MXPA00003577A

MXPA00003577A - Methods and apparatus for measuring nonlinear effects in a communication system and for selecting channels on the basis of the results

Info

Publication number: MXPA00003577A
Application number: MXPA/A/2000/003577A
Authority: MX
Inventors: Amnon Silberger; Brian Butler; Leonard Schiff
Original assignee: Qualcomm Incorporated
Priority date: 1997-10-14
Filing date: 2000-04-12
Publication date: 2001-03-05

Abstract

A method and appararatus for accurately determining the operating characteristics or impact of nonlinear effects on devices or communication systems transferring orthogonally coded spread-spectrum communication signals. A Walsh Power Ratio, is used to more accurately determine system response. This information can be used by power control loops in controlling or adjusting the operation of nonlinear elements or stages such as high power amplifiers in orthogonal CDMA communication systems to provide improved system response. The information can also be employed in assigning channels to systems users, and to proceed with physical changes to system hardware. The measurements used to formulate the WPR can be made to individual components or to entire systems by injecting communication signals in multiple channels containing data, and leaving at least one empty channel. The received power per channel on the output side of the system or device is then measured. A ratio of power density for the empty to the active channels is then formed. The determination of WPR for a system or components can be realized during periods of operation through periodic transfer of test signals either at allocated times or by interleaving among existing traffic signals in the system.

Description

METHOD AND APPARATUS FOR MEASURING NONLINEAR EFFECTS IN A COMMUNICATION SYSTEM AND TO SELECT BASE CHANNELS TO THE RESULTS Field of the Invention The present invention relates to non-linear apparatus and more particularly to a method for determining the effects of the characteristics of the non-linear apparatus on the transfer of signals within a communication system. The present invention further relates to a method for using the energy ratio in channels of the active system, against inactive, in an orthogonal CDMA communication system and, more specifically, using a Walsh Energy Ratio to control the operation of non-linear stages. such as power amplifiers.

Background of the invention A type of multiple access communication system used to transfer information among a large number of users of the system is based on the techniques of diffusion of the spectrum of multiple access of the division code (CDMA). Said communication systems are described in the teachings of the North American Patent No. 4,901, 307, which was issued on February 13, 1990 under the title of "Multiple Access Spectrum Broadcast Communication System, Using Satellite Repeater Repeaters". or Terrestrial ", and US Patent No. 5,691, 974, issued on November 25, 1997, under the title" Method and Apparatus for Using Transmitted Energy of the Whole Spectrum in a Spectrum Diffusion Communication System for the Time and Energy Tracking of the Individual Receptor Phase, both assigned to the power of the present invention and incorporated as a reference, These patents describe communication systems in which users or subscribers of the mobile or remote system, generally use transmitters to communicate with other users of the system or with desired signal receivers, such as a change network connected to the public telephone. res communicate signals through input and output circuits and satellite or, from land based stations (also referred to as field sites or fields), using the CDMA spectrum broadcast communication signals. In a typical spectrum broadcast communication system, one or more groups or pairs of preselected pseudo-random noise code sequences are used to modulate or 'disperse' the user's information signals over a predetermined spectral band, before modulating upon a conveyor to transmit in the form of communication signals. PN dispersion is a method of transmitting spectrum diffusion that is well known in the art and produces a communication signal with a bandwidth much greater than that of the underlying data signal. In the communication link of the base station or input and output circuit for the user, also referred to as a forward link, the PN broadcast codes or binary sequences are used to distinguish between the signals transmitted by different base stations or between different beam signals, satellites or input and output circuits, as well as between multiple path signals. In the communication link of the terminal for the base station or for the input and output circuit, also referred to as a reverse link, the PN diffusion codes or binary sequences are used to distinguish between intentional signals for lightning, satellites or circuits. different entry and exit, as well as multiple path signs. These codes are normally shared by all the communication signals within a given field or ray and, the time offset or shifted between the rays or adjacent elements to create different diffusion codes. The time shifts provide single beam detectors that are useful for transmitting from beam to beam and for determining the synchronization of the signal to the basic synchronization of the communication system. In a typical CDMA spectrum broadcast communication system, channelization codes are used to distinguish between intentional signals for different users within a field, or between user signals transmitted within a satellite ray or sub-beam, in a forward link. That is, each user's transmitter has its own orthogonal channel provided in the forward link, using a single 'coverage' or 'channel' orthogonal code. The Walsh functions are generally used to implement the channeling codes, with a typical length being of the order of 64 code chips for terrestrial systems and 128 code chips for satellite systems. In this distribution, each Walsh function of the 64 or 128 chips is usually referred to as a Walsh symbol. The derivation of Walsh codes is fully described in US Patent No. 5,103,459, entitled "System and Method for Generating Signal Wave Forms in a CDMA Cellular Telephone System", which was granted to the successor in title of this present invention. incorporated to it as reference.

The input and output circuits and the base stations and satellites, used in the systems described above, use high power amplifiers (AAPs), to increase the energy of the signals being transferred to, and from the satellites, input circuits and the user's output and terminals in, or served by, the communication system. It is desirable to achieve a significant amount of energy increase in the signals, but at the same time it is desirable to spend as little energy as possible in doing so. That is, to expend energy to amplify a signal, but no more than necessary to achieve a desirable communication link. This refers to the desire to conserve energy and, consequently, the energy sources needed to power the amplifiers; and to minimize the energy of the signal, to diminish the mutual signal interference and increase the capacity of the system. It is also important to recognize that in a satellite communication system, the amount of energy available to transmit the signal is limited by the power generation capacity of the satellite. To optimize the use of this energy, it must be distributed among traffic signals, those intended to transfer information to, and from users and pilot signals, those carefully intended to act as phase and time references. In case that very little energy is distributed to the pilot signal, the user's terminals can not accumulate enough energy to synchronize their receivers with an input and output circuit or base station. Conversely, in the event that too much energy is transmitted from the pilot signal, the amount of energy available for the traffic signals is reduced, and therefore, for the number of users that can be supported.

