CN1572079A - Method and device for data communication in a multi-user system - Google Patents

Abstract

A communications method and device that enables multiple source devices (110, 120, 130) to communicate information to a destination device (100) is disclosed. The information communicated from any source device to the destination device (100) typically takes the form of binary electronic product codes ('EPC') or identification ('ID') information. The preferred embodiment of the invention utilizes the techniques of: data scrambling and descrambling; channel selection and transmission; enabling and disabling group transmissions; correlation; and collision mitigation.

Description

Be used for method and apparatus in the multi-user system data communication

The application relates to following US application, and these applications and the application have for motorola inc jointly:

Sequence number 09/981,031, people such as Gurney submitted in October 17 calendar year 2001, and name is called " Channel Selection Method Used in a Communication System " (attorney docket CM01960G);

Sequence number 09/978,890, people such as Kuhlman submitted in October 17 calendar year 2001, and name is called " A Method of Scrambling and Descrambling Data in aCommunication System " (attorney docket CM01962G);

Sequence number 09/982,271, people such as Gurney submitted in October 17 calendar year 2001, and name is called " A Correlation Method used in a Communication System andApparatus " (attorney docket CM01968G);

Sequence number 09/982,279, people such as Kuffner submitted in October 17 calendar year 2001, and name is called " Collision Mitigation Methods used in a Communication System " (attorney docket CM01969G);

Sequence number 09/981,476, people such as Collins submitted in October 17 calendar year 2001, and name is called " Method and Device for Enabling and Disabling GroupTransmissions " (attorney docket IND10254).

Invention field

The present invention relates generally to a kind of method and apparatus that is used in the multi-user system data communication.

Background of invention

For many application, wish in multi-user system, to have a kind of method that fast, effectively also reliably transmits data.When a receiver need read multiple segment data (from multiple source) fast, just need such method.A concrete application of such technology is in many clauses and subclauses electronic recognition.

Electronic recognition industry is very important for many commerce and Military Application, and these application comprise real-time item tracking and stock.Use can increase operating efficiency greatly so in many cases, and in fact these situations comprise that all relate to the situation of the manufacturing of certain form, warehouse-in, distribution and retail.The ability of inventory tracking in real time carried out accurately fast and effectively can reduce the waste of many forms greatly, includes but not limited to misplacing of article, the overstock of article or the short supply of stock, and article stealing.

Current, electronic recognition industry is main to rely on manually (based on light) scanning to discern a plurality of article, and wherein each article has distributed a product code.Currently in whole kus kretail industry, be extensive use of Universial Product Code (UPC) system.But the manual scanning article expend time in and have been easy to human error very much.

Therefore, need provide a kind of method that is used for effectively and fast sending to a receiver data from multiple source.

Brief Description Of Drawings

Referring now to accompanying drawing, only the present invention is described by example, similarly reference marker is represented similar elements in the accompanying drawings, wherein:

The general view that Fig. 1 explanation multiple source device according to the present invention is communicated by letter with a single destination device;

Fig. 2 explanation is according to the present invention, and how the data that are stored on the label when operation are changed and are used to determine communication channel;

Fig. 3 explanation is used for according to the present invention to the general view of the processing of the data scrambling of being stored on the label;

The general system view of the many label communications that Fig. 4 explanation is carried out in reader according to the present invention and the inverse process (de-scrambling method) of scrambling;

Fig. 5 explanation is according to the iterative algorithm that is used for scrambling and recovers label data of the present invention;

The specific example that Fig. 6 explanation is handled according to scrambling of the present invention;

Fig. 7 explanation is according to the general block diagram of label of the present invention;

Fig. 8 illustrates that summary sends the general flow figure of condition according to label of the present invention;

Fig. 9 illustrates that summary sends the detail flowchart of condition according to label of the present invention;

Figure 10 explanation is used capacity coupled application between reader and various label in an exemplary embodiments according to the present invention;

Figure 11 explanation is according to the present invention, based on the method for the channel that is stored in the data generation transmission label on the label;

Figure 12 illustrates that one is simplified the tag circuit functional block diagram, emphasizes correlation and modulator approach according to each journey of the present invention;

Figure 13 explanation is according to the detailed view of reader block diagram of the present invention;

Figure 14 explanation is according to the example that is used for the fast transform approach of Walsh code signal of the present invention;

The specific example that Figure 15 explanation reader receiver signal that is used for pseudo random sequence fast correlation according to the present invention is handled;

The simplification functional block diagram that Figure 16 explanation is handled according to reader signal of the present invention;

Figure 17 explanation is the example waveform when having conflict according to the present invention;

Figure 18 explanation is the several example waveform when not having conflict according to the present invention;

Figure 19 explanation is according to the general flow figure of reader action of the present invention;

Conflict alleviates the detail flowchart of the reader processes signal of (forward collisionmitigation) technology according to use forward direction of the present invention for Figure 20 explanation.

Figure 21 explanation is not exemplary stock's management of application collision mitigation technique according to the present invention;

The example flow diagram of Figure 22 explanation inventory algorithms when application collision mitigation technique not according to the present invention;

Figure 23 explanation is according to the exemplary stock's management with conflict mitigation technique of the present invention;

Figure 24 explanation is according to the exemplary stock's management with two-way conflict mitigation technique of the present invention.

Embodiment

The invention discloses a kind of improved communication means, this method makes the quick also transmission information effectively of multiple source device give an order device.Described communication system adopts the combination of several technology to realize being better than the performance of prior art.The invention provides a kind of device that is used to replace UPC, and increase extra characteristics and benefit, such as manually (based on light) scanning of cancellation, and scanning (or item recognition) speed that improves greatly.Identification when the present invention further provides numerous items, this is in many application, such as all very useful in stock, retail checkout or the like.

The preferred embodiments of the present invention general using one-way communication is so that simplify the circuit of source apparatus; Source apparatus does not need to use receiver.

The information that is sent to destination device from source apparatus typically adopts the form of binary system electronic product code (" EPC ") or identification (ID) information, but this is not by any way to the restriction of these message forms.Also may transmit other types information, such as electronic remote detection (or the standard of any other type or specific data).In fact, the present invention can use any information of representing with the binary digit form.

As shown in Figure 1, this information typically is sent to a single destination device 100 from one group of source apparatus 110,120,130; The preferred embodiments of the present invention transmit when utilizing information from this group source apparatus 110,120,130 to this destination device 100.Because the present invention has many application, therefore according to the context of example, for easy explanation, some terms that use in whole discussion can be replaced mutually with other terms.Therefore, it is noted that in the discussion below whole, below these terms that exchange to use have no lack of generality: source apparatus, transponder, user, project project, label or the like; These exchange the term that uses and have no lack of generality below also it is noted that in the discussion below whole: destination device, system controller, interrogator, reader, receiver or the like.

The communication system that the present invention adopts comprises several different communication form 140, includes, but is not limited to optical communication, radio frequency (RF) communication, wired (contact) communication, capacitive coupling communication, or inductance coupling high communication.The preferred embodiments of the present invention are used the capacitive coupling communication link between label 110,120,130 and reader 100, but also can unrestrictedly utilize other communication link form.

Below detailed description of the present invention be divided into five major parts and the decline that the system operation example is provided, the critical aspects of major part descriptive system.All key technologies that the preferred embodiments of the present invention utilization describes below, but other embodiment also can only utilize a subclass of institute's description technique.

I. data scrambling and descrambling

As shown in Figure 2, the data 200 that are sent to reader 100 from label 110 in described system can adopt many forms, include, but is not limited to standard described below or other user definition data.In a preferred embodiment of the invention, the data 200 of transmission are made up of at least one recognition data sequence.For example, data 200 can be made up of at least one EPC, EPC has the recognition data of 96 bits, and the recognition data of this 96 bit is described in the article of David L.Brock " The Electronic Product Code " at MIT-Auto ID center in January calendar year 2001.EPC200 is by retain header 203, target classification 204, producer's code 206 and sequence number 206 these several fields, is used for each label (or project project) 110 in the recognition system uniquely.Notice that for example, the information of 96 bits provides unique ID (2 of tremendous amount ⁹⁶～8 * 10 ²⁸Huge for this numeral is described, to give one example, the quality of the earth is 6 * 10 ²⁷Gram).

In a preferred embodiment, on the data 200 of being stored on the label, typically add additional information 202, such as user profile, error detection or error correction information (for example, forward error correction (FEC), Cyclic Redundancy Check or the like) and other reservation bits.Note, add this additional information (for example, error detection or error correction data) before or after the data scrambling that also can be described below is handled, still,, wish that also it has even stochastic behaviour if after data scrambling, add additional information.

One skilled in the art would recognize that and on label 110,120,130, to be scheduled to and the information of storing several different additional form (for example, programmable time mark, other individual subscriber identifiers (PIN), normal data, environmental data or the like).Notice that in described system, the data volume or the data type that are stored on the label 110,120,130 are unrestricted.

All label functions typically use low complex degree (for example, low cost) circuit to realize.In order to make the circuit 110 on the label simple, and can (describe) for the channel selectivity in the raising system comprehensively, wish before initial ID data 200 are stored on the label 110 especially its scrambling as following institute.This is typically by handling 211 and realize storage being carried out a randomization or scrambling before label 110.

In whole system, typically use this scrambling algorithm 211, after scrambling, 220 show the statistical property (promptly evenly at random) of expectation so that guarantee EPC data 200.As selection, in other embodiments, can use some other scrambling to the data of being stored 200, encrypt or the numbering assignment algorithm, so that produce scrambled data 220 effectively.In order to realize the privacy of additional information, each producer can selectively use pre-encryption 210.

Fig. 3 explanation is used for the data 220 of scrambling are embedded into the example of the system of label 110 according to a preferred embodiment of the invention.In Fig. 3, from EPC keeper 310, for example manufacturer obtains initial EPC200 with usual way.Then EPC200 is input in the scrambler 330, this scrambler 330 is carried out the data (S_EPC) 220 of a scrambling algorithm and output scrambling.A RF label programmable device/write device 350 is the data of scrambling then, and promptly S_EPC is embedded in the label 110.As the modification of primary data 200, the data 220 of scrambling are present in the label 110 now.

The general block diagram of electronic recognition data 200 is read in Fig. 4 explanation simultaneously from many RF label apparatus 110,120,130.This example illustrated how to read during the typical stock control be placed on shelf on the label that is associated of product.In operation, reader 100 activates one group of label 110,120,130 simultaneously.Multipass transmission algorithm (multiple-pass transmission algorithm) (describing in detail) is carried out on the basis that the label 110,120,130 that is activated then uses the data 220 of this scrambling to select as channel in part III.

For example, in first journey (a first pass) of multipass algorithm, use at least a portion (it is embedded in the label 110) of EPC1 to come selective channel A240, use at least a portion of EPC2 to come selective channel B240, and use at least a portion of EPCn to come selective channel C240.Should be noted that channel A, B and C or their combination in any can be identical or different.Reader 100 is proceeded its demodulating algorithm, and finally obtains the S_EPC220 of the label 110,120,130 on the shelf.S_EPC220 is sent in the descrambler 460, and this descrambler is carried out a Descrambling Algorithms, to obtain the initial EPC data 200 of label 110,120,130.Can be kept in the reader 100 or send back to initial EPC keeper 310 (for example manufacturer) corresponding to the EPC data 200 of each label with the form of inventory report.One skilled in the art would recognize that descrambling operation can be other local execution, such as the computer or the line server of long-range setting.Conflict in Fig. 4 system is minimized, because during every journey of multipass transmission algorithm, label 110,120,130 is not to use highly organized EPC data 200, and is to use at least a portion of the scrambling form 220 of EPC data to select a channel.The data 220 of scrambling are very similar to even distributed data, thereby the conflict that has between the product of similar EPC data 200 just can be minimized.For more contents of multipass transmission algorithm and signal selection, referring to following part III; For more contents, referring to following part of V about conflict and anti-collision.

