vol. 42, No. 8, August 2007, an electric soliton oscillator (or soliton generator) that generates a periodic and stable pulse train of electric solitons. Specifically, in this publication a 30-cell nonlinear transmission line (NLTL) is used as a parallel feedback network of an amplifier that incorporates a threshold-dependent gain attenuation mechanism. The objective is to attenuate the solitons of smaller amplitude, while amplifying those with amplitude greater than a certain threshold, and thus eliminate the risk of instabilities caused by the coexistence of multiple oscillation modes.

However, this oscillator has a series of limitations: On the one hand, for its operation, it needs a very specific amplifier, which is also dependent on polarization. On the other hand, it is essential to feedback the ampli fi er using the non-linear transmission line. All this makes the actual implementation of the oscillator very complicated. Because at microwave frequencies or in millimeter bands, the most widespread design techniques are those of the frequency domain, the application of the amplifier proposed by Ricketts makes the work of design engineers difficult, since their description and operation must be verified in the domain of time. On the other hand, oscillators designed according to that method cannot be used directly. They require additional circuitry for the extraction of the signal and its subsequent use. Furthermore, when working with a feedback topology, in which pulses at other frequencies could also be generated, it cannot be guaranteed that the only possible solution is the one that has been proposed as a design objective. This implies that precise complementary analyzes are made on the stability and robustness of the design with respect to variations in the different parameters of the circuit.

The oscillator topology in reflection (from English, re fl ection oscillator topology) has been studied by O.O. Yildirim et al. In Re fl ection Soliton Oscillator, IEEE Transactions on Microwave Theory and Techniques, vol. 57, nº 10, pages 2344-2353, Oct 2009, where the non-linear transmission line constitutes the load of a reflection amplifier with an adaptive power scheme, similar to that of Ricketts et al. On On the Self-Generation of Electrical Soliton Pulses.

International patent application WO 2007/030485 A2, of which David S. Ricketts is an inventor, also refers to a non-linear pulsed oscillator implemented by a closed (feedback) circuit formed by a non-linear transmission line and a non-ampli fi er linear distributed. This oscillator has the same disadvantages as the previous one.

Summary of the Invention

The present invention seeks to solve the aforementioned drawbacks by means of a non-linear pulsed electric oscillator.

Specifically, in a first aspect of the present invention, a non-linear electric oscillator is provided to generate pulses comprising: at least one active device; a polarization network to polarize and feed said active device; a feedback network connected to at least one port of said active device; and a nonlinear transmission line. The non-linear transmission line has a first end connected to a port of said active device other than at least one port to which the feedback network is connected, the opposite end of said non-linear transmission line being the oscillator output, being the oscillator configured to propagate a pulsed waveform along said nonlinear transmission line.

Preferably, the at least one active device is implemented by one or more transistors.

The feedback network is configured to ensure that the oscillation starts in small signal conditions and the stable oscillation in permanent mode.

Preferably, the non-linear transmission line comprises a plurality of varactor-coil cells.

In the previous case, each output pulse has a minimum duration (TFWHM) given by TFWHM = 1 / (2fB), where fB is the Bragg frequency of the nonlinear transmission line and fB = 1 / (π √ (LCe ff )), where Ce ff is the effective capacitance of the varactor of each cell of the NLTL and the inductance of said cell.

The number of coil varactor cells of said non-linear transmission line is chosen taking into account the equivalent delay produced by each of them and the ratio of the total delay to the frequency at which it is desired that the oscillator generates the pulses.

Specifically, the number of coil varactor cells of said non-linear transmission line is the number of cells that produce a total delay approximate to the desired oscillation period T0, where T0 = 1 / f0, where f0 is the oscillation frequency.

Preferably, the characteristic impedance of the non-linear transmission line is set to have a sufficiently low value to be able to connect the end of said non-linear transmission line that coincides with the output of the oscillator on a load of substantially greater value than said characteristic impedance

Preferably, the value of the components that form the feedback network is chosen so that the real part of the admittance presented by the at least one active device connected to the non-linear transmission line is less than zero at the oscillation frequency.

Preferably, the oscillator is set to provide a pulsed signal at a microwave frequency.

The oscillator preferably provides a pulsed signal at a frequency that is in the band between 300 MHz and 30 GHz.