Therefore, to maximize the user's capacity that can be handled by a satellite, the amount of the pilot signal energy transmitted must be precisely controlled. In addition, there are other shared sources, such as location and synchronization signals used to transfer information to the system, which act as shared sources similar to pilot signals. These signals also affect energy consumption in the satellite or other communication systems limited by energy or controlled by energy. In order to increase the capacity of the system, it is also desirable to minimize the amount of energy present in these signals, to decrease mutual interference. Power amplifiers in communication systems that operate at high levels of intermodulation, such as those described above, generally operate near their saturation point. The saturation point is the point at which the output power of the amplifier no longer increases with the increase of the input energy. That is, after the saturation point has been reached, the energy output of the power amplifier is substantially constant without considering the input power. Therefore, the power amplifier exhibits a lack of linearity in its operation near the saturation point. The saturation region is also referred to as the compression gain region. Intermodulation is a term used to describe the lack of linearity. For example, when a non-linear apparatus operates on a signal having multiple-spectrum components to produce an output signal, the output signal is comprised of spectrum components that were not present in the original input signal. Some of the components can be removed by filtration. Components that can not be removed by filtration provide an elevation for nonlinear distortion. These components are commonly referred to as intermodulation products. This intermodulation causes undesirable distortion in most communication systems. For example, in a CMDA communication system, a CDMA signal is amplified before transmitting in a communication channel. A non-linear power amplifier is commonly used to provide this amplification. The CDMA signals transmitted in real communication systems often exhibit a non-constant envelope which may result from a plurality of CDMA signals being multidirected together to form a single multidirectional CDM signal. Said signal may result from several CDMA signals being combined in a single carrier to form a CDMA channel, or several CDMA channels in different frequencies that are being combined within a signal for transmission. In any case, the multidirected CDMA signal exhibits a non-constant envelope. Other well-known causes can also provide an elevation for the non-constant envelope phenomenon. As a result, the input energy to the non-linear amplifier goes through the input power range of the amplifier. Because the non-linear amplifier is non-linear across its input range, the output signal exhibits undesirable non-linear effects such as intermodulation products. Non-linear distortion, such as that caused by intermodulation, is an undesirable effect, which can destroy the information content of a signal in a communication system. Unfortunately, non-linear distortion can also affect CDMA communication signal waveforms, such as those following the IS-95 standard, such that channels no longer remain orthogonal. In essence, the non-linear response causes the coded channels to "filter" or "bleed" into the other Traditionally, the operation of the power amplifiers and other non-linear elements used to generate and amplify the communication signals are quantified with charged tests of two tones, multiple tones and noise, in particular, the noise-charged tests are referred to as a Noise Energy Ratio, also called PER tests, and measure how much energy density is filtered within a narrow point or, They measure the noise injected into the non-linear apparatus under test, however, there are some key differences between the noise intermodulation performance and the direct sequence spectrum broadcast signals (SDS-SD). of the spectrum diffusion data is, what is referred to as a dimension, for example of the BPSK type, the envelope statistics of the form of SDS-SD wave, are different from the noise. Even where many Information signals are multidirected together, such as those discovered in CDMA communication systems (for CDM or CDMA), the SDS-SD waveform has significantly different envelope statistics than bandpass noise. , if these signals share the same conveyor frequency and conveyor phase. Bandpass noise has a probability density function (FDP) that is a chi-box with two different degrees of freedom of movement. The forward link CDMA channels or signals, which have many user or user signals (traffic channels), have an approximate FDP energy of chi-box with a degree of freedom of movement. The forward link CDMA type signals that make up the IS-95 standard are a special case of this, where the CDM or CDMA signals are maintained orthogonally with the Walsh codes. This form of coding can be referred to as an orthogonal CDMA or O-CDMA for a short modulation, but, it is still a BPSK modulation. The significant amounts of intermodulations in an IS-95 waveform mean that the channels are no longer orthogonal, "filter" or "bleed" into the other. The result of this filtering is that simple noise measurements in a channel, do not reflect an actual response or measure of the functioning of the communication system in a CDMA environment. This means that a Noise Energy Ratio (NPR) test can not be used simply to measure or determine the effects of power adjustments or the appropriate level of energy to be used with a particular amplification stage in a broadcast system. spectrum. This is real, because the noise in the system tends to change the energy in other ways within the orthogonal channels. Another point where noise performance is not necessarily a reflection of CDMA operation, is in the separation in which the AM / AM and AM / PM effects are referenced. Both of these are well known to affect traditional noise measurement techniques, such as NPR. However, the coherent BPSK demodulation is much more sensitive to AM / AM than to AM / PM. To illustrate this point, the output power and phase characteristics of a conventional non-linear power amplifier are illustrated in Figure 1. In Figure 1, a curve 102 illustrates the phase of the output against the phase of a sinusoidal input wave. Said curve is commonly referred to as an "AM-PM" trace. A curve 104 illustrates the magnitude of the output energy versus that of the input energy during a sinusoidal input. Said curve is commonly referred to as an "AM-AM" trace. Curve 102 illustrates that the phase of the output energy versus that of the input energy is non-constant over most of the operating region of a conventional non-linear power amplifier. Similarly, the curve 104 illustrates that the magnitude of the energy output is non-linear near a saturation region 106. In the case of the power amplifier illustrated in Figure 1, the saturation region 106 starts at approximately - 4 dBm. It would be apparent to any person skilled in the art that the saturation region may extend over a different range of values. Another point besides simply testing the response or otherwise, characterizing an element of the communication system such as an energy amplifier, is the selection of the energy levels during the operation. In this situation, it would be convenient to have a more precise measurement of the operation, which could be used once a system is deployed or is in use, to occasionally characterize at least its operation and make adjustments to the operation of non-linear devices. .

SUMMARY OF THE INVENTION Accordingly and in view of the above and, of other problems that have been discovered in the art, it is a purpose of the present invention to provide a new technique for accurately characterizing the impact of non-linear devices on signals that they are processed in a spectrum diffusion communication system. For example, the new technique can correctly determine the effects or correlation of the energy level against the decrease in orthogonality in the power amplifiers. These and other purposes, advantages and objects, are realized in a new method of test or characterization of response of apparatuses, such as power amplifiers or other components used to manufacture a communication system of diffusion of spectrum, or complete communication systems. The new method transfers signals within an input to an apparatus or system under test, which are properly routed using a series or group of preselected orthogonal codes. That is, an input communication signal is generated having a series of separate "traffic" channel signals, each of the information or data signals representing, covered or channeled by an individual orthogonal code. In one embodiment, Walsh functions are preferably used as orthogonal codes. Each of the channels are supplied with some type of data or information that will be transferred, except for one or more pre-selected channels. The number of empty channels is based on a degree of orthogonality that will be measured. The data can be randomly generated or selected from a variety of signals or samples of known tests. Preferably, the active channels, use the same level or gain of general input energy and, the data ranges and general content are reasonably similar. The resulting channel signals are combined or multidirected in a CDMA communication signal, which is transferred through the apparatus or system to be tested and the energy measured according to the channel.

In one aspect of the present invention, this is effected by determining which data symbols were transmitted using correlation elements or apparatuses and, measuring a sum of energies for each of the received symbols, using accumulators and adjustment elements, except for empty channels where energy is accumulated. The measured values are used to determine the amount of energy per channel and in the general signal.

Between the sum of energy detected through all "non-empty" or active channels and the "empty" or desired inactive channel, a relation is formed. A relationship is formed more adequately, from the energy in the empty channel and the average energy in the non-empty channels, to more accurately count the number of channels that are being used. This relationship provides an idea of what percentage of energy has changed within the empty channel and, the approximate impact of gain on the purity of the output code and, a measure of the degree to which it is orthogonally degraded by the non-linear response of the device under proof. The sum of energies is divided by the number of channels used to generate an energy density which is then used to form the desired relationship. The method of the present invention can be carried out, using apparatuses constructed as the equipment dedicated to the test, which contains a transmission section and a reception section for testing, in a CDMA signal environment, a non-linear apparatus during Its performance. A power amplifier or similar device that will be tested is typically connected to another circuit with which it could operate normally. In other modalities, a test CDMA communication signal is injected or applied to a section, circuit or transmission elements, within the base stations or input and output circuits that have many data channels. That is, the data intended to transfer over mule separation channels created using the orthogonal codes and, one or more channels without data (empty). At least one receiver receives and demodulates this communication signal and estimates the energy in each channel. These energy measurements are subsequently used to form the Walsh Energy Ratio (WPR), of the energy density in empty channels, versus that of full or active channels. In additional aspects of the present invention, this technique can be used to test portions of an integrated communication system, when in operation. That is, adequate test signals can be transferred during maintenance periods or periods of non-use, to perform measurements and characterize the current response of the system. Alternatively, the fixed (and blank) pattern signals may be transferred through the blank system interspersed with typical traffic channel signals to test the system at periodic intervals or other times, as desired. This allows obtaining information regarding the response of the system in real time, as well as adjusting the operation of power amplifiers in satellites or other devices to provide improved operation and system capacity.