Need to select before a channel is used for sending exchange message (being described below) not between label 110 and reader 100 at label 110.Therefore scrambling of the present invention and de-scrambling method must be (self-refertial) that refers to certainly; Just, the information of scrambling EPC200 and descrambling S_EPC220 only is these data itself.

Described in the present invention system need use a kind of method for scrambling, and this method comprises certain key characteristic.A key property is that this method for scrambling is mapped as the result who shows even random distribution nature to typical data sequence (such as the EPC data sequence).In a preferred embodiment, method for scrambling has two key properties:

1. the typical EPC200 of given two k units (k-ary) digitized representation, here k be the integer be scheduled to (for example, in a pair of typical EPC200, many but not every k unit numeral is identical), the probability that mates corresponding to scrambling S_EPC220 and n the continuous k unit numeral of these EPC200 (being used for determining channel allocation by label 110) approximately is 1/k ⁿAnd

2. given two typical EPC200 with k unit digitized representation, here k be the integer be scheduled to (for example, in a pair of typical EPC200, the first numeral of many but not every k is identical), its scrambling output and n continuous k unit numeral (being used for determining channel allocation by label 110) coupling, the probability that m subsequently k unit numeral (being used for determining subsequently channel allocation by label 110) mated approximately is 1/k ^m

In the example of the EPC200 of binary representation, these characteristics are relevant with strong avalanche characteristic, depend on each input bit and change a single input bit by each output bit of this characteristic, change the output bit of half on an average.

The present invention carries out this scrambling and de-scrambling method by using in the division of the recurrence strategy shown in Fig. 5 and overcoming this problem.This scrambling algorithm 510 receives data and length information as input and recursively to a left side and the right half scrambling of these data.Descrambling Algorithms 520 is carried out the inverse function of scrambling algorithm 510.As follows to all operations except basic (at last) level of recurrence:

For method for scrambling 510:

1. one group of data is divided into first and second portion;

2. the first to these group data carries out the first scrambling algorithm, with the first of the scrambling that produces these data;

3. revise the second portion of these group data with the first of the scrambling of these group data, revise second portion to produce of this group data;

4. the modification second portion of these group data is carried out one second scrambling algorithm, to produce a scrambling second portion of these group data; And

5. revise the scrambling first of these group data with the scrambling second portion of these group data.

For de-scrambling method 520:

1. one group of data is divided into a first and a second portion;

2. revise the first of these group data with the second portion of these group data, to produce a modification first of these group data;

3. the second portion of these group data is carried out one first de-scrambling method, to produce a descrambling second portion of these group data;

4. revise the descrambling second portion of these group data with the modification first of these group data, to produce a modification second portion of these group data;

5. the modification first to these group data carries out one second de-scrambling method.

In superincumbent scrambling 510 and descrambling 520 methods, modify steps be reversible and be from add by XOR (XOR), modulus, modulus subtracts or the like the group of forming and selects.In addition, first and second scramblings/de-scrambling method difference is execution in step 1 to 5 recursively, up to being reached predetermined length by these group data of scrambling/descrambling, this means and must set up a base case.In the preferred embodiment, predetermined length is a byte.

In case these group data reach predetermined length, just carry out a predetermined function.This predefined function is reversible, and preferably one search function; In a preferred embodiment, carry out a replacement box (" S-box ") and search function.Stop to be good a byte, because to by dividing and overcome data bit scrambling/descrambling that technology separates than using one to search function efficient is lower significantly simply.Stop to cause the big and heaviness of S-box table to be difficult to use in bigger quantity by meeting.

Predefined function in the present invention has the characteristic of many requirements.At first, this function should be reversible.Scrambling algorithm 510 uses S-box to search function, and de-scrambling method 520 uses S-box to search the inverse function of function; This function need be reversible, so that can find initial EPC200.In actual conditions, for the reversible function of searching, each clauses and subclauses (entry) should accurately occur once.In the present invention, the input of S-box is that a byte and output also are bytes.S-box and it contrary each all comprise the data of 256 bytes.

Second characteristic of predefined function is that it will show strong snowslide criterion; Just each output bit depends on each input bit.An additional characteristic, just so-called strict snowslide criterion (" SAC ") be, changing the possibility that an input bit just in time makes each output bit change is 50%.This characteristic is not strict the needs for the present invention, though it does not have harm.

At last, predefined function shows low dpmax.The value of dpmax is the XOR matrix discal patch purpose maximum of look-up table.In the XOR matrix (i, j) clauses and subclauses are the quantity of 0＜α＜256, so that make f (α) ^f (α ^i)=j, f is a look-up table here.When this table was used iteration, low dpmax characteristic can provide continuous good mixing, and this is a basic scheme of the present invention.Usually seek such look-up table in cryptography.For example in Advanced Encryption Standard (" AES ") cryptographic algorithm, use the table that almost satisfies SAC, and such table should be suitable for also in the present invention.If AES also is used for and incoherent other systemic-function of the use described in the present invention, reuses this table and can save code space.

Fig. 6 explanation expands into the block diagram of the scrambling processing of discrete parts.At the described embodiment of Fig. 6, the input of this processing is the EPC data 200 of 128 bits (or 16 bytes).EPC data 200 are segmented and label is byte P ₀To P ₁₅Scrambling (or descrambling) is handled and is begun leftmost two byte (P on Fig. 6 upper left side ₁₄To P ₁₅) be input to " MixBytes " piece 610." MixBytes " piece 610 by the S-box that is designated as " S " search function 602 and 608 and the xor operation 606 and 604 that is designated as ' ' form.Below this block diagram, next procedure is XOR 624 ensuing two byte (P ₁₂To P ₁₃) and the output of " MixBytes " piece 610.This algorithm is by using XOR function 622,626,628,632,634,636,642,644,646,648,652,656 and 658 continuous data splittings and use function 620,630,640,650,660,670 and 680 mix bytes and proceeds, and output byte 220 (C grade occur up in the end ₀To C ₁₅).According to the preferred embodiment, entire process needs the xor operation of 16 S-box search operations and 64 times one bytes.

Outside above-mentioned scrambling is handled, data 200 can also be before using the common scrambling algorithm encrypted 210 (for example, before) to label 110 programmings so that further guarantee safety of data.There are various known cryptographic algorithm (for example, AES, data encryption standard, IDEA or the like) can be used for this task in the art.Can use additional safe level for highly confidential application very important (for example, label may comprise responsive medical science or financial data).

II. powering method

The block diagram of the label 110 in Fig. 7 in the spirit of explanation preferred embodiment.For a capacitive coupled system, antenna 701 is pair of conductive electrode (for example, the electric capacity paster), but also can be any method that an electromagnetic field energy is coupled to a circuit usually.The rectification in power converter 703 of variable current in the reader 100 (" AC ") power, wherein this reader 100 is coupled to this label 110, the direct current of power converter (" DC ") output is used to drive label 110 and plays tag energy monitor 704, this monitor 704 further can communicate by letter (its element is discussed below in more detail).State controller 705 acts on label data 220 and communication channel is selected piece 240, to produce emission information, this emission information is applied in the radiated element 702 (for example, the load-modulate element of fine understanding) in the art under the control of channel modulator 708.

The data 220 that are stored on each label 110 are typically stored in low complex degree (that is, the low cost) circuit, and it can respond the inquiry from reader 100.According to the present invention, each label 110,120,130 is typically waited for one first predetermined condition that will satisfy before its information of emission in a multipass algorithm.For each label 110,120,130, this first predetermined condition typically is set to identical, but also can select arbitrarily or specify in other embodiments.Figure 8 illustrates the example that the expression label sends the general flow figure of condition.Note, in this flow chart, can be by various measurements when first predetermined condition or second predetermined condition (for example, when no longer) second predetermined condition.

In the preferred embodiment, reader 100 long-range driving labels 110,120,130, and when the power level in label 110 instantaneous receptions surpasses a predetermined threshold (it is determined by 703 and 704 usually), satisfy the first transmission condition.Fig. 9 illustrates the flow chart of this process, and wherein T1 and T2 represent first and first power level threshold.Notice that those skilled in the art also can use the realization of adopting other predetermined conditions (for example, specific lock-out pulse or pseudorandom pause) and not break away from spirit of the present invention.In case label 110 receives driving (is from remote reader 100 for passive label, and be self-driven for active tag), label 110 monitors the signal strength signal intensity that receives continuously, begins emission so that determine when.In case label 110 begins its data is modulated and launched 250, it is just activated fully.Notice that in the preferred embodiment of this system, a plurality of labels 110,120,130 are typically activated fully a preset time.

The label that is activated fully in this group will continue their information of emission in a plurality of journeys (comprehensively describing below), and up to satisfied second predetermined transmission condition, during this time they just stop to launch data.When label monitor 704 is observed when the power level of label 110 receptions is lower than first predetermined threshold or surpasses second predetermined threshold, satisfy the second predetermined transmission condition in a preferred embodiment, wherein second predetermined threshold typically is set to be higher than first predetermined threshold.

By this way, the first and second predetermined transmission conditions form a received power level scope (for example, a window), and in this scope, every group of label typically activated fully.In a preferred embodiment of the invention, approximately 3dB is wide typically for the scope that powers on, the power of label 110,120,130 responses just in 1-2X scope (receiving the operand power level with respect to certain standardization).Notice that this power window makes the emission of label drop in the proportional narrow power window usually, the typical near-far problem of this some communication system (for example, in having the spread spectrum system of nonopiate spreading code) that can help to weaken the effect.

In a preferred embodiment, all label 110,120, the 130 typically designated same scopes that power in the system, but also may be other embodiment, for example utilize (for example, preassignment, but possibility difference) able to programme or the condition that powers on arbitrarily.Certain differentiation (or difference) is provided between for the product in different manufacturers, during the different manufacturers designated different scope that powers on level, such example will occurs.

In other embodiment of described system, can there be label with two-way communications capabilities, in this case, the first and second predetermined transmission conditions can be made up of certain type lock-out pulse or other signaling information.Arbitrarily in the situation, they can determined arbitrarily on the label 110 or during the programming of label 110 in predetermined transmission condition.Noting, also can be that other is realized the mode (for example, synchronizing signal is with label two-way communication or the like) of these transmission controls and does not break away from spirit of the present invention.

In an exemplary embodiment illustrated in fig. 10, reader 100 is connected to through a transmission medium 1003 on the antenna 1004 that is installed on the shelf 1005, and wherein this reader 100 can be by controller 1001 by parent company's Long-distance Control.The object 1020,1021,1022 of different physical sizes has the label 110,120,130 that is positioned on the packing different piece, and can be variant during coupling between antenna 1004 relevant and the antenna 701 relevant, and the power level difference that further causes label electronics 1012 to receive with label 110,120,130 with reader 100.Because the reader antenna 1004 in the system is different with the coupled characteristic of various labels 110,120,130, for a given reader antenna level of drive (being the reader transmitted power level), different labels may receive different power level (by range limit 1030 and 1031 expressions).In a preferred embodiment, this effect also plays the total number of labels that exists in the rough minimizing system, because each label 110,120,130 may begin emission at different reader transmitted power levels and the different time that causes thus.Notice that in a preferred embodiment of the invention, for a certain power level, a plurality of labels 110,120,130 still typically begin emission simultaneously.For example, in a stock, there are 1,000 clauses and subclauses (label) to need identification, and reader 100 can ten different power capability level of saltus step, can activate group's (still, can activate less label at high and utmost point low-power level) of about 100 labels in each power level.In another embodiment of the present invention, for example, the emission from a plurality of labels in the user selects that a specific time slot launches time-division (channelizing) system may be (but synchronously not necessarily) by synchronously.Notice that in one embodiment, reader 100 is with all possible power level of saltus step.Like this, because the certain power scope of label 110,120,130, so reader 100 can be controlled every group of label effectively and when begins and finishes to launch.This respect is very important, because when reader 100 can determine all labels 110,120,130 in the certain power scope by unique identification, it can step to next power level (for example, about 1031) or stop identifying this time.