As can be seen, the oscillation start conditions are imposed on a port of the transistor different from the port to which the NLTL is connected, so that the flexibility in the design of the NLTL is increased. Preferably, a short NLTL section is used, with a small number of varactor-coil cells and the reactive termination is optimized to reduce the duty cycle. No adaptive control is necessary because the waveform seen by the transistor network does not exhibit low amplitude pulses. In addition, the pulsed oscillator signal can be used directly without the need for amplification stages or impedance matching. The problem of possible coexistence of other oscillation modes is minimized since since the first design stage it is imposed that the starting conditions be met only at the desired oscillation frequency.

The advantages of the invention will become apparent in the following description.

Brief description of the fi gures

In order to help a better understanding of the characteristics of the invention, in accordance with a preferred example of practical realization thereof, and to complement this description, a set of drawings is attached as an integral part thereof, whose character is Illustrative and not limiting. In these drawings:

Figures 1a and 1b show the basic scheme of two possible implementations of the oscillator of the invention.

Figure 2 shows a non-linear transmission line, implemented with discrete coils and varactors with non-linear capacity C (V).

Figure 3 shows an oscillator scheme according to an embodiment of the invention, separating the active subnet from the passive subnet, for the oscillator design.

Figure 4 shows an example of an oscillator implementation according to the invention. The oscillator in the example has been implemented with a BJT transistor and discrete elements in hybrid technology, on a glass fiber substrate.

Figure 5 shows the waveform at the output of the oscillator in Figure 4.

Detailed description of the invention

In this text, the term "comprises" and its derivatives (such as "comprising", etc.) should not be understood in an exclusive sense, that is, these terms should not be construed as excluding the possibility that what has been described and defined may include elements, stages, etc. additional.

In addition, the terms "approximately", "substantially", "around", "ones", etc. they should be understood as indicating values close to which these terms accompany.

The oscillator circuit is described below, whose output waveform corresponds to a short-lived pulse train and is repeated at intervals T0 = 1 / f0, where fo is the oscillation frequency. The range of oscillation frequencies that can be obtained with the circuit described herein may vary between the limits comprised in the band of 3 kHz -300 GHz (radiofrequency) Preferably, this range varies in the band comprised between 300 MHz and 30 GHz.

For a better description of the circuit, the oscillator is separated into two subnets, one active and one passive.

Figure 1A represents a possible implementation of the proposed oscillator, consisting of an active subnet 100, a passive subnet 110 and a polarization network 120. The active subnet 100 in turn comprises one or more active devices 101 and a non-linear transmission line NLTL 102. The design is based on a feedback topology, where passive subnet 110 is the feedback network. Note, in comparison with the circuit proposed by Ricketts et al and mentioned in the state of the art section, that the NLTL nonlinear transmission line of that circuit is an explicit and integral part of the oscillator feedback network, while in this case, the non-linear transmission line 102 is not part of the feedback network 110 (passive subnet). The end of the non-linear transmission line 102 that is not attached to the active element or elements 101 is connected to the output of the oscillator, as shown in Figure 1A.

Figure 1B represents a variant of the proposed oscillator, consisting of an active subnet 150, a passive subnet 160 and a polarization network 170. The active subnet 150 in turn comprises one or more active devices

151.

In a possible embodiment, the active subnet 150 also comprises a non-linear transmission line NLTL

152.

Alternatively, this NLTL 152 nonlinear transmission line is outside the active subnet 150. Figure 1B shows both possibilities expressed with dashed lines. Passive subnet 160 is the oscillator feedback network. As in the implementation of Figure 1A, the nonlinear transmission line 152 is not part of the feedback network 160 (passive subnet). The end of the non-linear transmission line 152 that is not attached to the active device or devices 151 is connected to the output of the oscillator, as shown in Figure 1B.

Figure 2 shows a possible implementation of the non-linear transmission line (NLTL) of the circuits of Figures 1A and 1B, implemented with discrete coils and varactors with non-linear capacity C (V). Each pair L-C

(V) is known as varactor-coil cell. This implementation of the NLTL should not be considered limiting, but merely illustrative. Alternatively, other forms of NLTL implementation can be used.

Figure 3 is similar to Figure 1B. Figure 3 also shows the impedance at the output of the passive subnet 360 Ypas and the impedance at the input of the active subnet 350 Yact. In addition, the scheme in Figure 3 corresponds to the particular case of Figure 1B in which the non-linear transmission line 352 is not part of the active subnet 350. Therefore, the active subnet 350 is also the active device or devices 351.

In any of the embodiments represented, the active device 101 151 351 is implemented by one or more transistors. In all possible implementations, the starting conditions of the oscillation are imposed on a port of the transistor different from the port to which the NLTL is connected, so that the flexibility in the design of the NLTL is increased. In addition, it is imposed that the starting conditions be met only at the desired oscillation frequency.