BRIEF DESCRIPTION OF THE DRAWINGS The features, objects and advantages of the present invention will become more apparent from the detailed description set forth below, once taken in conjunction with the drawings in which the reference representations are identified as element, wherein: Figure 1 shows the response of a conventional non-linear amplifier against the output energy; Figure 2 shows a schematic view of an example of the wireless communication system; Figure 3 shows a block diagram of a transmission stage for an input and output circuit; Figure 4 shows a block diagram of a user terminal; Figure 5 shows a block diagram of a signal coding and diffusion apparatus useful in the terminal of the user of Figure 4; Figure 6 shows a block diagram of a conventional communication signal transfer scheme; Figures 7 and 7b show representative input and output waveforms, in a WPR measurement scheme; Figures 8 and 8b show representative input and output waveforms, in a corresponding NPR measurement scheme; and Figure 9 shows a block diagram of the discovered apparatus which is useful for implementing a WPR measurement scheme.

Detailed Description of the Preferred Modalities The present invention is a method and apparatus for determining more precisely the operating characteristics of the non-linear signal that processes elements used in a spectrum broadcast communication system. More specifically, the present invention utilizes a Walsh Energy Ratio, to accurately characterize the impact of nonlinear effects on the operation of the system or component, to enable improved control over the operation of non-linear stages such as high-power amplifiers. power in an orthogonal CDMA communication system. The present invention is particularly suitable for use with high power amplifiers, used in CDMA satellite communication systems. However, as may be apparent to those skilled in the relevant art, the present invention can also be applied to other types of communication systems where devices or components operating with non-linear characteristics are used. Before discussing the embodiments of the present invention, a typical environment is presented in which the present invention can operate. The preferred embodiment of the present invention is mentioned in detail below. Although specific stages, configurations and distributions are mentioned, it should be clear that this is done for illustrative purposes only. An expert in the relevant art will recognize that other stages, configurations and distributions may be used, without departing from the spirit and scope of the present invention. The present invention could discover its use in a variety of wireless communication and information systems. EXEMPLARY OPERATING ENVIRONMENT Figure 2 shows an example of a wireless communication system, such as a wireless telephone system, in which it is discovered that the present invention is useful. The communication system 200 shown in Figure 2 uses broadcast code multiple access spectrum (CDMA) broadcast communication signals, orthogonally encoded, in communication between a remote communication system or mobile terminals or circuit entry and exit of the system or base stations. In the part of the communication system shown in Figure 2, a base station 212 and two satellites 214 and 215, and two associated circuits or cubes 224 and 226, are shown for communication with two mobile stations or user terminals 220 and 222. Normally, base stations and satellites / input and output circuits are components of separate communication systems, referred to as being land based or satellite based, although this condition is not necessary. The total number of base stations, input and output circuits and satellites in such systems depends on the capacity of the desired system and other factors well known in the art. The circuits 224 and 226 and the base station 212 can be used as part of one or two way communication systems or simply to transfer messages or data to the user terminals 220 and 222. Each of the mobile stations or terminals of the user 220 and 222, has or comprises a wireless communication device such as, but not limited to, a cellular telephone, a data transmitter or transfer apparatus (e.g., computers, personal data assistants, facsimile), or a pager or position determination receiver. Normally said units are either portable or mounted in a vehicle, as desired, but fixed units or other types of terminals may also be used where remote wireless service is desired. This last type of service is particularly suitable for use on satellite repeaters to establish communication links in many remote areas of the world.