In another embodiment, the scope of the expectation power level of given stock's configuration file can " be learnt " or remember to reader 100, and have the priority that activates historical power level for its power scan configuration awards these.As following further described, when reader 100 steps to the power level that can not activate any label, it can sense this situation (typically measuring by an of short duration energy or modulation detection), and step to next power level apace, so that minimize total reading times of label.

III. channel is selected and launching technique

Do as the present invention, all multi-sources (or multi-user) communication means uses certain type channelizing method.May utilize in the present invention several channelizing methods and any one of technology.Usually, the channelizing method that the present invention utilized can be divided into two classes, orthogonal channel method or accurate orthogonal channel method.

The quadrature communication channel has the following advantages, and promptly in a linear system (that is, the cross-correlation between different channels is defined as zero), communication can not disturbed (at all) communication on one other channel on the channel of a selection.Accurate orthogonal channel is near quadrature (that is, for the cross correlation value of different channels near zero), and typically utilizes this scheme in direct sequence CDMA (DS-CDMA) system, and each user is typically specified a different spreading code in this system.

Well-known in this area, known maximum length linear feedback shift register (" LFSR ") sequence (that is m sequence) has low (that is accurate quadrature) their cross correlation.The cross correlation value of two nonopiate sequences is defined as-1/N (standardization), and N is the length of LFSR pseudo noise (" PN ") sequence here.In code division multiple access system, the different code of identical basic m sequence is used to the different user of channelizing usually.Each symbol and bit are typically referred to as one " chip " in the PN sequence, and this is known in the art.

Some examples of orthogonal channel function include, but is not limited to the Walsh function, the time slot in time-division system, the frequency in a frequency division systems, specific lengthening PN sign indicating number or the like.Some examples of accurate orthogonal channel function comprise aforesaid m sequence or PN sequence.

The example of a specific lengthening PN sign indicating number is such, it has one manually (promptly, be not that normal running by LFSR is produced) be inserted in this sequence (according to code phases, on the difference in sequence) binary zero, so that aim at the time (promptly, artificial zero appearing in the same time migration of channel of inserting synchronously) is zero thereby cause the cross-correlation between the different code phases of same m sequence.Notice that the preferred embodiments of the present invention are utilized these specific lengthening m sequences (having represented its generation at Figure 11), so that obtain the orthogonal code channel in synchro system.As the benefit that adopts spread spectrum to increase, can also realize anti-interference (be also referred to as and handle or the expansion gain), this is known in the communications field.The Application of Technology is for serious electromagnetic environment like this, and is such as the environment of plant, very important.

As above mentioned, the label 110,120,130 in described system uses their data of multipass transmission algorithm emission.When determining total time for reading of label 110,120,130, the multipass transmission algorithm is very crucial and be made up of several different aspects.The general thoughts that adopts in this algorithm is, each label 110,120,130 will be selected the communication channel of specific (preferably evenly at random) in each algorithm journey.

In the preferred embodiment of described system, channel selects 240 typically directly based on the data 220 that are stored in label 110.In a preferred embodiment, label 110 is its information (that is, recognition data) of emission on selected channel typically, until next journey of algorithm, at this moment it will be selected a new channel and repeat this process.The emission of label in a preferred embodiment of the invention is assumed to (according to first predetermined condition) approximately synchronously.

The channel of each label is selected based on predetermined information (that is, the programming of the label in exemplary embodiments 230 or may be determined in the design of label itself).In a preferred embodiment of the invention, the channel of each label 110 is selected directly directly to determine (with a kind of algorithmic approach) by the recognition data (as described further below) that is stored on the label 110.It is noted that also that in another embodiment top predetermined information can comprise the number that does not directly produce at random based on being stored in the data on the label 110.

In the above part I an and key of better systems performance, the preferred embodiments of the present invention requirement are comprehensively described, storage 230 before label 110, at least a portion of data 200 (for example, EPC, CRC or the like) is by randomization in advance (or scrambling).Because label 110 must use the data 220 of storage, or its part (for example, 221,222), to select 240 1 communication channels in each journey of multipass algorithm, for the whole system performance of the best, it evenly is vital at random that data 220 show as.This can realize that this algorithm part I has in the above carried out comprehensive description by a reversible scrambling algorithm 211 of low complex degree.

Distinguishingly, as shown in Figure 12, in a preferred embodiment, in each journey of a plurality of transmission journeys, a predetermined subset (for example, 221 of the data 220 of channel selection procedure by utilizing pre-scrambling (be randomization and storage), 222,223,224) in each journey, select communication channel.Channel selector 1220 such as transducer or multiplex machine 1240, is typically selected a channel.A new subclass 221,222,223,224 that is stored in the data on the label 220 (promptly, new random number is extracted) typically be used to algorithm each subsequently the channel in the journey select, can be at random and selective channel independently thereby guarantee in whole multipass transmission algorithm.

Notice that label 110 can send its all data 220 (as in a preferred embodiment) in each algorithm journey, or only sends the part (that is, send enough data usually and determine the channel that label is utilized in next journey) of data.Typically, be used for the data division the 221,222,223, the 224th that channel is selected in each journey of algorithm, unique and be the continuous part of data 220, it is preferably by pre-randomization.The particular channel that is used for each journey of multipass transmission algorithm selects to be called one ' channel selection configuration file '.

For example, in the system with the pre-scrambling recognition data 220 of 128 bits that is stored on each label, but the unique continuous part of 8 bits can be used for selecting 256 (that is, 2 in each journey of 16 (that is, 128/8) algorithm journeys ⁸) in the channel one.Like this, the first randomization byte of the data of each label (for example 221) is selected the communication channel of 240 each label respectively in first journey of algorithm, second (and wishing different) byte of the randomization data of each label (for example 222) is used to select 240 transmission channels in second journey of algorithm.This pilosity send journey to handle and proceeds, and uses up and (for example, finishes the 16th journey in this embodiment up to being stored in all data on the label; In Fig. 2, should be corresponding to 224), or reader 100 notified tag stop to send (as mentioned above, usually by coming sensing in label 110 in 704 (1210) second predetermined condition).In case the data of using up, whole process repeats alternatively, but label will typically be selected same (deterministic) channel.Notice that the conflict that must occur for randomization for each label (referring to further describing in detail among the lower part V), is wished to select one at random and well-determined channel for each algorithm journey.

Certainly, other parts (for example, discontinuous or not exclusively unique) that those skilled in the art will recognize that data also can be used to select directly or indirectly the communication channel in each journey.By this way, channel select to repeat and before, in fact may increase the algorithm journey maximum quantity and without limits.Channel selects configuration file (or channel selection algorithm) to make amendment after some transmit journey, like this, different subclass of same data 220 can be used to subsequently channel and select 1220 (in selection that this pattern (pattern) is any to expand unique channel before repeating).For example, after 16 journeys of multipass transmission algorithm, label can be selected data (that is, tentation data) displacement 4 bits (in the above example) to channel, and the new channel that is used for the journey subsequently of this algorithm with arrival is selected data.By this way, may expand the quantity that unique channel selects and have virtually no restriction, but can increase the complexity of tag circuit.

Other embodiment of channel selection algorithm also can use certain type mapping (normally man-to-man look-up table, or other algebraically or logic) function, determine the channel selection according to the data (restricted usually) of storing or being programmed on the label.Unique key that channel is selected to handle is characterised in that, in case certain partial information of relevant data in the known label just can be selected by calculating channel in reader 100.

Because channel resource is limited (that is, in each journey of the multipass communication of algorithms, the number of channels available that each user can select is limited), therefore when sending label, certainly exist conflict.Conflict is defined as, and two or more labels are chosen on the same channel and communicate by letter in a special algorithm journey.This situation is among expecting in normal running.For example, for the situation that a kind of typical 25 labels are communicated by letter on 64 channels, it is 99.6% that each journey has the probability of once conflict at least.This is based on the following fact, and promptly for M the label of communicating by letter on N channel, conflict free probability expression is

Alleviate several numeric example of discussion tag transmits conflict in the method and their means to save the situation in part of V-conflict below.

In many cases, the number of labels in system (at a specific level that powers on) in addition can surpass available channel quantity (especially in preferred embodiment algorithm journey early, or the quantity when available channel as described below be provided with hang down the time).When utilizing the orthogonal channel method, this in the present invention situation can be accepted fully.Notice that typical in this DS-CDMA system (using accurate orthogonal channel sign indicating number) can be considered to overload, and unreliable communication (the further knowledge that especially, does not have the tag transmits feature) can take place.Importantly, in described system, activate number of tags and can further reduce effectively by the conflict mitigation technique, this conflict mitigation technique is described in the part of V below comprehensively.

No less important ground is, the preferred embodiments of the present invention in each journey of multipass transmission algorithm, utilize variable number channel (by by 221,222...224 determines), so that improve performance (for example, total time for reading of whole system, total system capacity, reliability or the like).In other words, the quantity of available channel can be inequality with the number of channels available in another journey of this transmission algorithm in a journey of multipass transmission algorithm.The number of channels available of each algorithm journey (being time per unit) is called the dynamic channel configuration file under discussion, because the quantity of available channel is along with the time dynamically changes.Realize the dynamic channel configuration file in fact optimization total transmitting time of expection number of labels (or total time for reading).

Notice that the transmitting time of each journey of this algorithm typically is proportional to the channel quantity (the channelizing method is irrelevant with utilizing) of that journey that can be used for algorithm.Overall transmission time (the T of multipass transmission algorithm _TX) can be expressed as:

$T_{\mathrm{TX}}=\frac{1}{R}\underset{i=1}{\overset{L}{\mathrm{\Σ}}}{N}_i*B_i$

In the formula, L is the quantity that successfully sends the needed transmission journey of data, and R is transmission (signaling or channel symbol) speed, B _iBe the quantity of each journey data symbol that will send, N _iBe available channel in i journey of algorithm (or expansion gain) quantity.Notice that in a preferred embodiment of the invention, L can equal 16 journeys, B _iBe fixed as 128 bits, R equals 62.5KHz, concrete N _iBe worth given in the above example, but this only is a specific embodiment of this system.Note each journey (N _i) number of channels available depends on usually at each journey (n _i) in be used for selecting the amount of bits of communication channel, concern following (in 240, also showing):

$N_i=2^{n_i}$

In the preferred embodiment of this system, N _iRepresent the spreading gain of every journey and the quantity of available codes phase place, R is to be each second the signaling rate of unit with the chip.Notice that the application of senior conflict mitigation technique (describing) can reduce the required transmission number of passes amount (L) of label 110,120,130 greatly in part of V.Usually, in other embodiment of described system, any value is not limited in the top equation.

Because in above-mentioned preferred embodiment, the transmitting time of each journey (and channel speed) depends on the number of channels available of each journey, therefore by in the channel early of multipass transmission algorithm, using the channel of lesser amt, always read (promptly finishing) time performance (almost not having other benefit for the label of smallest number) because in system, add more channel in this case for what the smallest number label can improve system.In the journey of algorithm back, can increase channel quantity (may in a plurality of steps), so that adapt to the situation that the larger amt label is arranged in system, and reader 100 does not adopt more complicated signal processing (for example, the senior conflict alleviates) technology of mentioning among the lower part V.

By this way, the adverse effect than the longer transmission time of the system of (early) channel selection that the system with lesser amt label typically can not be subjected to having larger amt, and the system that has the larger amt label simultaneously also can obviously not affect adversely (because the early journey of multipass algorithm still typically takies the time of much less, thereby initial number of channels available is less).Also have, the channel that is increased in the algorithm journey of back selects quantity can guarantee that the system with larger amt label can successfully obtain all data (thereby improving system reliability) in the algorithm journey of limited quantity.