Preferably, a short NLTL section is used, with a small number of varactor-coil cells and the reactive termination is optimized to reduce the duty cycle. The number of cells is generally determined by the equivalent delay produced by each of them and the ratio of the total delay to the frequency at which it is desired that the circuit generates the pulses and depends on both the L value and the effective value of C In this case, the size of the NLTL is reduced to the number of cells that produce a total delay approximate to the desired oscillation period T0. Thus, the problem of possible coexistence of other oscillation modes is minimized. Other works, such as Ricketts, use NLTLs of lengths that often exceed the value of T0, which makes it possible for other modes of operation to appear at frequencies other than the design objective. For this reason, the Ricketts oscillator requires an adaptive amplifier to try to eliminate those other modes.

The active subnet 100 150 350 comprises a three-door device (transistor), properly polarized by means of the corresponding polarization network 120 170 370 to operate in the linear zone of its characteristic curves. Depending on the characteristics of the oscillator and the design specifications, it is possible to use two or more transistors in the active subnet (eg ring oscillators, differential oscillators, etc.). Since the three-door devices are manufactured in different technologies (SiGe, AsGa, CMOS, etc.) it is also possible to choose a different operating point than the linear zone (cut, saturation, pinch-off, etc.).

The passive subnet 110 160 360 of the oscillator consists of discrete components (resistors, coils, capacities, etc.) and distributed (transmission lines) that are not included in the active subnet. In this subnet 110 160 360, all the elements that constitute the oscillator feedback network and which are necessary to ensure the start of the oscillation in small signal conditions and the stable oscillation in permanent regime are included.

The oscillator feedback network can be considered in series or parallel. An example of a series feedback network is that shown in Figure 1A (110), while an example of a parallel feedback network is that shown in Figure 1B (160). In series feedback, there is no obvious connection between the three terminals of the transistor, while in parallel feedback, discrete or distributed elements of the passive subnet interconnect said terminals explicitly. These two configurations of the feedback network are described in the literature and the values of the components that comprise it must be chosen in such a way that the oscillation at the desired frequency is ensured, the use of different types of resonant circuits being very common in around that frequency. The specific configuration of the feedback network 110 160 360 that is chosen is outside the scope of the invention.

The polarization network 120 170 370 of the active device or active subnet was mentioned previously. This network is designed to provide the active subnet 100 150 350 with adequate power supply (voltage and current) so that the operating point of the transistor or transistors is adequate. Unless some differential topology is used (common rejection mode), the polarization network must be properly designed to present the maximum isolation between the periodic oscillation, and their respective harmonics, and the direct current. In the case of using discrete elements, it is common to use inductive elements that have a very high impedance at the frequency of the periodic signal (DC feeds) in combination with capacitors that have a low impedance at the same frequency. If the polarization network is designed with microstrip transmission lines, quarter wave lines can be used in combination with radial or rectangular sections that resonate with the oscillation frequency. The specific configuration of polarization network 100 150350 that is chosen is outside the scope of the invention.

To obtain the pulsed waveform at the oscillator output, a non-linear NLTL transmission line is used. Unlike the oscillator described by Ricketts et al., The nonlinear transmission line 102 152 352 of the present oscillator is not part of the feedback network or passive subnet. On the contrary, the end of the nonlinear transmission line in the oscillator described herein that is not attached to the transistor forms the output of the oscillator, as shown in Figures 1A, 1B and 3.

As indicated in the section related to the state of the art, in the case of electrical circuits, such as this oscillator, the non-linear transmission line is generally formed by a series connection of inductive elements (coils, lines of transmission, etc.) with an equivalent inductance L, periodically charged with non-linear capacities (eg varactors) with voltage-dependent capacity between their terminals C (V). In a lossless line, if the values of the LC (V) elements of the NLTL are properly chosen, so that nonlinearity is compensated with the dispersion of the transmission line, a family of pulses with similar characteristics, called solitons , can travel along the transmission line without altering its shape or amplitude. This family of pulses corresponds to the solutions of the Korteweg-de Vries equation (KdV). In practice, the inductive and capacitive components of the NLTL have some type of resistive element associated, which translates into the gradual attenuation of the pulse as it travels through the NLTL. As it has already been said, the number of cells is generally determined by the equivalent delay produced by each of them and the ratio of the total delay to the frequency at which it is desired that the circuit generates the pulses and depends so much on the value L as of the effective value of C.