For this example it is contemplated that satellites 214 and 216 provide directed multiple rays to generally cover geographic regions without overlapping. Generally, multiple rays at different frequencies, also referred to as CDMA channels or 'sub-rays' or FDMA signals, can be directed to overlap in the same region. However, it is easily understood that the lightning coverage or service areas for different satellites or base stations may overlap completely or partially in a given region, depending on the design of the communication system, type of service being offered and the diversity of space that will be achieved. For example, each can provide service to different user groups with different characteristics at different frequencies, or a mobile unit can use multiple frequencies and / or multiple service providers, each with overlapping geophysical coverage. In Figure 1, some paths of possible communication signals that are being established between user terminals 220 and 222 and base station 212 or, via satellites 214 and 216, for one or more input circuits and are shown are illustrated. output or centralized cubes 224 and 226. The user portions of the base station of the communication links between the base station 212 and the user terminals 220 and 222, are illustrated by the lines 230 and 232 respectively. Satellite user portions of the communication links between input and output circuits 224 and 226 and user terminals 220 and 222 through satellite 214, are illustrated by lines 234 and 236 respectively. The satellite user portions of the communication links between circuits 224 and 226 and user terminals 220 and 222, via satellite 216, are illustrated by lines 238 and 240 respectively. The portions of the satellite per input and output circuit of these communication links are illustrated by a series of lines 242, 244, 246 and 248. The dates in these lines show exemplary signal addresses for each communication link, and whether it is either a forward or reverse link, and are only for purposes of clarity and not as an indication of any of the actual signal patterns or physical constraints. The communication system that generally uses multiple satellites 214 and 216 crossing different orbit planes and a variety of Lower Earth Orbits (OTI) and other multiple satellite communication systems, have been proposed to service a large number of user terminals. Those skilled in the art will readily understand how the teachings of the present invention are applicable to a variety of satellite or terrestrial communication systems. The terms base station and input and output circuits are sometimes used interchangeably in the art, with input and output circuits being perceived as specialized base stations that direct communications through satellites, although base stations use terrestrial antennas for direct communications within a surrounding geographical region. User terminals are sometimes referred to as subscriber units, mobile units, mobile stations or in some communication systems simply as "user", "mobile" or "subscriber" stations, depending on how they are preferred. As mentioned above, each base station or input and output circuit transmits a 'pilot' signal throughout an entire coverage region. For satellite systems, this signal is transferred within each satellite 'beam' and originates with the input and output circuits that are being served by the satellite. A simple pilot signal is usually transmitted by each input and output circuit or base station, for each satellite ray frequency to the user. This pilot signal is formed by all users who receive signals from said beam. This technique allows many traffic channels or transporters of user signals to share a common pilot signal for the reference of the conveyor phase. The pilot signals use the same pair of PN broadcast codes or code sets, throughout the communication system, but with different synchronization offsets of the relative code for each beam, element or sector. Alternatively, different PN diffusion codes (generator polynominals) are used among some base stations. In satellite communication systems, groups of different PN codes can be assigned to be used within each orbit plane. This provides signal isolation or reduces interference and allows the rays to be distinguished from each other quickly. Each communication system design specifies the distribution of PN broadcast codes and synchronization offsets within the system according to the factors included in the art. In Figure 3, an exemplary design for a transmission portion or portion of the base station or input and output circuit apparatus used to implement a CDMA communication system is shown. In a typical input and output circuit, some of said sections or transmission systems are used to provide service to many user terminals at the same time, and for several satellites and beams at any time. The number of transmission sections used by the input and output circuit is determined by factors well known in the art, including the complexity of the system, number of satellites under observation, capacity of the subscriber, degree of diversity chosen, etc. Each communication system design also specifies the number of antennas available for the transmission sections to be used in transfer signals. In Figure 3, an exemplary transmitter 300 is shown for use at the user terminals 220 and 222. A transmitter 300 uses at least one antenna 310 to receive the communication signals that were transferred to an analog receiver 314, where they are covered in descending form, amplified and digitized. Normally a bidirectional element 312 is used to allow the same antenna to serve both the transmission and reception functions. The output of the digital communication signals by means of the analog receiver 314 were transferred to at least one digital data receiver 316A and to at least one search receiver 318. The additional digital data receivers 316B-316N can be used. to obtain desired levels of a variety of signals, depending on the acceptable level of complexity of the unit, as will be apparent to those skilled in the relevant art. At least one control processor 320 is coupled to the digital data receivers 316A-316N together with the search receiver 318. The control processor 320 provides, among other functions, basic signal processing, synchronization, power and control or coordination of transmission. Another basic control function that is often performed by the control processor 320 is the selection or manipulation of PN code sequences or orthogonal functions, which will be used for the processing of the waveforms of the communication signal. The signal processing of the control processor 320 may include the determination of the resistance of the relative signal and the computation of several related signal parameters. In some embodiments, the computerization of the signal strength may include the use of an additional or separate circuit, such as a received energy element 321, to provide increased efficiency or speed in the measurements or an improved location of the control processing sources. Outputs for digital data receivers 316A-316N, are coupled to the circuit of the digital baseband 322, inside the user's terminal. The user's digital baseband circuit 322 comprises processing and presentation elements used to transfer information to and from a user terminal. That is, data or signal storage elements, such as long-term or transient digital memory; entry and exit devices, such as display screens, loud voices, terminals, auxiliary keypads and handset; A / D elements, voice coders and other speech and analog signal processing elements; etc., all forming part of the user's base band circuit, which uses elements well known in the art. If signal diversity processing is employed, the user digital baseband circuit 322 may comprise a diversity decoder and combiner. Some of these elements may also operate under the control of or in communication with the control processor 320. When the voice or other data is prepared as an output message or as communication signals originating with the user terminal, the The user's digital baseband circuit 322 is used to receive, store, process and otherwise retrieve the desired data for transmission. The user digital baseband circuit 322 provides this data to a transmit modulator 326 that operates under the control of the control processor 320. The analog receiver 314 may provide an output indicating the power or energy in the received signals . Alternatively, the received energy element 321, can determine this value, by the sample of an analog receiver output 314 and the processing performance well known in the art. This information can be used directly by means of the transmission power amplifier 330 or by the transmission power controller 328, to adjust the energy of the signals transmitted by the user terminal. This information can also be used by the control processor 320. The digital receivers 316A-316N and the search receiver 318 are configured with the signal correlation elements to demodulate and drag the specific signals. The search receiver 318 is used to search the pilot signals, while the digital receivers 316A-N are used to demodulate other signals (traffic) associated with the detected pilot signals. Therefore, the outputs of these units can be monitored to determine the energy in the pilot signal or other signals from the shared source. Here, this is achieved using either the received energy element 321 or the control processor 320. In Figure 4, an example of a transmitting and receiving apparatus 400 is shown, for use in the input and output circuits 224 and 226. The portion of the input and output circuit 224 illustrated in Figure 4 has one or more analog receivers 414, connected to an antenna 410 to receive communication signals where they are subsequently covered in descending, amplified and digitized form, using several well-known schemes in art. The antennas 410 are used in some communication systems. The output of the digitized signals by means of the analog receiver 414, are provided as inputs for at least one digital receiver module, indicated by dotted lines generally at 424. Each digital receiver module 424, corresponds to signal processing elements, used to direct communications between a user terminate 22 and an input and output circuit 224, although certain variations are well known in the art. An analog receiver 414 can provide inputs for many digital receiver modules 424 and a number of said modules are normally used in the input and output circuits 224 and 226 to accommodate all satellite beams and possible diversity mode signals that are being handled at any time. Each digital receiver module 424 has one or more digital data receivers 416 and a search receiver 418. The search receiver 418 generally searches for appropriate diversity modes of signals other than the pilot signals. When they are implanted in the communication system, the multiple digital data receivers 416A-416N are used for the reception of signal diversity. The outputs of the digital data receivers 416 are provided for the processing elements of the subsequent baseband 422, which comprises an apparatus well known in the art and which is not illustrated in more detail in the present invention. Exemplary baseband apparatus includes diversity combiners and decoders to combine multiple path signals within an output for each user. The example baseband apparatus also includes interface circuits to provide output data, typically for a digital switch or network. A variety of other known elements, such as, but not limited to, voice coders, data modems and the interruption of digital data and storage components, can be part of the baseband processing elements 422. These elements operate to control or direct the transfer of data signals to one or more transmission modules 434. The signals will be transmitted to the terminals of the users, are coupled to one or more appropriate transmission modules 434. A typical input and output circuit , uses a number of said transmission modules 434 to provide service to several terminals 222 at the same time and, for several satellites and beams at the same time. The number of transmission modules 434 used by the input and output circuits 224 is determined by factors well known in the art, including the complexity of the system, number of satellites under observation, user capacity, degree of diversity chosen and the like. Each transmission module 434 includes a transmission modulator 426, which modulates data with broadcast spectrum for transmission. The transmit modulator 426 has an output coupled to a digital transmit power controller 428, which controls the transmit power used for the outgoing digital signal. The transmit power controller 428 applies a minimum energy level for purposes of interference reduction and source distribution, but applies appropriate