For example, the preferred embodiments of the present invention are utilized the data 220 of 128 bits, and in the 1st and the 2nd algorithm journey 32 channels are arranged, and 64 channels are arranged in the 3rd to the 6th algorithm journey, 128 channels are arranged in the 7th and the 8th journey, and in remaining 8 algorithm journey, 1024 channels are arranged.Notice that in this embodiment, unique subclass of data 220 is used to directly to select 1220 communication channels 1260 in each journey, thereby using up unique, the maximum that do not reach 16 algorithm journeys before the lap of data.Other embodiment of the present invention can utilize each transmission algorithm journey that the channel of variable number is arranged, and it is to change after the journey of predetermined quantity.For example, in the above example, first 16 journey of multipass transmission algorithm can be utilized from the available channel of 32-256 (promptly, five to eight bits of channel selection data) any, and ensuing 16 journeys can be utilized available channel from 256-4096 (that is, channel is selected eight to 12 bits of data) any.By this way, dynamic channel configuration file (or number of channels available of each algorithm journey) in fact can be by expansion and without any restriction.The maximum quantity that note that journey once more can utilize the overlapping or cross part of data to assign to the driving data selection algorithm and expand.

In a specific embodiment of system, the actual selection of the number of channels available of each algorithm journey (dynamic channel configuration file) also can depend on the expectation of (except that the existing label anticipated number of system) reader 100 utilizations or the signal processing algorithm (for example, this class conflict alleviates algorithm) of main type.Notice that the number of channels available of each algorithm journey can also cause the channel configuration file to reduce in the journey of back.Usually, any channel configuration file along with time change can be considered to the dynamic channel configuration file for order of the present invention.

Notice that reader 100 does not need to know in advance the channel configuration file of specific label 110, but normally this situation.If channel configuration file the unknown of label 110, reader 100 for example just must be determined the cycle (may by measuring its auto-correlation or spectral characteristic) of PN (chip) sequence, and correspondingly move (demodulation).

Particularly, in a preferred embodiment of the invention, accidental channel selects to be used to select specific spreading code (or 1220 sign indicating number channel) in each journey of multipass transmission algorithm.More specifically, in the preferred embodiment, the part of storing/being programmed in the data 220 on the label 110 is used to directly to determine that specific lengthening m sequence that a length is N (here, as mentioned above, N equals the channel quantity in a specific algorithm journey) time migration (or as at code phase of 1220).Schematically shown this processing at Figure 11.The out of phase of a PN sequence produces one the 3rd code phase of same m sequence usually by a mask function (or AND-XOR simplifies network 1100) of using PN generator (LFSR) state, the mould 2 that this mask function can be carried out two or more m sequences effectively adds.Like this, all labels 110,120,130 use same basic LFSR (m sequence) generator in each algorithm journey, from same initial generator state, all label 110,120,130 transmission just can be a known basic initial generator state synchronously like this in the preferred embodiment.As the description of part of V I below, these aspects in the reader fast and all be crucial in demodulation effectively.Notice that as mentioned above, basic LFSR sequence generator length (that is primitive polynomial) typically dynamically changes (change channel quantity) in each algorithm journey.

In the preferred embodiment, by being forced output 0 the first chip time, traditional m sequence generator is made into specific lengthening PN sequence generator, thereby guarantees that the cross-correlation from the sequence of different labels is zero on the cycle at a given sequence.Note, in time on other aspects, force producing orthogonal sequence (as doing) in one the zero input code sequence at other system, and also can use the orthogonal function generator of other types to replace LFSR PN generator (for example, Walsh or Hadamard function) in other embodiments.Then by conventional apparatus 1230 (for example, known in those skilled in the art, the XOR in digital instrument, or the multiplier in the analog instrument) with the data 220 of spreading code 1260 extension storage on 110 that produce.On given communication channel, send the spread data signal that (with the set form) activates label then.

Notice that label may adopt the demodulation type of a scope to send their data (for example, amplitude modulation(PAM), phase modulated, frequency modulation(FM), or their certain combination).Amplitude offset keying (" ASK ") form in the modulation of the preferred embodiments of the present invention radiated element 702 working loads, but can certainly adopt other modulation type and equipment (for example, differential Quadrature Phase Shift Keying, quadrature amplitude modulation, pulse code modulation, impulse phase modulation or the like).Also can adopt various digital coding and mapping techniques in the present invention.The example of some coding techniquess includes, but not limited to make zero (RZ), non-return-to-zero (NRZ), and Manchester (Manchester), and differential code, these all are well known in the art.Notice that also can use different codings, modulation, coding (coding) and signaling type in the present invention and be no lack of generality, this also is known in the art.The example of some codings (coding) technology comprises the CRC sign indicating number, convolution code, and block code or the like, these also are known in the art.

Label 110,120,130 is also directly modulated the carrier wave that reader 100 provides through radiated element 702 in a preferred embodiment; Like this, they just do not have local oscillator (but the carrier wave that yet may use this locality to produce certainly within the scope of the invention is not the application that limits it by any way).In a preferred embodiment of the invention, power converter 703 rectifications are from the carrier signal of reader 100, so that the circuit of reader 100 on can long-range driving label 110.Note, also can use the active drive label, rather than limit use of the present invention by any way.General objectives of the present invention is the complexity that minimizes label 110, by in operation technique described in the preferred embodiment, keeps the circuit minimized on the label 110.

IV. fast demodulation method

As shown in figure 13, reader 100 is typically by the output of a signal source 1310 of initialization and with certain minimum levels transmitting power, begin the processing of reading of label 110,120,130, wherein this signal source 1310 has launching electrical level control 1320 and amplifier 1330.In the preferred embodiment, reader 100 beginnings are with the continuous waveform of that level emission then.In case this reader 100 is launched with a certain power level, it just typically monitors any signal that (through coupling device 1340 and antenna 1345) returns from label 110,120,130.The form that this activity detection can adopt modulation or energy measuring to measure for example detects signal level or signal swing (this is further described below) in each possible communication channel.Wish to make this measuring period short as far as possible, therefore, if do not activate any label in this certain power level, just stepping apace of reader 100 (usually with incremental mode) is to next power level.If sense signal in this certain power level, reader 100 just can begin whole demodulation process 1390 (may adopt the conflict mitigation technique of discussing among the lower part V) so.Notice that in other embodiment of this system, reader 100 can also send modulated carrier signal, lock-out pulse, or asymmetric carrier waveform, and do not lose generality.

The signal processing that reader 100 is carried out can make up with certain of hardware or software configuration or they and carry out.Exemplary embodiments comprises certain selectivity 1365, amplifies 1370, analog-to-digital conversion 1375, and DC obtains and gain control function.Usually, each in given communication journey of reader 100 circulation may communication channel (or sequentially or simultaneously), seeks the signal energy on each.One skilled in the art would recognize that many modes can be used for the existence of detection signal, detect the existence of conflict or do not exist that this can change based on modulation or signaling type.In certain embodiments, reader 100 can also be carried out carrier signal active or the passive inhibition to it usually, and interference or noise removing (for any type of interference from the source the label of expecting in system).

As mentioned above, the preferred embodiments of the present invention are utilized band spectrum modulation in label 110,120,130.Therefore, as known in the art, must be in reader 100 by at first using the signal that receives on each possible each yard of spreading code despreading channel.

More specifically because the preferred embodiments of the present invention utilize specific lengthening m sequence as label 110 sequence spreading, therefore in reader demodulation process 1390, can utilize very quick, effective and novel demodulation (that is, despreading and channelizing) technology.These technology can reduce the required processing power of (for example, in the preferred embodiment by an about factor 57) reader demodulation process 1390 greatly, and this can make the reader time for reading faster and cost that realize is lower.Actual processing saving amount depends on the channel quantity that is adopted in each journey of multipass system, can express with a factor (F), wherein this factor equals the ratio (the use receiving sequence reorders and a kind of new combination of fast Hadamard transform (FHTs)) of quantity with the improved de-spreading operation quantity of traditional de-spreading operation that each symbol needs:

$F=\frac{1}{L}\underset{i=1}{\overset{L}{\mathrm{\Σ}}}\frac{{\left(N_i\right)}^2}{N_i*\log N_i}=\frac{1}{L}\·\underset{\mathrm{lpasses}}{\mathrm{\Σ}}\frac{N_i}{\log N_i},$

In the formula, L is successfully the quantity of the needed journey of demodulation source data, N _I(once more) equal the quantity of channel in i the journey.Processing saving amount in this factor direct representation reader demodulation process 1390 (it is typically represented according to millions of operations of per second (MOPS) or the millions of instructions of per second (MIPS)).Therefore, in this embodiment, in optimal cases (no conflict as described below alleviates), reader 100 can utilize the processor 1390 of performance low 57 times (for example, 10MOPS vs.OPS) in the preferred embodiment.

Notice that specific lengthening m sequence (shown in the frame 1120 of Figure 11) is that the quadrature of the PN sequence of routine expands, it is similar to quadrature Walsh sign indicating number (shown in the frame 1420 of Figure 14) a bit; That is, these two groups of sequences all have the binary one and 0 of equal number in sequence.In fact, this sequence of two types (that is, specific lengthening m sequence and Walsh sequence) can be interrelated by single certain heavy ranking functions of use.This certain heavy ranking functions directly obtains from primitive polynomial, and this primitive polynomial is used for producing basic m sequence (as shown in the sequence label generator 1110) at the receiver block 1520 of reading of Figure 15.The sequence function 1510 that reorders is used for when receiving system 1375 receives sampling of datas (or element) data sampling rearrangement.Receiving system 1375 can be a digital to analog converter, simulated sampling and holding device, and register or other are any can to receive the good device of letter.Note, this synthetic received signal is used a single sequence 1510 functions that reorder, this synthesized received signal is by using a plurality of yards channels (or as in 110 code phase) to form from the signal that several different labels 110,120,130 transmit.

In case receiving sequence reorders in the storage medium such such as storage buffer 1530, a sequence in its similar one group of effective Walsh sequence, and can utilize such as the such Fast transforms technology of a kind of quick Hadamard (FHT) to come fast (and simultaneously) the data (as 1540 as shown in) of all data channel despreadings from label 110.FHTs is used to correlated sequences of data and complete Walsh code character (walking abreast) apace, and this is being known in the art.Any conversion of relevant FHTs (for example, Fast W alsh conversion, Walsh-Hadamard conversion, recurrence Walsh conversion or the like) can be used together with above-mentioned fast correlation method and not break away from spirit of the present invention.Be also noted that in addition all described treatment technologies can be carried out in analog or digital signal processing territory.

Notice that traditional FHT algorithm (for example, shown in frame 1410) has been proved to be well, and figure 14 illustrates their taproot operation (frame 1400 is called " butterfly computation ").Radix be 2 FHT butterfly computation to be similar to radix be 8 FFT butterfly computation, but it multiply by a+1 by data element and-1 value is formed (or being equivalent to add together and subtract this numerical value).Also show the lattice structure 1410 of a 8 * 8FHT.Each output of FHT 1550 is called a FHT binary sequence (bin) or FHT sign indicating number channel.Because FHT is a Fast transforms, therefore as can be seen, for a N point orthogonal sequence, the processing saving amount on tradition relevant (factor F that expresses above being similar to) equals (N ²/ NlogN).Same saving amount can realize by utilizing described fast correlation technology.

Determine to receive accurately data rearrangement order function 1520 by the state that during normal running, (also refers to following Example) and observe label fibonacci series (Fibonacci) LFSR (shown in 1110) circulation.The state of LFSR progress is directly corresponding to an indirect address, and this address is their necessary address stored in time receiving the storage buffer that receiving data when (linearity) comes in the reception sampling of data of (expansion) (1530 or other storage mediums).The sequence of this address (1520) can be stored in (for example, random access storage device, read-only memory, hard disk drive or the like) in the storage medium alternatively, rather than initiatively produces in receiver.By this way, the element of the m sequence of reception (or m sequence and) is rearranged preface, and they just in time represent element in the Walsh sequence (or more specifically, the row in the Hadamard matrix) now like this.Like this, traditional quick (Hadamard) conversion (being correlated with) method can be used for the data channel that (1540) parallel despreading receives now.Note, data sequence can also be in memory double buffering, to adapt to any processing delay.