To facilitate the extraction and direct use of the oscillator pulsed signal, the characteristic impedance of the

√

NLTLZc = L / Co, where Co = C (0), is set at a sufficiently low value to be able to connect the end end of the NLTL (oscillator output) on a load of value Zc << ZL. The chosen values of L and C are also chosen taking into account that for very high Bragg fB frequency values, a larger number of L-C cells is needed to form the pulse.

Once the values of the NLTL 102 152 352 are defined, the values of the feedback network components 110 160 360 are calculated, so that the real part of the admittance presented by the active subnet 101 151 351, connected to the NLTL 102 152 352, be less than zero at the oscillation frequency f0. That is to say:

For this, a process of adjusting the values of the feedback network 110 160 360 of the transistor (active device 101 151 351) is performed, while the NLTL 102 152 352 is connected to the port from which it is to be extracted the signal pulsed and charged at the other end by an ideal reactive load. During this value adjustment process, it must be ensured that for all possible reactive terminations, the impedance of the active subnet is negative at the oscillation frequency f0. Once the condition Re (Yact) <0 is fulfilled, the remaining components of the passive subnet are calculated so that the starting conditions of the oscillation at f0 are met in a small signal mode. That is to say:

To obtain the desired waveform, the amplitude at the input of the NLTL 102 152 352 needs to be large enough. This requirement is met by the circuit's own oscillation, which instead depends on the parameters of the NLTL. Calculated the oscillation stationary waveform, the value of the reactive load of the NLTL is recalculated to reduce the duration of the pulses, maintaining the oscillation frequency at the value f0. This process is carried out using an auxiliary generator until the desired pulse duration value is obtained. The minimum pulse duration that can be obtained is determined by the TFWHM parameter, which is calculated as TFWHM = 1 / (2fB). Having designed the NLTL taking into account that Zc is significantly less than ZL, the connection of the terminal load does not affect the oscillation or the duration of the pulse. If necessary, it is possible to use an impedance transformer to connect loads of a particular ZL value.

Figure 4 shows an example of a 1.2 GHz oscillator circuit (f0) according to the previous description. In this case, the active device is a bipolar transistor Q1 polarized in the linear zone of its characteristic curves. The polarization voltages Vcc and Vbb are applied to the collector and base by means of the resistors Ra and Rb, respectively. The polarization can also be carried out with a single direct current voltage if the Ra and Rb resistors are replaced by an equivalent resistive divider. The coils Lb are calculated to offer sufficient insulation between polarization and oscillation.

In this case, the non-linear transmission line NLTL 452 has been connected to the collector terminal 451c and is isolated from the polarization network 470 by means of the capacities Cb. Despite not being represented, the NLTL 452 also includes a polarization network to adjust the capacity value of the varactors that comprise it. The values of the coils L and the capacity Cj0 of the varactors have been calculated so that the Bragg frequency is around 11 GHz and the characteristic impedance of the NLTL 452 is approximately 10 Ohm. The active subnet, formed by the transistor, the Ze load, the L2 coil and the NLTL 452, (note that in this example the NLTL nonlinear transmission line does form part of the active subnet) has a negative real part of the admittance of input to the oscillation frequency, as described above. The parallel LC circuit (Cp and Lp) connected to the base terminal 451b of the transistor has been calculated so that the oscillation start conditions are met.

Once the steady state oscillation is obtained, the value of the reactive load connected at the other end of the NLTL 452 has been optimized, determining that the optimum value in this case is 2 L. After this optimization process, it is obtained a reduction in pulse duration, resulting in a duty cycle of about 5%. Finally, the design is completed by connecting a 50 Ohm load to the end of the NLTL. Since this value is higher than the characteristic impedance of the line, it does not affect the duty cycle or the amplitude of the oscillation.

The waveform at the output of the oscillator is presented in Figure 5. The pulse duration, defined according to the TFWHM, is 43.85 ps, resulting in a duty cycle of around 5%. This value approximates the minimum pulse duration previously defined TFWHM = 1 / (2fB).