levels of power when necessary to compensate for attenuation in the transmission path and other transfer characteristics of the transmitter. trajectory. A PN 432 generator is used by the transmission modulator 426 in the signal diffusion. This code generation can also form a functional part of one or more control processors or storage elements used in the input and output circuit 224 or 226. The output of the transmit power controller 428 is transferred to an adder 436, where it is added with the outputs of the other transmission power control circuits. Those outputs are signals to transmit to other user terminals 220 and 222 on the same frequency and within the same beam as the output of the transmit power controller 428. The output of the adder 436 is provided to an analog transmitter 438 for the conversion from digital to analogue, conversion for the frequency of the appropriate RF carrier, in addition to the amplification and output to one or more antennas 430 for radiating to the user terminals 220 and 222. The antennas 410 and 430, can be the same antennas depending on of the complexity and configuration of the system. At least one control processor of the input and output circuit 420 is coupled to receiver modules 424, transmission modules 434, and baseband circuit 422; these units can be physically separated one from the other. The control processor provides command and control signals to perform functions such as, but not limited to, signal processing, signal synchronization generation, energy control, control transmission, diversity combination, and system intrusion. In addition, the control processor allocates PN broadcast codes, orthogonal code sequences, and specific transmitters and receivers for use in user communications. The control processor 420 also controls the generation and energy of the pilot, synchronization and location channel signals and their coupling to the transmit power controller 428. The pilot channel is simply a signal that is not modulated by the data and I could use a constant value or tone type input for the transmit modulator 426, effectively transmitting only the PN diffusion codes applied from the generated PN 432. Although the control processor 420 can be coupled directly to the elements of a module , such as transmission module 424 or reception module 434, each module generally comprises a module specific processor, such as a transmission processor 430 or reception processor 421, which controls the elements of said module. Therefore, in a preferred embodiment, the control processor 420 is coupled to the transmission processor 430 and the reception processor 421, as shown in Figure 4. In this way the simple control processor 420 can control more efficiently the operations of a large number of modules and sources. The transmitter processor 430 controls the generation of, and signal energy for, pilot, synchronization, location and traffic channel signals and their respective coupling to the power controller 428. The reception processor 421 controls the search, of PN broadcast codes for demodulation and monitoring of received energy. As described above, a received energy element can be used to detect the energy in a signal, monitoring the energy at the outputs of the digital data receivers. This energy information is provided by controlling transmission energy to adjust the output power to compensate for large changes in path attenuation. Therefore, these elements are part of an energy control feedback loop. This energy information may also be provided to a reception processor or control processor, as desired. Part of the energy control function can also be incorporated into the reception processor. For shared source power control, an input and output circuit receives information about the received signal resistance or about the signal to noise ratio, from the user's terminals in the communication signals. This information can be derived from the demodulated outputs of the data receivers by the reception processors; or alternatively, this information can be detected as it happens in the predefined locations in the signals that are being monitored by the control processor or reception processors and transferred to the control processor. The control processor uses this information to control the amount of energy used for the shared source signals, using transmission power controllers. Limitations and Energy Control One of the key disadvantages in a satellite communication system is that it severely limits the amount of energy available on the satellite during signal transmission. For this reason, the strength of the signal of each traffic signal is individually controlled to minimize the energy consumed by the satellite, while maintaining an acceptable traffic signal quality. But when the signal strength of a shared source signal is controlled, such as a pilot signal, all users who share the source, should be considered collectively. For satellite repeater systems, the pilot signal is transferred within each satellite ray frequency and originates with the input and output circuits according to the satellite or satellite beam that is being used for the communication links. However, pilot signals can also be transmitted as shared sources to various combinations of rays and sub-rays, using a variety of satellites, input and output circuits or base stations, as will be apparent to one of skill in the relevant art. The teachings of the present invention are not limited to a specific pilot transmission scheme in a communications system, nor by the type of shared source that is being used. Normally, each pilot signal within a communications system is generated using the same PN code with different code synchronization offsets. Alternatively, each pilot signal can be generated using a different PN code. This provides signals that can be easily distinguished from each other, while providing simplified acquisition and tracking. Other signals are used to transmit the modulated spectrum broadcast information, such as input and output circuit identification, system synchronization, subscriber locator information and various other control signals. As previously stated, the amount of energy available for signal transmission is limited in a satellite communications system, by the power generation capacity of the satellite (s). To optimize the use of this energy, it must be carefully distributed between traffic signals and pilot signals. If there is very little energy that is distributed to the pilot signal, the user's terminals can not accumulate enough energy to synchronize their receivers with the input and output circuit. Conversely, if too much pilot signal energy is transmitted, the amount of energy available for the traffic signals is reduced, and therefore the number of users that can be supported. Therefore, to maximize the capacity of the subscriber in the satellite, the amount of pilot signal energy transmitted must be precisely controlled. One method to solve this problem is the open circuit pilot signal energy control. In this method, the input and output circuit makes an open circuit estimate of the trajectory gained in the forward link, for example, from the modulator in the input and output circuit, through the satellite answering machine, to the terminal of the user. The input and output circuit uses this estimate to control the pilot signal energy transmitted by the input and output circuit, therefore, to control the energy of the pilot signal transmitted by the satellite answering machine. A significant problem with this method is that this open-circuit estimate will contain errors due to uncertainties in the path gain, including uncertainties in the electronic gain of the satellite answering machine, gain compression of the high-power answering amplifiers. of the satellite, antenna gain and path loss due to atmospheric effects such as rain attenuation. The error due to these uncertainties in profit can be very long. Signal processing In Figure 5, an example of the design of the signal modulator to implement the transmit modulator 426 is shown in greater detail. The modulator 426 would include one or more blank encoders and interceptors (not shown) for coding. , such as by circumvolutional coding, with repetition and blank intercalation data symbols, in order to provide error detection and correction functions. Techniques for circumvolutional blank coding, repetition and intercalation are well known in the art, as are other techniques for the preparation of digital data for transmission. The teachings of the present invention are not limited by the pre-broadcast digital data preparation method. Subsequently, the data symbols are encoded or covered orthogonally with an assigned orthogonal code, here a Walsh code Wn, supplied by a code generator 502. The code generator 502, can be constructed using a variety of known elements configured for this purpose The generator code 502 is multiplied by or combined in another way with, the symbol data using one or more logical elements 504. The range of the orthogonal code chip, as well as the encoded data, is determined by factors well known to the experts in art. The transmission modulator circuit also includes one or more broadcast sequences or code generators 506, which generate two different PNi and PNQ broadcast codes for the In-Phase (I) and Quadrature (Q) channels, respectively. This generator could be time shared between several transmitters, using appropriate interface elements. An exemplary generation circuit for these sequences was described in US Patent No. 5,228,054 entitled "Two-Length Pseudo-Noise Sequence Generator Energy with Fast Displacement Adjustments", issued July 13, 1993. Alternatively, the PN codes can be stored previously in the memory elements, such as a ROM or RAM circuit, such as in the form of look-up tables with automatic sorting or addressing, as is known.The broadcast code generator 506, it also typically responds to at least one input signal, corresponding to a beam identification signal or control processor element which provides a predetermined time delay or offset for the output of the PN broadcast codes, as appropriate Although only the PN generator is shown for the diffusion codes, it is easy to understand that others can be implanted rios PN generator schemes, using few or several generators. The orthogonally encoded symbol data is multiplied by the PNi and PNQ broadcast codes, using a pair of logical elements or multipliers 508A and 508β. The same data is the input to both multipliers and is subject to modulation with or modulation by the individual codes. In some proposed communication systems, broadcast codes are applied or used in a layer configuration. That is, a short period upper range code is used as a basic 'inner' encoder to spread in a conventional manner and a second lower period lower range code that is synchronized with the first code, is used as a code 'outside' to help in the identification and acquisition of the signal. This multi-level broadcast distribution improves the signal acquisition process, as explained in the pending US Patent Application SN 09 /, (will be assigned), entitled "Dissemination of the Multiple Layer PN Code in a Communications System of Multiple Users ", issued on October 10, 1997. Figure 5 shows how the outer sequence codes are applied, using a pair of elements or logical multipliers 510A and 510B, with the code that is being generated by the code generator 512. However, the use of one or two diffusion codes does not seem to have any impact on the signals in terms of changing the amount of bleeding or filtering between channels, due to the intermodulation distortion. Subsequently, the output signals encoded by PN diffusion and orthogonally resulting, are usually band passages filtered or formed by the filters 514A and 514B and, modulated in an RF transporter, normally modulating by means of a bi-phase a pair of sinusoidal squares that are summed within a simple communication signal, using a addition element or aggregator 524. This is shown by the sinusoidal inputs to a pair of multipliers 520A and 520B, which each receive one of the signals filtered from the filters 514A and 514B, respectively. However, it will be readily appreciated that other types of modulation can be used within the teachings of the present invention. The source of the carrier signal, such as a local oscillator, is represented by block 522, using circuits and apparatuses well known in the art. The above devices and processes are also used to generate pilot signals except that there is generally uncoded data or interleaved in white that will be processed. Instead of this, a constant level signal is covered with a unique code, which is a dedicated Walsh code and is subsequently broadcast using logical elements 508A, 508B, 510A and 510B. When desired, the data in the form of a repeating pattern