The output index (indexes) (or binary sequence (bins)) 1550 of the FHT of expression signal energy is directly simplified the mask value 1130 (when with binary representation) that circuit 1100 uses corresponding to the AND-XOR in label 110,120,130.For example, channel option code 1130 (shown in Figure 11 ' c0-c4 ') (transmitter processes) directly corresponding to Figure 15 in effective output 1550 of FHT piece 1540 of (receiver processing).Notice that application binary mask value 1130 is selected a specific sign indicating number channel (or code phase) in label 110.This also figure 7 illustrates, and extracts mask 710 from label data 240 here and selects 240 to output to channel.Just, binary mask value 1130 (and FHT binary sequence index) is directly corresponding to the data 221,222,223,224 that are stored on the label 110, they are used to during specific journey to select a channel (referring to the identifier in Figure 17 and 18 1710,1820,1830 and 1840, how their label datas that is used to remark additionally are selected relevant with channel).In a preferred embodiment, during each journey of multipass algorithm, each label 110 sends its data 220 on a fixed channel 1260.The delivery channel level of each FHT binary sequence is directly corresponding to the channel level on each yard channel 1260 after the expansion.As further discussing below, the data-signal 1550 of each effective FHT binary sequence output can be tested (because for valid data, two sequences should be mated) by it and binary system FHT index value are complementary during the channel selection portion of receiving data sequence is divided.Pass#2 to the multipass transmission algorithm in Figure 18 has represented this technology.Note, be equivalent to the binary representation of FHT binary sequence number about the data sequence 1820,1830,1840 that is used to the part 222 of the second journey selective channel 240.

In a preferred embodiment, by reordering and the FHT technology of combination shown in Figure 15, demodulator can all possible channel of fast demodulation (that is despreading) (that is code phase).Note, in each the receiving symbol cycle in receiver (data channel that it is possible corresponding to each and signal required go channelizing and de-spreading operation), typically need a N point FHT to come demodulation N channel.Be also noted that other embodiment of transponder system can utilize quadrature Walsh sign indicating number as the channelizing function, the FHT binary sequence is directly corresponding to Walsh sign indicating number channel indexes (and not needing the processing of reordering) in this case.But compare with preferred embodiment, such system does not have good antijamming capability, because the Walsh channel code is periodic and may be relevant with the PERIODIC INTERFERENCE source height.Therefore, the preferred embodiment of this system utilizes specific lengthening m sequence as the channelizing function, and utilizes above-mentioned demodulation techniques.

As an example, be 16 (N=16, the system of specific lengthening PN sequence n=4), the channel selective value 1130 (n of ' 0001 ' (1) with binary system in tag transmitter, utilizing length _i) represented sequence 1260 is ' 0111101011001000 ', and the represented sequence 1260 of the channel of ' 1001 ' (9) selection (mask) 1130 values is ' 0010110010001111 ' (this is different time skew or code phases of same basic m sequence just, have specifically increased by one thereafter and have guided zero) with binary system.The label PN that has represented to be used for the primitive polynomial of 23 (representing with the standard octal notation) in Figure 11 produces and the example of mask circuit.Suppose independent these sequences of on communication channel, launching of two tag transmitter.The reader receiver will use specific reorder function 1520 and a FHT to handle (as shown in figure 15) and analyze this two signals.The PN sequence that sends the specific reception sampling of data that must use to reorder for this example be { 0,15,7,11,5,10,13,6,3,9,4,2,1,8,12,14, with identical shown in 1120 }.Can be by duplicating a m sequence generator 1110 and observe PN generator state, or, in reader 1110, produce this sequence by the required sequence that reorders of storage in memory simply, wherein in label 110, utilize this generator.The sequence that reorders is used to use addressing indirectly that the reception sampling of data stream of coming in is stored in the memory.For example, the first effective A/D sampling that arrives reader is stored in the storage buffer position 0 (all is like this to all specific long codes that add) of storage medium 1530, and second sampling is stored in memory location 15, the three sampling and is stored in position 7, or the like.In case receive N (being 16 in this embodiment), just the FHT to the new sampling of data operative norm that reorders in the storage buffer 1530 handles 1540.Reordering function will be ' 0001 ' PN sign indicating number ' 0101010101010101 ' (it is identical with Walsh sign indicating number 1) that is converted to sequence, and ' a 1001 ' PN sign indicating number ' 0101010110101010 ' (it is identical with Walsh sign indicating number 9) that is converted to sequence.FHT 1540 will point out that signal energy is in the binary sequence 1 (corresponding to channel code 1) and binary sequence 9 (corresponding to channel code 9) of (for example, label sends) output 1550.Like this, the binary sequence 1 by observing FHT output and each emission symbol of binary sequence 9, remainder that can the sensing label data.

Note, by supposition first chip (or symbol) that label 110 sends in receiver is binary zero (it is equivalent to the a+1 normalized signal value on the channel), although in fact not having such data sends, technology recited above can be used to traditional (that is nonspecific lengthening) m sequence.Like this, the first buffer positions value of being initialized as a+1 in storage medium 1530, and (that is, reorder 1510 and FHTs 1540) handled in continuation as usual.By this way, can carry out very fast for a plurality of yards channels (or code phase) of conventional P N sequence relevant.Can also be to insert this sequence wherein by following the tracks of additional chip (that is, except described first chip), thereby can adapt to other standard lengthenings PN sequence.

Above-mentioned fast correlation technology (promptly, special receiving sequence reorder 1510 and FHT1540) can use any communication system, the PN sequence that these systems use an AND-XOR to simplify network 1100 to be produced (no matter they whether with such network generation).Many general communication systems are utilized the PN sequence of these types or from the sequence that combination produced of traditional m sequence (all sign indicating numbers of Gold as everyone knows).The example of some such systems is IS-95, IS-2000,3GPP CDMA Cellular System, and GPS CDMA navigation system.Top fast correlation technology also can be equally effective in these systems.

In any situation (irrelevant), as illustrated, in receiver front end 1610 necessary filtering and the synthetic received signal of amplification, channelizing in reader 100 then (or going channelizing) 1620 at Figure 16 with the channelizing technology that adopts.For signal and collision detection purpose (usually in 1630), (but possibility simultaneously) handles each channel usually respectively then.For example, using the Walsh sign indicating number to replace still can utilizing a FHT operation to come all different pieces of information channels of demodulation simultaneously as mentioned above among another embodiment of system of described m sequence.Other embodiment of this system can utilize the traditional despreader memory bank of (replacing 1540,1620) (parallel or time-division) to carry out channelizing and despreading is handled.A despreader typically is made of a multiplier with integration and dump function, and this is being known in the art.

In another embodiment of communication system, other embodiment can utilize the quadrature time slot as channel (for example in a time-division ALOHA system), in this case, the signal from different labels should carry out demodulation (on the difference in time) when they arrive.It is noted that the conflict that selected channelizing method can not change in reader 100 the general type that adopts alleviates algorithm, this algorithm is further described below.

Be also noted that normally repeatedly iterative processing of demodulation process in many embodiment of the present invention is because typically label that can not be all can both succeed in sending up their information on first journey of multipass transmission algorithm.Therefore, reader 100 must keep powering up (in same power level) and demodulation data of coming in continuously, all successfully is received (further using method described below) up to all data from label.Also have, when utilizing senior conflict mitigation technique 1630 (describing in detail below) at reader 100, each Cheng Keneng of multipass algorithm needs repeatedly demodulation iteration (that is, FHTs).Be also noted that described in discussing as superincumbent dynamic channel configuration file, the journey subsequently of multipass transmission algorithm asks demodulator to hold many new channels possibly.

V. conflict alleviates method

As mentioned above, in this (or any) communication system, it is limited that label 110,120,130 can be used to be sent to the number of communication channels of reader 100.Because number of communication channels is limited, and between a plurality of labels amorphous channel allocation (that is, effectively utilizing Random assignment), therefore the transmission collision from label is just inevitable in described system.Conflict definitions is situation or an incident of two or more labels whiles (that is a concrete journey that sends at multipass) selecting same channel to send.Should be noted that distribute to be effectively at random, because illustrated, be stored in data on the label very near the uniform random number certificate as the part I of this paper.

In described system,, also may utilize or not utilize conflict mitigation technique (being described in further detail below) in the reader 100 according to the expectation complexity of reader 100.For example, a low-cost receiver may not utilize any conflict mitigation technique, and a higher cost (higher processing power mode) receiver may utilize senior conflict mitigation technique.

General discussion is below at first supposed and is not utilized special conflict mitigation technique, and investigates the situation of utilizing the conflict mitigation technique subsequently.Whether note utilize conflict to alleviate no matter use in reader 100, label 110,120,130 all sends identical pattern.Each label (that is, 110) in fact " be cannot see " other labels (for example, 120,130) in the system.In receiver, carry out ensuing additional step, just further carry out demodulation process.

Especially, in a preferred embodiment, typically detect the existence that departs from the less ASK signal of label with the absolute value that obtains normalized signal and check residue (standardization) signal by deduct any average signal level (that is the dc value in 1380) from a channel.Note, can also use automatic gain control (also in 1380) and come further normalized signal level.In a preferred embodiment, if the absolute value of normalized signal level surpasses certain threshold value (usually on certain time cycle), illustrate to have a signal on that channel.

In case detect a signal on a particular channel, reader 100 just typically detects conflict whether occurred on that channel.This typically can be by checking that the variance (variance) of the absolute value of standardization signal level realizes on certain time cycle.If the variance of the absolute value of signal surpasses certain (difference) threshold value, illustrate conflict (owing to the conflict binary data value of the ID data of different labels-) on that particular channel, to have occurred referring to Figure 17; Otherwise, illustrate on that channel, to have an independent signal (in Figure 18).One skilled in the art would recognize that and to measure and designator filtration and average these, so that increase their reliability (for example, in order to increase the SNR of estimation).Therefore, the times of observing these measurements (and utilizing) in last filtering are long more, and it is accurate more and reliable more that estimation will become.Also can pass through another device, detect conflict such as standard error detection (for example CRC) device.Be also noted that no matter whether conflict on a channel, occurs, can adopt the standard error correction device to proofread and correct the accuracy of error of transmission and the estimation of raising signal.Typically all in a given journey available (possibility) communication channels (as mentioned above, it can change along with the number of passes of multipass algorithm) go up and carry out these detections.

Like this, reader 100 identifies typically whether all (each) in each journey may exist any signal on the communication channel, and whether has appearance conflict on each channel of signal.Explanation once more, conflict is generally defined as, during the same journey of multipass algorithm, the same communication channel of two or more label utilizations.When conflict occurring on a given channel, if do not utilize any conflict mitigation technique, the data of that channel will be lost usually so.If on a given channel, have a signal, and do not detect conflict, the particular data that has successfully received on that (given) channel just typically is described, and reader 100 can be known the whole data sequence of that specific label usually.

Notice that some embodiment can also carry out error detection or error correction (or integrality standard of some other types), effectively and correctly receive so that guarantee data.Be also noted that, select data if launched tag channel, reader 100 can also tags detected 110 communications on the communication channel of expection really (play the error detection mechanism of another kind of form-referring to Figure 18 to being used for determining the data division of channel as mentioned above, here select data 222 must cooperate channels to select for the channel of second journey, these select data with 1820,1830,1840 marks).

In case know (and may confirm) signal from label 110, just can from the overall remainder of signal, ignore or remove (as described below) it.If from signal is overall, effectively remove (by various possible algorithms) signal, just can realize that a kind of conflict of form alleviates from a specific label.Notice that the benefit that alleviates in order to obtain to conflict needn't accurately be removed this signal.

Figure 19 represents when utilizing the conflict mitigation technique, the general flow figure of reader action.In this case, before proceeding next journey of multipass transmission algorithm (for example, in a preferred embodiment by making the reader transmitting power constant), reader 100 is analyzed conflict as much as possible (for example, the error in the data) as far as possible.

As mentioned above, reader 100 keeps usually with a given power level, discerns all effectively certain level of confidence (or probability) of emission label up to reaching.