As can be seen, the oscillation start conditions are imposed on a port of the transistor different from the port to which the NLTL is connected, so that the flexibility in the design of the NLTL is increased. As a short NLTL section is used, with a small number of varactor-coil cells, reactive termination is optimized to reduce the duty cycle. By using a number of total delay cells approximately equal to the period of the oscillation, the propagation of other oscillation modes is avoided. Therefore, a polarization dependent gain amplifier is not needed, as in Ricketts' work, because there are no other modes of operation at a frequency other than fo. In addition, the pulsed signal offered by the oscillator can be used directly without the need for amplification stages or impedance matching. The problem of possible coexistence of other oscillation modes is minimized since since the first design stage it is imposed that the starting conditions be met only at the desired oscillation frequency. In addition, the proposed oscillator allows obtaining a pulsed waveform with a duty cycle of 5% at 1.2 GHz.

The proposed oscillator can be implemented in hybrid or monolithic technology. The oscillator in the example has been constructed using hybrid technology, using a silicon NPN transistor (BFP405-In fi neon), mounted on a CuCladTM glass fiber substrate (εr = 2.17, h = 0.8 mm), using mechanical techniques, instead of chemical process, to increase the accuracy of the physical dimensions of the transmission lines. Schottky varactors and discrete inductors have been used for the implementation of the NLTL.

The invention can be applied, for example, to re fl ectometry in the temporal domain, high-speed sampling or in ultra-wideband radar applications.

Claims (10)

1. A nonlinear electric oscillator for generating pulses comprising:

-

at least one active device (101, 151, Q1);

-

a polarization network (120, 170, 470) to polarize and feed said active device (101, 151, Q1);

-

a feedback network (110, 160, 460) connected to at least one port (451b, 45le) of said active device (101, 151, Q1);

-

a non-linear transmission line (102, 152, 452);

characterized in that said non-linear transmission line (102, 152, 452) has a first end connected to a port (451c) of said active device (101, 151, Q1) different from at least one port (451b, 45le) to the that the feedback network (110, 160, 460) is connected, the opposite end of said non-linear transmission line (102, 152, 452) being the oscillator output, the oscillator being configured to propagate along said line Nonlinear transmission (102, 152, 452) a pulsed waveform.

2.

The oscillator of claim 1, wherein said at least one active device (101, 151, Q1) is implemented by one or more transistors.

3.

The oscillator of any of the preceding claims, wherein said non-linear transmission line (102, 152, 452) comprises a plurality of varactor-coil cells.

Four.

The oscillator of claim 3, wherein each output pulse has a minimum duration (TFWHM) given by TFWHM = 1 / (2fB), wherein fB is the Bragg frequency of the nonlinear transmission line (102, 152, 452) and fB = 1 / (π √ (LCe ff)), where Ce ff is the capacitance of the effective varactor of each varactor-coil cell and L is the in

ductance of said cell.

5.

The oscillator of claims 3 or 4, wherein the number of coil varactor cells of said non-linear transmission line (102, 152, 452) is chosen taking into account the equivalent delay produced by each of them and the ratio of the delay total with the frequency at which you want the oscillator to generate the pulses.

6.

The oscillator of any one of claims 3 to 5, wherein the number of coil varactor cells of said non-linear transmission line (102, 152, 452) is the number of cells that produce a total delay approximate to the desired oscillation period T0, where T0 = 1 / f0, where f0 is the oscillation frequency.

7.

The oscillator of any of the preceding claims, wherein the value of the components that form the feedback network (110, 160, 460) are chosen so that the real part of the admittance presented by the at least one active device (101, 151, Q1) connected to the non-linear transmission line (102, 152, 452) is less than zero.

8.

The oscillator of any of the preceding claims, configured to provide a pulsed signal at a microwave frequency.

9.

The oscillator of any of the preceding claims, configured to provide a pulsed signal at a frequency in the band between 300 MHz and 30 GHz.

SPANISH OFFICE OF THE PATENTS AND BRAND Application no .: 201000636 SPAIN Date of submission of the application: 14.05.2010 Priority Date: REPORT ON THE STATE OF THE TECHNIQUE 51 Int. Cl.: H03B5 / 08 (2006.01) RELEVANT DOCUMENTS

Category

56 Documents cited Claims Affected

TO

WO 2007030485 A2 (HARVARD COLLEGE et al.) 15.03.2007, paragraphs [0040-0052]; figures. 1-9

TO

"Reflection Soliton Oscillator" (YILDIRIM O O; RICKETTS D S; HAM D). 01.10.2009. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, Vol 57, Nr 10, Page 2344-2353. ISSN 0018-9480. 1-9

TO

"On the Self-Generation of Electrical Soliton Pulses" (RICKETTS D S; XIAOFENG LI; NAN SUN; KYOUNGHO WOO; HAM D). 01.08.2007. IEEE JOURNAL OF SOLID-STATE CIRCUITS, Vol 42, Nr 8, p 1657-1668. ISSN 0018-9200. 1-9