could also be used to formulate a pilot signal. The pilot signal is also normally provided with more energy when it is processed by the transmitted power controller 428 and the analog transmitter 438, to ensure although this is not required, adequate power to ensure reception, even in the lightning strips. Once modulated in the RF transporter (522), the pilot signal is transferred within each ray, or CDMA channel, served by the input and output circuit, as desired. Non-Linear Processes After the coverage or channeling (Wn) and the previous PNP-Terrestrial PNP propagation occurs), the resulting output is provided to a High Power Amplifier (HPA). Additional amplification using an HPA occurs before the signal is transferred by air, either directly to the intended signal vessels from a base station, or from an input and output circuit via the satellite link. In addition, some user signals are, as mentioned above, summed together to form a communication signal as well as for a beam or element, and subsequently scaled prior to power amplification. This process is illustrated in the left part of Figure 6. In Figure 6, only the Walsh coding logic for the channels through the Wn channels is shown, using 6020 coding elements through the 602N- coding elements. I, here presented as multipliers, to combine the input data with the appropriate Walsh function. However, other logical or processing elements may be used for this combination as desired. The diffusion and other elements are not shown for purposes of clarity. The coded or channeled signals are summed together in a sum or signal combiner element 604, and provided for an adjustable gain or attenuation element 606, just before the input to a high power amplifier 608, which could be to be found, for example, in the analog transmitter 438. The final stage of the amplifier shown by the figures, could find use in the input and output circuits, the base stations, or even in the satellites, to provide a final gain in the energy level of transmitted signals. Subsequently, the amplified energy signals are transmitted to the communication system 200, to the user or user terminals (224, 226) through a channel 610, where they are received and demodulated, using an apparatus such as analog receivers and digital (316, 416), mentioned above. Channel 610 is usually an air interface used by the input and output circuits, base stations and satellites, to transfer wireless signals. However, the present invention is also applicable for CDMA channels carried by other means such as wires and optical cables. As is well known in the art, each user terminal applies one or more appropriate broadcast codes (PN, PN, ntepor, PNextepor), during the demodulation process so as not to broadcast the signal (not shown). The undistributed communication signal is then combined with a function or orthogonal code, here the desired Walsh code sequence (W,? _), Used by the user terminal to retrieve signals in a particular code channel. That is, the user terminal employs a preselected code a, or assigned to retrieve information or data that is being directed to the user's terminal, using the known logical elements. In Figure 6, the appropriate Walsh code is multiplied by the undistributed input data symbols, using a multiplier 612. The results are accumulated in an accumulator or accumulation element and sum 614, and energy is integrated into the periods pre-selected, in order to generate or recapture the underlying data in the received communication signal. That is, a sum of amplitudes of the symbol is formed in the accumulator to determine the energy in each channel. This process is well known in the art and discussed in greater detail by way of example, in the North American Patent No. 5,577,025. The resulting cumulative values can be squared to provide absolute values. To determine when the signal has made a transition between -1 and 1 as used in the communication signals, a hard limiter 616 is often used. As stated above, the presence of intermodulation distortion or non-linear effects in Several stages of high power amplification, used in a communication system, provide little security for the adjustment, control and predictable operation of the system or amplifiers. Without proper adjustment and control, these nonlinear elements cause the transfer of undesirable energy from a traffic or user channel to another performance of the degradation system. Previous techniques for testing system components that depend on well-known measures such as NPR have an unacceptable inaccuracy proven in the actual prediction or performance component of the system. This results in a lack of ability to properly configure or adjust the system and minimize the impact of intermodulation distortion. Therefore, a new technique has been developed to improve the operation of CDMA communication systems. Walsh Energy Ratio The new technique is used to test or monitor the performance of nonlinear system components, under realistic signal conditions to provide a more accurate prediction of component or device performance in an O-CDMA signal environment. The data signals are transferred in an input to an apparatus or system under test, which are appropriately piped using a series or group of codes from Wo to WN-I and subsequently summed together. That is, a generated input communication signal comprises a series of separate "traffic" channel signals, each representing information or data signals covered or channeled by an individual orthogonal code. Here, Walsh functions are used as orthogonal codes, although this is not strictly required in the present invention. Each of the channels have some type of data or information that is being transferred, except for one or more preselected 'p' channels, represented here by the Walsh Wp function. The number of empty channels is determined by the degree of orthogonality that will be measured. For example, as mentioned below, the multiple channels may be used to provide additional information on how the orthogonality is being affected through a communication link as a whole or to provide an indication of channel-by-channel quality. The data used in the active or 'non-empty' channels may be generated randomly in the use of a known process or mode, or selected from a variety of known test signals or samples. Preferably, the transfer data of active channels, use the same level or gain of general input energy, although it is not strictly required and the data ranges and general content are reasonably similar. The blank or "no data" traffic channel does not have a data entry for which it corresponds to the Walsh function code. The signal CDMA or SS combined or multidirected, is subsequently scaled as desired, and transferred through the apparatus under test and energy is measured according to or for each channel. Generally this is done by determining which data symbols were transmitted and forming a sum of energies for each of the symbols received in a channel to determine the amount of energy per channel. Ideally, a channel should show zero energy, since the data was not transmitted. However, due to the effects mentioned above, a part of the energy will be detected or measured in the "empty" channel. In Figures 7a and 7b, the effect of this process is shown. In Figure 7a, a representative communication signal 702 is shown, having a series of traffic channels 704 containing information to be transferred and a channel 706 having the data that will not be transferred. Since this is not required in the art, data channels that are not illustrated as having the same energy can also be applied to systems during actual use. In the above situation, not all channels will have identical power or power levels, for example due to several power control situations for different users, or to the impact of the channel on the received signals. In Figure 7b, a representative received signal is shown, which shows that due to the effects mentioned above, part of the energy has been filtered within the corresponding channel 706, that is, the orthogonality through the channels has not been maintained. In Figures 8a and 8b, a similar process is shown in which the development of tests or NPR analysis is used. In Figure 8a, a representative communication 802 is shown, which has a signal with energy or information, otherwise, continuous frequency bands 804, occupied by the traffic signals, except for a small spectrum channel or band 806, It does not have data or information, therefore, the energy that will be transmitted. A representative received signal is shown in Figure 8b, which shows that due to several previously mentioned effects, part of the energy has been filtered in the corresponding spectrum band 806. Using the present invention, a relation between the sum is formed of energy detected through the "non-empty" or active channels and the "empty" or inactive channel. A measure of the energy ratio in the empty channel for the rest of the channels provides an idea that the percentage of energy has changed within the empty channel and the approximate gain impact on the purity of the code output. This relationship provides a measure of the degree, which is orthogonally degraded by the non-linear response of the apparatus or system under test. That is, a measure of the degree to which the channels are no longer isolated from one another. To achieve this, a sum of energies is formed for the symbols received for all "non-empty" channels in the communication signal in general. Subsequently a relationship is formed, using the energy detected in the "empty" channel, from forming a sum for each channel as mentioned above and this last sum of energy for the "non-empty" channels. The energy in the empty channel is usually accumulated over a preselected period, such as some periods of Walsh code or data symbols and then averaged to produce a desired energy density measure for the channel, since there are no data symbols but only the noise that is being measured in this situation. The technique of the present invention can be carried out using a variety of known apparatuses. For example, a specialized piece of test equipment can be constructed containing a known O-CDMA type signal generation circuit and a transmitter or transmission section to generate the desired communication signals, a mechanism for coupling the signals to an apparatus non-linear under test and a receiving section that uses known circuit elements to receive the communication signal and form the sums of desired energies through the channels. This allows testing a non-linear device for its performance or the impact of non-linear processes in a CDMA environment. An apparatus such as a high power amplifier can be connected in a normal way to another circuit, with which it would operate normally. In Figure 9, an embodiment of the apparatus useful for implementing the process of the present invention is shown. As in the case of Figure 6, only an example Walsh coding logic is shown, said apparatus being well known, for the data channels from W0 to WN-I using the coding elements from 6020 to 602N.- | The diffusion and other elements are not shown for clarity purposes. In Figure 9, the data signals from the year to the an-? they are transferred as inputs to logic or coding elements from 602th to 602N-I, here represented as multipliers with other known logic or processing elements, used as desired. The data signals are combined with individual functions W¡L Walsh (i goes from 0 to N-1), where L represents the length of the code or sequence, to produce covered or coded data. The coded or channeled signals are added together again in summarizing element 604, to form a CDMA communication signal (multiple channel) and provided for an adjustable gain or attenuation element 606, just before it enters the apparatus, component or 902 high power system, under test. The device could find use in input and output circuits, base stations or even in satellites. The amplified energy signals are subsequently transferred to a series of decoding or demodulation stages on the chosen interface (air) or channel to where they are received and decoded (not shown without diffusion). During this process, the communication signal is combined with each function or orthogonal code, here the desired Walsh code sequence (W¡L), used by all active or non-empty channels, or by the active user terminals or channels of code, to transfer signals or information. That is, a group of preselected or assigned codes are applied to recover the information or data that is being transferred by means of the communication signal, using the logic elements. 'L' represents the length of the code sequence. Preferably, the codes for all active or used channels, which are employed in this operation, the code for the empty channel is also used at this point to allow the recovery or measurement of the energy content of said channel.