If from signal overall (or synthesized received signal), do not remove (or deducting) this signal, illustrate not conflict so to alleviate.In the sort of situation, may in reader 100, use various algorithms, successfully to obtain (or demodulation) all data from label.In this case, general idea is at least one journey of multipass source apparatus transmission algorithm, waits for the communication channel of each label selection one unique (just, unique user takies).This technology normally can be used for the recognition methods of the minimal complexity of reader 100, but it also is the slowest (that is, needing the longest overall transmission time to transmit a block message) usually.

Do not utilize the situation of conflict mitigation technique for reader 100, one very the algorithm of low complex degree be to make label 110,120,130 send the number of passes of multipass communication of algorithms maximum quantities simply.Can determine the maximum quantity (as mentioned above) of journey during the unique part of the data of typically on using up label, storing.

As mentioned above, by controlling the first and second predetermined transmission conditions, the quantity of the journey that reader 100 direct control labels are launched.In a preferred embodiment of the invention, in order to continue fully transmission between the activated label, it is constant that the reader transmitted power level keeps, but also may be that other the first and second predetermined transmission conditions are controlled the transmission group from label.The maximum amount of data of journey determines by specific channel selection algorithm usually, but be restricted to usually data length (bitwise) divided by be used for data channel that unique fully (not overlapping) channel selects select part and.Like this, there is the channel id of the data of 128 bits and 8 bits to select in the example of data in the above in each journey that provides, communication journey maximum (promptly 128/8) (before beginning the interactive channel selection once more) that be 16 in the multipass algorithm.Like this, (for example, PN) character rate can be determined maximum query time to a given in a preferred embodiment channel, and always obtains (or reading) time (described in equation in the above) for all situations is fixing.

Other (in many more complicated situations) do not use the algorithm of conflict mitigation technique also is possible.Such selection is the number of passes (less than maximum) that makes label 110,120,130 emission limited quantities, obtains a correct given level of confidence that receives data (or carrying out the label stock) like this.This determines by the anticipated number of the source apparatus (or label) of (or on each powers on level) existence in the system and the level of confidence (or probability of clauses and subclauses in the successful recognition system or label) of expectation usually.For example, according to dynamic channel configuration file given in the previous example, emulation (about 1000 tests) demonstrates, and on average need 7.73 transmission journeys to discern 50 labels, but the needed maximum number of passes of unique identification label is 10 in 1000 tests.Like this, reader 100 can keep powering up at a given power level to 10 journeys, so as for all 50 (or such) labels successfully on a unique channel their data of emission have a rational confidence level.Reader 100 need only determine when on the channel that receives label ID data to have only a label 100.This will save total acquisition time greatly, because only carry out 10 journeys rather than 16 journeys of bare maximum of providing of example in the above.Further emulation, for given amount labels, should applied statistics or probability analysis determine other the level of confidence or the quantity of journey.Notice that in some applications, when carrying out the stock for the first time, reader 100 can utilize the journey of maximum quantity, adjust the quantity of journey based on (that is, measure or observe) number of labels of expecting in the system then.

Alternatively, the algorithm that reader 100 uses can be followed the tracks of the expection collision position (that is, channel) of each label (in case its data or id information successfully are received), and estimates also remaining how many labels will be discerned in system.Like this, reader 100 can be than stopping query processing sooner in above-mentioned technology (in case it determines may not exist other label in system).In other words, required transmission number of passes amount is estimated in the reception period self adaptation by reader 100, rather than is carried out precomputation according to above-mentioned expection number of labels.Further describe this technology among example below and Figure 22.

Reader 100 more senior embodiment can utilize any in the conflict mitigation technique of several forms.The conflict mitigation technique can reduce the conflict influence on given communication breath channel usually.Ideally, they can eliminate the influence of the particular conflict on the channel.This can realize in said system by producing a known signal again and deduct this known signal from resultant signal overall (or synthetic received signal).Notice that this interference signal subtraction can carry out (for example, it can carry out or carry out with spreading rate in a preferred embodiment) any stage in demodulation process after despreading.The preferred embodiments of the present invention are carried out conflict in demodulation (that is, despreading) back and are alleviated, so that reduce the complexity of equipment.

Usually, when utilizing the conflict mitigation technique, known signal is many more, for a given journey of multipass algorithm, seems that the label that exists is just few more in system.Because in a preferred embodiment, the data that are stored on the label 100 are directly determined channel selection (or reader 100 is known), in case reader 100 successfully receives data (usually when label 100 is launched) on a different unappropriated channel, for each journey of the multipass communication of algorithms, it just knows all channels selections that label 100 is carried out.Like this, as above, reader 100 can predict which channel label 100 may utilize be used for further () emission and in the past.Notice that during normal signal detects processing, also measure the signal level of being observed from label 110 usually in reader 100, therefore given (not conflicting) reliable estimation of label actual signal intensity is effective.This knowledge can be used for rebuilding effectively known signal and accurately deduct it from the signal of overall reception, thereby eliminates its influence from other transmission journey.

As a rule, gang's conflict mitigation technique can change complexity, and they are usually than the realization more complicated (for example, requiring more processing power, memory and hardware) that does not utilize the conflict mitigation technique.But such technology can obtain short how total label data usually and obtain (reading) number of times, and can improve the capacity of system greatly.Suppose that channel is accurate static, so for optimal system performance, this system is the comparison linearity.

The fairly simple conflict of a kind of form alleviates and comprises deduct known signal (on the forward direction with respect to the time) from the journey subsequently of multipass algorithm.Like this, the conflict of this form alleviates and is commonly referred to the forward direction conflict and alleviates.Figure 20 represents to use the example flow diagram of the reader of forward direction conflict mitigation technique, here to carry out this processing in the mode of order (for example next channel), conveniently to understand this processing.This processing generally includes determines which label 110,120,130 has succeeded in sending up their ID data (described in superincumbent receiver algorithm), and preserve a data structure (or tabulation), this data structure comprises the selection of known (label) channel and the estimated signal level of each journey of multipass algorithm.In case the signal level of the ID data of a label and the label signal of being launched is known, can from any conflict subsequently that relates to this label, eliminate it effectively.Note once more, can on the time span that increases, measure and filter this signal level, with the interference signal level accuracy level that is improved.Like this, in one embodiment of the invention, in case estimated a label signal (in certain accuracy level, determining), just can in the journey of the back of multipass transmission algorithm, from the channel of suitable (with determining), deduct it, on other signals of other users' emissions, eliminate any interference effect of that (known) label signal.Because the certainty matter that each tag channel is selected just can adopt this technology, wherein channel is selected typically based on the data that are stored on the label 110.

The supposition of accurate static channel is very important here, because for all journeys subsequently, supposes to keep measuring-signal (measured signal) level.Usually, for slow variation channel condition is described, signal level is estimated and can each be transmitted Cheng Gengxin once.Note, carry out this algorithm only need store known label signal information (typically be included in Data Receiving or tabulation in) and from the synthesized received signal (or burst) of current transmission journey (described as following algorithm, this with all are received happen suddenly be stored in the memory relative).Usually, such forward direction conflict alleviate algorithm can be than not carrying out improvement that method that any conflict alleviates obtains bigger (2-4X) total time for reading.

Another kind of more senior conflict alleviates and relates to from the journey subsequently of multipass transmission and deduct known signal the journey before.This may be because, in case identification from the data of a label 110, its shared channel just can be determined and it also just can be eliminated the effect of the conflict of any journey before in journey before.This class conflict alleviates algorithm and is commonly referred to two-way conflict mitigation technique.Two-way conflict alleviates calculating more complicated (and requiring more memory to store communication journey before usually), but can reduce total time for reading (reducing a magnitude on the method for not carrying out any mitigation conflict) greatly.

Usually, this method requires data structure of storage, and this data structure comprises in each communication journey of the label of being discerned known channel and selects and estimated signals level (in superincumbent situation).But, owing to from transmit journey (except as working as the future the forward direction collision algorithm) before, deducted signal, thus other conflict can be analyzed.For example, if the data from the 3rd journey of the multipass communication of algorithms are analyzed (promptly, success receives), just can make from other user's data and can in the previous journey (i.e. second journey) of this algorithm, analyze, the user who in previous (for example, first) of transmission or back one (for example the 3rd) journey, is conflicted before just can discharging so successively.Analyze from a new user's data at every turn, from all transmission journeys (up to and comprise work as future) deduct its reconstruction signal, and estimate the quantity (for all possible communication channels) of conflicting once more.By this way, the available transmission journey that reader 100 can circulate all (up to and comprise work as future), and analyze more label signal in fact continuously, up to any one journey (up to and comprise work as future) in all do not have more user to analyze.Reader 100 can step to next power level then and continue this two-way collision algorithm.This effect may be more powerful in the transmission journey of back, thereby can analyze the label signal more much bigger than the quantity available of communication channel.

In case received all label datas, reader 100 just can be by the integrality of above-mentioned mode (for example EDC error detection and correction) check data.Reader 100 can also carry out reprocessing to these data, typically comprises such as descrambling, deciphering, classifies and remove the such function of redundancy (it can power up in the energising scope more than in a preferred embodiment of the invention).Notice that the some or all of of these functions can be carried out at a concentrated position, thereby serve a plurality of readers and antenna.

The example of system operation

The operation of these algorithms may best illustrated by example.These examples will describe the simplification idealized system of a label in detail, the accidental channel in each journey of wherein having drawn.The Figure 21,23 and 24 that is used to explain this example is state block diagrams of system, represents the channel that each label communicates on each order journey of whole algorithm.State in this example is the unaltered output of an actual tests, and wherein this test uses a random number generator to come selective channel.Irrelevant with the type of physical channel (for example, code phase, time slot or the like) in this.Because the data scrambling part of the present invention described in the part I in the above, this will provide model more accurately for whole system.

The example supposition of describing in detail at Figure 21,23 and 24 one has eight labels, and supposes that further each journey of eight channels has a fixing channel quantity, and label communicates from these channels.Like this, in a preferred embodiment, 3 bits of each label (unique a group) id information is used to select in eight channels, and this is that each label 110 is used for the channel that sends during each journey.Represent with octal digit, the one or three ten bit of label ID be produce at random and following repetition for convenience:

Label 1:0033 0436 07...

Label 2:1106 2551 65...

Label 3:4767 4416 41...

Label 4:2044 6111 36...

Label 5:6072 3355 74...

Label 6:1476 5432 40...

Label 7:5443 3675 34...

Label 8:2135 5115 64...

Label 1 is selective channel 0 during journey #1, and selective channel 0 during journey #2, and selective channel 3 during journey #3, or the like.Label 2 is selective channel 1 during journey #1, and selective channel 1 during journey #2, and selective channel 0 during journey #3, or the like.As can be seen, for journey #1, it eight advances the index word to select a channel, label 1 independent busy channel 0, label 3 independent busy channels 4, label 5 independent dedicated channels 6, label 7 independent busy channels 5 from first from this tabulation.Because not conflict in these channels, label 1,3,5 and 7 just can be identified fully; Label 1,3,5 and 7 transmits their complete ID respectively on a channel of not conflict.But on journey #1, label 2 and 6 has conflict on channel 1, and label 4 and 8 has conflict on channel 2.These labels can not successfully be identified, and therefore need to analyze journey subsequently.Reader 100 is observed and is had conflict, just is retained in the used power of current level and allows all labels to select to be used for another channel of journey #2 according to second octal digit.Should be noted that without any label and know whether they have successfully transmitted their ID.