TO

"Applications of Pulsed-Waveform Oscillators in Different Operation Regimes" (PONTON M; RAMIREZ F; SUAREZ A; PASCUAL J P). 01.12.2009. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, Vol 57, Nr 12, Page 3362-3372. ISSN 0018-9480. 1-9

TO

"Analysis and design of soliton oscillators using harmonic balance" (PONTON M; RAMIREZ F; SUAREZ A; PASCUAL J P). 07.06.2009. Microwave Symposium Digest, 2009. MTT '09. IEEE MTT-S International, p. 1485-1488. ISBN 978-1-4244-2803-8; ISBN 1-4244-2803-3. 1-9

TO

"Modeling Soliton Pulses in Nonlinear Transmission Lines for Millimeter Wave Generation" (FERRAN MARTIN). 01.10.2000. European Microwave Conference, 2000. 30th, p. 1-4. 1-9

Category of the documents cited X: of particular relevance Y: of particular relevance combined with other / s of the same category A: reflects the state of the art O: refers to unwritten disclosure P: published between the priority date and the date of priority submission of the application E: previous document, but published after the date of submission of the application

This report has been prepared • for all claims • for claims no:

Date of realization of the report 01.02.2012

Examiner J. Calvo Herrando Page 1/4

REPORT OF THE STATE OF THE TECHNIQUE Application number: 201000636 Minimum documentation searched (classification system followed by classification symbols) H03B Electronic databases consulted during the search (name of the database and, if possible, terms of search used) INVENES, EPODOC, WPI State of the Art Report Page 2/4  WRITTEN OPINION Application number: 201000636 Date of Written Opinion: 01.02.2012 Statement

Novelty (Art. 6.1 LP 11/1986)

Claims Claims 1-9 IF NOT

Inventive activity (Art. 8.1 LP11 / 1986)

Claims Claims 1-9 IF NOT

The application is considered to comply with the industrial application requirement. This requirement was evaluated during the formal and technical examination phase of the application (Article 31.2 Law 11/1986).  Opinion Base.- This opinion has been made on the basis of the patent application as published. State of the Art Report Page 3/4  WRITTEN OPINION Application number: 201000636 1. Documents considered.- The documents belonging to the state of the art taken into consideration for the realization of this opinion are listed below.

Document

Publication or Identification Number publication date

D01

WO 2007030485 A2 (HARVARD COLLEGE et al.) 03.15.2007

D02

"Reflection Soliton Oscillator" (YILDIRIM O O; RICKETTS D S; HAM D). 01.10.2009

D03

"On the Self-Generation of Electrical Soliton Pulses" (RICKETTS D S; XIAOFENG LI; NAN SUN; KYOUNGHO WOO; HAM D) 01.08.2007

D04

"Applications of Pulsed-Waveform Oscillators in Different Operation Regimes" (PONTON M; RAMIREZ F; SUAREZ A; PASCUAL J P) 01.12.2009

D05

"Analysis and design of soliton oscillators using harmonic balance" (PONTON M; RAMIREZ F; SUAREZ A; PASCUAL J P). 07.06.2009

D06

"Modeling Soliton Pulses in Nonlinear Transmission Lines for Millimeter Wave Generation" (FERRAN MARTIN). 01.10.2000

2. Statement motivated according to articles 29.6 and 29.7 of the Regulations for the execution of Law 11/1986, of March 20, on Patents on novelty and inventive activity; quotes and explanations in support of this statement The claimed invention is about a non-linear pulsed wave oscillator. Document D01 is considered to be the closest prior art document to the object claimed.  R1 independent claim The claimed invention differs mainly from the cited documents in that the nonlinear pulsed wave oscillators described by said documents need feedback and depend on polarization. However, the claimed invention implies an improved effect compared to the state of the art since it does not need to feedback the amplifier using the nonlinear transmission line (NLTL), which facilitates the actual implementation of the oscillator. Furthermore, it is not considered obvious that a person skilled in the art obtains the invention from the aforementioned documents. Therefore, the object of claim R1 meets the requirements of novelty and inventive activity (Art. 6.1 and Art. 8.1 LP).  Claims R2-R9 Claims R2-R9 are dependent on claim R1 which add features of more limited scope and as they also meet the requirements of novelty and inventive activity set forth in Art. 6.1 and Art. 8.1 LP State of the Art Report Page 4/4