In Figure 9, the appropriate Walsh codes are multiplied by the undistributed data symbols of input, using a series of multipliers 904¡L (904OL-904N-IL). The results are accumulated in an accumulator or in addition and accumulation elements 906¡ (906O-906N-I) as indicated above. A normalization factor of 1 / N can be applied as shown, although this is not required for several applications. The accumulated energy or sums generated in the accumulators 906¡ (9060-906N-.), Each one is subjected to a square operation, using elements or means of elevation squared. Most of this is useful when working with other complex signals valued or with those that have negative as well as positive amplitudes (-1, 1) against a simple binary. The resulting squared signals are then used to form an average energy density value for all active or "non-empty" channels, using an average computer averaging element or averager 910. That is, the quantity or quantity of energy received for each of the active channels, is added or aggregated together and divided by the number of channels involved in the calculation to form an average energy value for the active channels. This average value or energy density for the non-empty channels is subsequently transferred as an input to a relationship determining element 912, which also receives a magnitude value for each of the empty channels that are being used during the try, here the single channel "p". However, the use of additional channels or other empty channels may provide useful information as will be indicated below. The values or average density of empty and non-empty energy are subsequently used to form the desired WPR measurement ratio.

This relationship can be used as an indication of the degree to which the apparatus under test is impacting the orthogonality or isolation of the channel for communication signals in the system. This allows a designator or system tester to more accurately determine the impact of particular components, devices or systems, and the impact any adjustments made to those devices will have. This new technique is especially useful in the testing of components during communication applications such as cellular communication systems from one to several forward links CDMA, PCS, local wireless circuit (WLL), via satellite LEO. This new technique can be used in at least two modes to improve the operation of a CDMA spectrum broadcast communication system. In one method, the individual parts used to manufacture the system can be tested in the apparatus of Figure 9, or using other known apparatuses, to see how they will perform in the CDMA communication channel environment. According to this method, it has been demonstrated that the energy control techniques used in CDMA communication systems achieve improved results by having the ability to have greater accuracy in the account of certain characteristics of predictable or known system components. , involved in their respective measures. In a second method, this technique can be used to test portions of the communication system itself, either before being put into service or when it is in operation. For example, during specified maintenance periods or periods of non-use, the signals may be transferred to communication system 200, user or user terminals (224, 226) through portions of the system, such as particular base stations , input and output circuits or satellites to perform the measurements and characterize the current response of the system, or of certain system components. A preselected CDMA test signal is injected or applied to the transmission section of an input and output circuit, with many channels 'ascending' or occupied with data and one or more channels 'descending' or empty. Subsequently, a dedicated receiver demodulates the signal and estimates the energy in each channel for use in the computation or measurement of the Walsh Energy Ratio (WPR), which is the ratio of the energy density in empty channels to the full channels. This receiver can be placed in a user terminal, used only for said test and located in an input and output circuit or in an area served by a communication system, or within one or more terminals of the user, such as fixed terminals . In some configurations the WPR measurement may occur in one or more user terminals, not dedicated specifically to this task, in response to commands received from an input and output circuit, using known receivers and control processors. The resulting information is communicated back to an input and output circuit and / or returned to a location of the central security system for use in the additional signal processing, including various measures of energy control and level adjustments. An alternative embodiment is to provide the test communication signal (multiple channel), such as presenting multiple data channels or intentional data for different code channels (user terminals) to transfer, through the baseband circuit in the base station or input and output circuit, at periodic intervals to automatically check the status of, or changes in, the operating characteristics of certain components. For example, this is useful for checking changes in operating characteristics for HPAs located on satellites, which may experience, over time, certain changes in their non-linear characteristics, in response to changes in load, or when in an ascending energizing operation mode, as is known. Using the present technique, the measurements can be used during the use of the system to count harmful effects, found otherwise due to some of these conditions. In another embodiment, the signals that contain fixed and blank data or do not contain data in some channels, can be transferred through the system interleaved in white with typical data in the traffic channel signals, to test the system in intervals newspapers, or other times as desired. This allows obtaining information regarding the response of the system in real time and adjusting the operation of power amplifiers in satellites or other devices to provide improved operation and system capacity. That is, the commands can be sent to control elements that adjust certain thresholds and operating ranges for said components, to provide improved control and output behavior. As stated above, multiple channels that contain data or that are empty may be used for the process of the present invention. That is, more than one channel may not have data applied in the formation of a multi-channel communication signal. This can be used to analyze any difference in the orthogonality or loss thereof (energy transfer) between the channels. Non-linear effects can affect a coded channel more than others, or other processes may be occurring that believe that there is this impact. Therefore, this is useful for having the ability to allocate multiple empty channels and compare the WPR for each of the channels, in the form of a classification of the "quality" indicator of the channel. The use of a simple WPR for a single channel indicates the impact on the performance of the system in general, while the multiple channels indicate the performance of the relative channel or other relative impact between the channels, and therefore, the merit of using certain channels. Nevertheless, it may be useful to form an average WPR through said multiple empty channels. This can provide additional information It has been found that where there is a limited set of M channels (with chip 64 that are common for cellular systems and chip 128 for satellite systems) and N outside M that are being used, there are naturally some combinations for which a group of channels that form N is more beneficial than another. Similar, in terms of WPR measured, to having good and bad combinations of N. Speaking of M channels, each of them can be blanked or flushed of data, one at a time, and a WPR measured very quickly for each channel. The resulting group of WPR values can be used to develop a metric to show the "best" relative channels, to be used for the possibilities N outside M. That is, the channels or combinations that provide at least the loss of orthogonality. This process can also be carried out, taking multiple empty channels at the same time, as desired, to develop an additional metric, about which combinations work best. This information can be used to tailor the assignment of codes or channels, according to the determined operating conditions, or to a group of devices, components or specific operating equipment. Some other embodiments of the present invention may have the advantage of the multiple vacuum channel feature. For example, since a standard or relative degree of orthogonality maintenance can now be measured or observed, one can recognize that another empty channel can provide one communication function or communication link better than the other, according to certain operating conditions. The relative differences in WPR across multiple empty channels can be used as a measure of the relative performance of a channel. Channels or groups of channels can be scanned periodically in a communication system, to observe the "best" channel before the assignment of new codes / channels to system users. Therefore, the relative differences in WPR across multiple empty channels can be used as a basis to decide what will be used next time. That is, either intentionally for the test or as part of a natural occurrence of the multiple channels that are being released during the use of a communication system, each of these empty channels is tested and the resulting WPR used to select a channel for assignment in the next access request or to adjust a channel or communication link. In this way, the WPR becomes a very effective tool for the allocation of channels to achieve the best communication links for system users. At the same time, this allocation allows a more efficient use of energy through the channels.