In journey #2, the label that does not relate to conflict has only label 3.Because this label is identified in journey #1, reader 100 does not obtain any new information.The label neither one that is in conflict in journey #1 may be identified.Statistics, for eight labels and eight channels, the probability that has once conflict at least be 1-8! / 8 ⁸=99.76%.This is not have between M label on a given N channel the more ordinary circumstance of probability of conflict

And P{ conflict }=draw in the fact of 1-P (not having conflict).For each journey of whole algorithm, have at least the probability of once conflict identical therewith.This combination for label and channel, 100, be averaged in 000 test, unappropriated channel is 2.7498 in eight channels of each journey, and 3.1386 channels comprise an independent label, and 1.5737 channels comprise two labels, 0.4482 individual channel comprises three labels, 0.0796 individual channel comprises four labels, 0.0093 channel comprises five labels, 7.2 * 10 ^-4Individual channel comprises six labels, 4 * 10 ^-5Individual channel comprises seven labels, and does not write down the situation of eight labels in a channel.

There is not the example that conflict alleviates

Because conflict does not alleviate, in order to be identified, label must lean on them oneself to reveal in a channel.If allow this test to carry out enough repeatedly, this will take place.But, in label ID220 information, have only the bit of limited quantity, this test can only move limited number of times before it begins repetition.For example, if label ID is 96 bits, and each journey selects a channel (in eight) with 3 bits, and therefore after 32 tests, this processing will begin repetition.Owing to have the once probability very high (is 99.76% for this situation) of conflict in each journey at least, have possible " hiding " probability in collision of a label ID very little and limited on each of whole test and each journey.This is not to mean the ID220 of a label identical with the ID of different labels (this does not meet unique tags ID and unique supposition that reversibly is mapped to a scrambling label ID).Its all implications are that when when the seldom bit (this situation is three) of the channel space that is used for definite that journey is gone up inspection, the ID of other labels of ID220 and at least one of label is identical.This has just entered stock or the probabilistic notion of clauses and subclauses, and a label stock is known to certain confidence level only here.

For the test of the example among 21 figure, eight tests of each labeling requirement just can appear on the channel that does not have to conflict.Mention, label 1,3,7 and 7 is discerned in journey #1, and label 2 is discerned in journey #3, and label 4 and 8 is discerned in journey #4, and label 6 just reveals up to journey #8.Label 6 is how a label is hidden a unique good example in collision, though it has a unique ID.If should test only move by journey #7 (that is, if ID has only 21 bit long), label 6 can not be identified.

In journey #1, four labels have been discerned.Also discerned two conflicts, this explanation has at least four other labels (because at least two labels just can cause a single conflict, at least four labels just can the amount of a causing conflict).After first journey, reader 100 can define four known label and at least four Unknown Labels, or has eight labels altogether at least.

In journey #2, have only an independent known label before to take the channel of unique (using).Because reader 100 is known the complete ID of label 1,3,5 and 7, thus it know next time with all subsequently in the journey these labels will take which channel.Reader 100 knows that label 1 and 5 will arrive on the channel 0, and label 7 writes to 4.Reader 100 just can reckon with on the channel 0 that conflict is arranged like this, but might also have the label an of the unknown also to take channel 0 (in this case, being label 4).Channel 0 indication has two known labels and one or more Unknown Label.Reader 100 does not reckon with the conflict (because select that channel without any known label expection) on the channel 1.Two other Unknown Labels of a conflict explanation are arranged here, also may be more.Conflict on channel 4, owing to only reckon with label 7, therefore explanation has few other the unknown.Like this, the known label before journey #2 obtains four, and at least three (clear and definite) Unknown Labels.This is less than the set of determining in first journey, because be four Unknown Labels and at least four Unknown Labels in first journey, so reader 100 is not collected any new information in second journey.

In journey #3, label 2 is identified on channel 0.Label 1 is can write to 3 a unique tags of expection, and therefore the there has a conflict explanation to have a Unknown Label at least.Label 7 is can write to uniquities of 4 of expection, and therefore the there has a conflict explanation to have two Unknown Labels (Unknown Label on Unknown Label on the channel 3 and channel 4) at least.Label 3 is independent once more.Label 5 is can write to unique tags of 7 of expection.The there has a conflict explanation to have three Unknown Labels (continuing the Unknown Label on channel 3,4 and 7) at least.These and present five known labels, explanation has eight labels at least again.

The label 4 and 8 that journey #4 identification is new.Label 3,5 and 7 occurs on the channel that does not have conflict.Label 1 and 2 is expected at conflict on the channel 6, but may also have other label.This just has seven known label, and from the test of front as can be known, also has a Unknown Label at least.

Journey #5 does not discern new label.Conflict on channel 5 is not expected, seven known label and at least one Unknown Label are described once more.Journey #6 and journey #7 are similar explanations.

In journey #8, identification label 6.Every other conflict all is expected.Eight labels of having discerned are arranged now, just the minimum number of from journey before, expecting.But, still have label and hide in collision.For example, have a label selective channel 1,0,4,6,3,1,1,5, and this label is hidden by other conflicts.Probability with label of this special ID is 1/8 ⁸Or 6 * 10 ^-8

Also have a label selective channel 2,4,4,6,5,4,5,6, probability also is 6 * 10 ^-8Generally speaking, two conflicts are arranged in journey #1, three conflicts are arranged in journey #2, three conflicts are arranged, a conflict is arranged at journey #4 at journey #3, journey #5 has two conflicts, journey #6 has two conflicts, and journey #7 has three, and journey #8 has three conflicts, 2 * 3 * 3 * 1 * 2 * 2 * 3 * 3=648 possible hiding ID arranged, each probability 6 * 10 ^-8, be 648/8 for the probability that an independent hiding label is arranged in addition ⁸=38.6 * 10 ^-6(38.6ppm).There is the probability of two hiding labels littler in addition, 648.647/8 ¹⁶=1.5 * 10 ^-9By data being gone to disturb and for example when every other article are the groceries article, determine that a hiding label may be relevant with a tire (tire) or certain other unexpected article, in other embodiment, may further improve stock's level of confidence like this.

Can continue operation by the expection label (in this, in the situation, being 8 labels) that allows test discern minimum number afterwards, thereby reduction there is the probability of a hiding label based on conflicting information at it.By calculating the number of collisions of each journey, and can know the probability of hiding label based on the channel quantity of each journey, reader 100 can continue to move journey, satisfies certain level of confidence or moves out of unique channel form (exhaustive ID) up to it.Suppose each journey 648 ^1/8=2.246 conflicts in two additional journeys (ten altogether) afterwards, have a probability of hiding label separately to be reduced to 3.04 * 10 ^-6Two more additional journeys (12 altogether) afterwards, there is a probability of hiding label separately to be reduced to 240 * 10 ^-9The geometric progression that each additional journey has the probability of a hiding label approximately to reduce is 648 ^1/8/ 8=.281X.

Figure 22 illustrates a flow chart, the step that is comprised in the method that does not have interference eliminated in the expression.In beginning 2210, system initialization is not have the ID that determines and do not have unknown ID, and they are together corresponding to sum zero item.After the analysis 2230 of first journey 2220, the ID (for example, the clauses and subclauses among the journey #1 1,3,5 and 7) that determines is recorded and adds in 2240 to definite ID tabulations.Number of collisions in journey 2250 also is recorded (for example, being two conflicts) in journey #1.If conflict is 2260 of expection, whether a possible unknown ID is so just arranged but determine unknownly, this unknown ID may show in the journey of back.If conflict is not 2270 of expection, the ID that so just adds two the unknowns is in the unknown tabulation.Estimate that then 2280 determine the clauses and subclauses of identification and the sum of the minimum number of the unknown ID that causes the conflict of being write down.Suppose and determine that ID is not equal to the total item of estimation that unknown sum just is reset to 0 2295 and initial another journey 2220.When the maximum quantity of the ID of identification adds unknown ID quantity and satisfies a predetermined level of confidence 2296 before the ID quantity of determining equals, withdraw from circulation 2290 at last.

Up to the present, there is not the time dependent any supposition of relevant channel and received signal level.No matter channel be static state or the time dynamic, can use " do not have conflict and alleviates method ".For the situation of static channel conditions, the signal that returns in this case has known power level and phase place, and more information is used in reader 100 with the form of received signal level.If supposition now, which channel a known label can be selected outside in knowing the journey of back, and also known its signal level so just can determine to expect whether other hiding label is arranged in conflicting.For example, the conflict on channel 0 during the journey #2 comprises two labels and a Unknown Label.If the signal level of known label is also known, Chong Tu resultant signal level just can be compared with each channel level so, so that determine a hiding in collision other Unknown Label.A condition like this will allow reader 100 to be identified (in this case, being 8 journeys) independently at all labels and determine to stop its inquiry, because all conflicts can be explained without any after hiding label.

The knowledge of the signal level of identification label provides higher confidence level in stock control.But, after occurring separately, just stopping outside the inquiry when all known label, signal level information also provides the improvement aspect acquisition time.This is in ensuing part discussion.

The forward direction conflict alleviates example

When label of independent identification, subsequently the journey, it all is known that its channel is chosen in reader 100 concerning all.If the channel level of label and phase place also are known in addition, that label just can have been eliminated for the influence of conflict so.Signal from this label can be removed from conflict subsequently basically, thereby removes it effectively from sum (population).Consideration is in the test shown in Figure 23. Label 1,3,5 and 7 is identified definitely during journey #1.Signal level and the phase place of supposing them also have been determined.

During journey #2, known label 1 and 5 is launched their data on channel 0.By their known signal level, they can be deducted, and only stay label 4, and label 4 just can be identified now.Similarly, label 7 is expected at its data of emission on the channel 4 during the journey #2, and eliminates this label, and just only remaining label 6 can be discerned separately.Conflict on channel 1 is not still analyzed, so whole algorithm at least also needs a journey in addition.

During journey #3, label occurs separately and is identified.Label 1 is expected on the channel 3 data that send it, so it can be deducted, only remaining label 8, and label 8 just can have been discerned now.Every other conflict only comprises known label, so has just finished the accounting of label in three journeys of whole algorithm, rather than 8 of not conflict shown in Figure 21 or multipass (depending on required level of confidence) more, and has full confidence level.

For a static channel, the channel strength of the label of identification can be known as pinpoint accuracy.Consider the situation of lengthening PN channel.For this test, label can be selected the different code phases of the lengthening PN sequence of one eight chip lengths.According to the sensing of specific ID bit, the long PN sequence of this eight chip should be actual transmissions or each bit of label ID overturn.At reader 100, the correlator in receiver should the in fact average signal level of each bit on eight chips.This should carry out all bits among the ID (for example 128), is the signal of 10log (1024)=30dB for a signal to noise ratio average gain, should provide one 8 * 128=1024 the mean value in the sampling.For the more special circumstances that more expection labels and Geng Duo available channel (＞32) are arranged, this gain will increase.For 32 channels and 128 bits, can obtain the snr gain of 36dB.

Two-way conflict alleviates example

If the waveform sample that reader 100 storages obtain from the journey of front just may obtain bigger improvement aspect the time of accounting.By a stored waveform, a journey subsequently can be visited and be regarded as to the journey of front once more, by eliminating the conflict of front like this.This is in a single day not only all activities subsequently are all known because discerned a label, and the channels before all are selected and signal levels also should be known.

Consider example shown in Figure 24.During journey #1, label 1,3,5 and 7 is with bit pattern and channel level and phase identification.Alleviate according to the forward direction conflict, label 4 can be identified at journey #2, because the influence of label 1 and 5 can be removed from the conflict on the channel 0.Similarly, remove the influence of label 7 conflict from channel 4, thus identification label 6.At journey #2 with use after the forward direction conflict alleviates, label 1,3,4,5,6 and 7 just known.

Do not need the 3rd journey, can use the result who visits journey #1 after the forward direction conflict is delayed again.By at journey #2 identification label 4, just can from the channel as a result 2 of first journey of being stored, remove label 4, thereby analyze label 8.By at journey #2 identification label 6, just can from the result's of first journey of being stored channel 1, remove label 8, thereby analyze label 2.In this case, only need two journeys just can successfully discern all eight labels.When the channel that comprises and number of labels were bigger, the benefit that forward direction and two-way conflict alleviate just became more obvious.