This also provides a communication system or the input and output circuits and base stations, to observe the changes during the operation, including those observed during the length of the links or "calls" of real communication. If some channels seem to be more problematic or are likely to have more problems with the orthogonality that is being maintained, then they are less desirable for use. This also applies to the effects manifested during active calls. That is, a communication system controller, base station or input and output circuit may be warned of some channels that are less likely to provide high quality links, including when a channel changes. In this situation, a call or communication link can be changed out of another coded channel that uses several soft transmission techniques, without breaking the connection to speak. Therefore, a call or link can be better managed and an improved link quality can be maintained. Although the information available from having the WPR measures is useful for the general improvement of direct energy control, other advantages can be realized. Using the WPR, such as through the comparison of pre-selected thresholds or even dynamically adjustable thresholds, a decision can be made not only as to whether or not the energy should be increased or decreased, but whether the channels additional fees should or should not be allocated. That is, the energy can also be adjusted by simply not allowing the capacity of a particular beam or element to increase. Therefore, channels are not assigned to new communication links or users, until the conditions are improved.

Although a solution to improve the WPR is clearly to reduce the energy to avoid reaching or reaching above the saturation level for some devices or components, or to reduce the load of the system, reducing the number of users, there is usually a most important answer. That is, the test can indicate an appropriate form in which the hardware used to transfer signals is constructed and configured, and many adjustments can be made during the fabrication and testing of a communication system or its components. However, once the system is in operation, the test or monitoring method of the invention will indicate that the system is not working as planned. That is, a system failure to accommodate the full anticipated load (capacity) and the estimated energy output. This is not simply a matter of simple energy adjustment, but in many cases an indication that a component is not operating according to any guidelines and needs to be fixed. This information can be used to decide when to send personnel to provide additional diagnostic services or services with respect to the equipment, in the input and output circuits and base stations, and to mechanically replace or adjust the components to improve the operation. The present invention aids in such determinations. The above description of the preferred embodiments is provided to enable any person skilled in the art to make or use the present invention. The different modifications for these modalities will be easily apparent to those skilled in the art, and the generic principles defined in the present invention can be applied to other modalities, without the use of the faculty of invention. Therefore, the present invention is not intended to be limited to the modalities shown therein, but it is to be in accordance with the broad scope consistent with the new principles and features described herein.

Claims

R E I V I N D I C A C I O N S Having described the present invention, it is considered as a novelty and, therefore, the content of the following CLAIMS is claimed as property:

1. A method for determining the response of a spectrum diffusion communication system or one or more devices used therein for non-linear purposes, which comprises the steps of: generating a plurality of orthogonal channel signals which are each channelized using one of a set of previously selected orthogonal keys, each of the channels having the data being transferred, unless one or more previously selected channels are inactive; generating a spectrum broadcast communication signal which comprises a combination of two or more of said plurality of information signals, at least one being inactive, which are broadcast using one or more PN diffusion keys previously determined; transfer a spectrum broadcast communication signal through the system whose response will be determined. measuring the amount of energy present in each signal channel that is being used by said spectrum broadcast communication signal including said inactive channel; and generating a ratio of the energy in at least one inactive channel to the average energy detected in all active channels, to provide a measure of the degree to which the orthogonality is degraded.

2. The method as described in Claim 1, further characterized in that the data comprises randomly generated data.

3. The method as described in Claim 1, further characterized in that the data comprises samples of previously selected test data.

4. The method as described in Claim 1, further characterized in that the active channels use the same level or gain of general input power.

5. The method as described in Claim 1, further characterized in that an inactive channel is used.

6. The method as described in Claim 1, further characterized in that two or more inactive channels are used.

7. The method as described in Claim 1, further characterized in that the orthogonal functions are Walsh functions.

8. The method as described in Claim 1, further characterized in that it further comprises the transfer of said spectrum broadcast communication signal through a satellite communication system.

9. The method as described in Claim 8, further characterized in that it comprises the transfer of said spectrum broadcast communication signal through a satellite communication system during the periods of operation.

10. The method as described in Claim 1, further characterized in that it comprises the transfer of said spectrum broadcast communication signal in a previously selected periodic base through a portion of said communication system.

11. The method as described in Claim 1, further characterized in that it additionally comprises the data transfer that is actually attempted for system users interleaved in white with the data that is attempted to prove an energy ratio for channels in said signal spectrum diffusion communication.

12. A method of selecting one or more channels for use in a spectrum broadcast communication system, which comprises the steps of: generating a plurality of orthogonal channel signals which are each channelized using one of a set of orthogonal keys previously selected, each of the channels having the data that is being transferred, unless one or more previously selected channels are inactive; generating a spectrum broadcast communication signal which comprises a combination of two or more of said plurality of information signals, at least one of which is inactive, which are broadcast using one or more PN diffusion keys previously determined; transfer a spectrum broadcast communication signal through the system whose response will be determined. measuring the amount of energy present in each signal channel that is being used by said spectrum broadcast communication signal including said inactive channel; generate a ratio of the energy in at least one inactive channel to the average energy detected in all active channels, to provide a measure of the degree to which the orthogonality is degraded; and selecting at least one channel to be used based on said relationship.

13. The method as described in Claim 12, which comprises the steps of: generating a ratio of the energy in a plurality of inactive channels to the average energy detected in all active channels; and selecting at least one channel to be used based on said relationship.

14. The method as described in Claim 12, further characterized in that it comprises the step of selecting a set of channels to be used.

15. The method as described in Claim 12, further characterized in that it comprises the steps of: generating a ratio of the energy in one or several inactive channels to the average energy detected in all the active channels; and repeat the generation step of relation for each of the inactive channels; and selecting at least one channel to be used based on said relationship.

16. The method as described in Claim 12, further characterized in that it further comprises the step of joining one or more lists of channel sets to use them based on said relationship.

17. The method as described in Claim 12, further characterized in that it further comprises the step of indicating to the operators of the system a deficient condition for the channels that are being used within the communication system.

18. An apparatus for determining the response of a broadcasting communication system of the spectrum or of one or more apparatuses used therein for the non-linear effects, which comprises: means for generating a plurality of orthogonal channel signals which are channeled each one using one of a set of previously selected orthogonal keys, each of the channels having the data that is being transferred, except that one or more previously selected channels are inactive; means for generating a spectrum broadcast communication signal which comprises a combination of two or more of said plurality of information signals, at least one being inactive, which are broadcast using one or more PN diffusion keys previously determined; means for transferring a spectrum broadcast communication signal through the system whose response is to be determined. means for measuring the amount of energy present in each signal channel that is being used by said spectrum broadcast communication signal including said inactive channel; and means for generating an energy ratio in at least one inactive channel to the average energy detected in all active channels, to provide a measure of the degree to which the orthogonality is degraded.

19. The apparatus as described in Claim 18, further characterized in that said apparatuses are located within a satellite communication system.

20. The apparatus as described in Claim 18, further characterized in that said apparatuses comprise High Power Amplifier Systems (HPA) located on satellites.

21. The apparatus as described in Claim 18, further characterized in that said apparatuses comprise High Power Amplifier Systems (HPA) located in input and output circuits.

22. The apparatus as described in Claim 18, further characterized in that the data comprises samples of previously selected test data.

23. The apparatus as described in Claim 18, further characterized in that the active channels use the same level or gain of general input power.

24. Apparatus for selecting one or more channels for use in a spectrum broadcast communication system, which comprises the steps of: means for generating a plurality of orthogonal channel signals which are each channelized using one of a set of orthogonal keys previously selected, each of the channels having the data that is being transferred, unless one or more previously selected channels are inactive; means for generating a spectrum broadcast communication signal which comprises a combination of two or more of said plurality of information signals, at least one being inactive, which are broadcast using one or more PN diffusion keys previously determined; means for transferring a spectrum broadcast communication signal through the system whose response is to be determined. means for measuring the amount of energy present in each signal channel that is being used by said spectrum broadcast communication signal including said inactive channel; means for generating a ratio of the energy in at least one inactive channel to the average energy detected in all active channels, to provide a measure of the degree to which the orthogonality is degraded; and means for selecting at least one channel to be used based on said relationship.