Like this, described a simplex system that utilizes multipass transmission algorithm (adopting spread spectrum at last), this algorithm can provide premium properties (for example, time for reading and capacity).Conflict mitigation technique, dynamic channel configuration file and the combination that powers up scope have further improved systematic function.Described communication system has a lot of application, is not limited to described in this article preferred embodiment and example.The present invention can be applied in the user's set and network equipment of intercommunication system, active drive, and the substantive characteristics (described in the claim below) that does not break away from it.

Spirit or substantive characteristics that the present invention can not break away from it with other concrete forms enforcements.No matter from which side, described embodiment only should be counted as illustrative and not restrictive.Therefore scope of the present invention illustrates by the additional claim rather than the description of front.Within the equivalent intension of claim and scope change and be included within their spirit.

Claims

(according to the modification of the 19th of treaty)

1. method may further comprise the steps:

Store randomized tentation data;

Set up a channel and select configuration file, this configuration file comprises a plurality of channels selections, and wherein each channel selection is to concentrate from a son of this randomized tentation data to obtain; And

At least a portion at least one this randomized tentation data of first channel transmission of selecting from this channel to select the configuration file.

2. method as claimed in claim 1, wherein each channel selection is what to obtain from a unique subclass of this randomized tentation data.

3. method as claimed in claim 1 wherein begins this forwarding step after satisfying a predetermined condition.

4. method as claimed in claim 3 further comprises the step that receives a power level, wherein, satisfies this predetermined condition when this power level surpasses a predetermined threshold.

5. method as claimed in claim 1 further comprises step: stop this forwarding step when satisfying a predetermined condition.

6. method as claimed in claim 5 further comprises the step that receives a power level, wherein, satisfies this predetermined condition when this power level surpasses a predetermined threshold.

7. method as claimed in claim 5 further comprises the step that receives a power level, wherein, satisfies this predetermined condition when this power level is lower than a predetermined threshold.

8. method as claimed in claim 1, wherein select one first channel in the configuration file to select from one first channel group, to select at this channel, and select a second channel in the configuration file to select to select from a second channel group at this channel, wherein a plurality of channels in this first channel group are different from a plurality of channels in this second channel group.

9. (deletion)

10. method as claimed in claim 1, wherein, described tentation data be based in the following algorithm at least one come randomized: scrambling algorithm and cryptographic algorithm.

11. method as claimed in claim 1, wherein this forwarding step utilization is modulated frequently.

12. method as claimed in claim 1, wherein these a plurality of channels selections are equally distributed.

13. a device comprises:

Storage medium is used to store randomized tentation data;

Be coupled to the channel selector of this storage medium, be used to produce a channel and select configuration file, this channel selects configuration file to comprise a plurality of channels selections, and wherein each channel selection is to concentrate from a son of this randomized tentation data to obtain; And

Be coupled to the transmitter of this storage medium, be used for believing that from this at least one channel of selecting configuration file to select sends at least a portion of this randomized tentation data.

14. as the device of claim 13, wherein first channel of selecting to select the configuration file from this channel is orthogonal to a second channel of selecting from this channel selection configuration file.

15. as the device of claim 13, wherein the first channel standard of selecting to select the configuration file from this channel is orthogonal to a second channel of selecting from this channel selection configuration file.

16., wherein select specific lengthening pseudo noise sequence of a channel usage of selecting configuration file from this channel as the device of claim 13.

17. as the device of claim 13, wherein this device be following at least one: active device, and passive device.

18. system, comprise a plurality of first devices of communicating by letter with one second device, wherein each first device is stored randomized tentation data, set up a channel and select configuration file, this configuration file comprises a plurality of channels selections, and selecting configuration file at least one first channel selectively to send at least a portion of this randomized tentation data from this channel, and it is to concentrate from a son of this randomized tentation data to obtain that each channel is selected, and the individual at least first device synchronized transmission.

19. as the system of claim 18, wherein at least two first devices send simultaneously.

20. as the system of claim 18, wherein this second device is carried out a kind of conflict mitigation technique.

21. system as claim 18, wherein, at least one first device sends at least a portion of this randomized tentation data continuously on a channel of selecting to select the configuration file from this channel in a plurality of journeys, wherein select a new channel during each journey.

22. as the system of claim 21, wherein this second device is controlled the quantity of journey.

23. as the system of claim 21, wherein, before sending at least a portion of described randomized tentation data on described first channel of selecting, this second device is known the quantity of journey at described at least one first device.

24. a correlation technique may further comprise the steps:

Receive a burst;

Based on a predefined procedure this burst is reordered; And

This sequence that reorders is carried out a conversion.

25. as the method for claim 24, wherein this conversion is from a group selection, this group comprises: fast Hadamard transform (FHT), fast Walsh transform, fast Walsh-Hadamard transform.

26. as the method for claim 25, wherein this burst comprises at least one m sequence.

27. as the method for claim 26, wherein this predefined procedure is based on a generator polynomial of at least one m sequence.

28. as the method for claim 24, wherein this burst comprises the m sequence of at least one specific lengthening.

29. as the method for claim 28, wherein this predefined procedure is based on a generator polynomial of the m sequence of at least one specific lengthening.

30. as the method for claim 24, wherein the dimension of this conversion equals the quantity of available channel.

31. as the method for claim 24, wherein the dimension of this conversion is different from the quantity of available channel.

32. a device comprises:

Receiver is used to receive the element of a channel sequence;

State generator is used to produce an address sequence, so that conversion between pseudo noise sequence and Walsh sequence; And

Be coupled to the storage medium of this receiver and this state generator, be used for each element of signal being stored in a given address according to this address sequence.

33. as the device of claim 32, wherein this state generator comprises a linear feedback shift register.

34. as the device of claim 33, wherein this linear feedback shift register is a fibonacci sequence generator.

35. as the device of claim 32, wherein this state generator is second storage medium.

36. as the device of claim 32, wherein this pseudo noise sequence is a specific lengthening m sequence.

37. as the device of claim 32, further comprise the processor that is coupled to this storage medium, be used at least a portion of the element of this burst of being stored in this storage medium is carried out conversion.

38. as the device of claim 37, this conversion is from a group selection, this group comprises: fast Hadamard transform (FHT), fast Walsh transform, fast Walsh-Hadamard transform.

39. as the device of claim 32, wherein this receiver comprises an analog to digital converter.

40. a method for scrambling may further comprise the steps:

One group of data is divided into a first and a second portion;

First to these group data carries out first method for scrambling, with the first of the scrambling that produces data;

Revise the second portion of these group data with the first of the scrambling of these group data, with the second portion of the modification that produces these group data;

Second portion to the modification of these group data is carried out second method for scrambling, with the second portion of the scrambling that produces these group data; And

The first of revising the scrambling of these group data with the second portion of the scrambling of these group data.

41. as the method for scrambling of claim 40, wherein this first and second method for scrambling recursively enforcement of rights require 40 step, reach a predetermined length up to these group data.

42. as the method for scrambling of claim 41, wherein this predetermined length is a byte.

43., further comprise step:, just these group data are carried out a predefined function in case these group data reach this predetermined length as the method for scrambling of claim 41.

44. as the method for scrambling of claim 43, wherein this predefined function is an invertible function.

45. as the method for scrambling of claim 44, wherein this invertible function is one and searches function.

46. as the method for scrambling of claim 40, wherein the step of Xiu Gaiing is reversible.

47. as the method for scrambling of claim 40, wherein the step of Xiu Gaiing is to select from a group, this group comprises: XOR, modulus add and modulus subtracts.

48., further comprise step: this group scrambled data is programmed in the device as the method for scrambling of claim 40.

49. as the method for scrambling of claim 40, wherein this first and second method for scrambling is a cryptographic algorithm.

50. a de-scrambling method may further comprise the steps:

One group of data is divided into a first and a second portion;

The first of revising these group data with the second portion of these group data is with the first of the modification that produces these group data;

The second portion of these group data is carried out first de-scrambling method, with the second portion of the descrambling that produces these group data;

Revise the second portion of the descrambling of these group data with the first of the modification of these group data, with the second portion of the modification that produces these group data; And

First to the modification of these group data carries out second de-scrambling method.

51. as the de-scrambling method of claim 50, wherein this first and second descrambling part recursively enforcement of rights require 50 step, reach a predetermined length up to these group data.

52. as the de-scrambling method of claim 51, wherein this predetermined length is a byte.

53., further comprise step:, just these group data are carried out a predefined function in case these group data reach this predetermined length as the de-scrambling method of claim 51.

54. as the de-scrambling method of claim 53, wherein this predefined function is an invertible function.

55. as the de-scrambling method of claim 54, wherein this invertible function is one and searches function.

56. as the de-scrambling method of claim 50, wherein the step of Xiu Gaiing is reversible.

57. as the de-scrambling method of claim 50, wherein the step of Xiu Gaiing is to select from a group, this group comprises: XOR, modulus add and modulus subtracts.

58. a conflict that is used in the communication system alleviates method, the method comprising the steps of:

The signal that receives on first channel is estimated;

Determine to receive one group of channel of this signal in the above; And

Based on described estimation and determining step, from a plurality of signals that receive at second channel, remove this signal.

59. as the method for claim 58, wherein said estimating step comprises the received signal intensity of estimating this signal.

60. as the method for claim 58, wherein this estimating step is utilized error correction coding.

61. as the method for claim 58, wherein the step of claim 1 is repeated to carry out, up to having determined all signals.

62. as the method for claim 58, wherein this signal representative is stored at least a portion of the tentation data of a device.

63. as the method for claim 58, wherein this first channel is identical with second channel.

64. as the method for claim 58, wherein this first channel is different with second channel.

65. as the method for claim 58, wherein this first channel is orthogonal to this second channel.

66. as the method for claim 58, wherein this first channel standard is orthogonal to this second channel.

67. a conflict that is used in the multipass communication system alleviates method, this method may further comprise the steps:

In a given journey, the signal that receives on first channel is estimated;

Determine before and receive one group of channel of this signal in the journey subsequently thereon;

Based on described estimation and determining step, from a plurality of signals that receive at second channel, remove this signal.

68. as the method for claim 67, wherein, journey and one remove this signal at least one the journey subsequently before one.

69., further comprise step: in each journey, be stored in all signals that receive on their respective channel as the method for claim 67.

70. as the method for claim 67, wherein in each journey, multiple arrangement sends their corresponding signal to one common device on their selected channels.

71. as the method for claim 67, wherein this estimating step is utilized error correction coding.

72. as the method for claim 67, wherein the step of claim 67 is repeated to carry out, up to having determined all signals.

73. a conflict that is used in communication system alleviates method, this method may further comprise the steps:

Received signal on first channel;

Determine to receive one group of channel of this signal thereon; And

Based on this determining step, estimate signal sum in this system based on many known signals and many collision signals.

74. as the method for claim 73, wherein the step of claim 73 is repeated to carry out, and equals the estimated signals sum up to the quantity of known signal.

75. as the method for claim 73, wherein the step of claim 73 is repeated to carry out, up to reaching a predetermined level of confidence.

76. a method may further comprise the steps:

Received signal on a channel;

Estimate the variance of the absolute value of this signal; And

Based on this estimating step, when the variance of this estimation surpasses a predetermined threshold, determine on this channel, to have taken place a conflict.

77. as the method for claim 76, wherein this predetermined threshold is to obtain from a mean value of the absolute value of this signal.

78. a method may further comprise the steps:

Receive a CF signal;

Come this CF signal of continuous monitoring with first predetermined condition and second predetermined condition;

If satisfy this first predetermined condition, just send data;

If do not satisfy this first predetermined condition afterwards, just stopped the transmission of data;

If satisfy one second predetermined condition, just stop the transmission of data.

79., wherein when received power level surpasses a threshold value, satisfy this first predetermined condition as the method for claim 78.

80., wherein when received power level surpasses a threshold value, satisfy this second predetermined condition as the method for claim 78.

81., wherein when receiving a predetermined lock-out pulse, satisfy this first predetermined condition as the method for claim 78.

82. as the method for claim 78, wherein this first and second predetermined condition is arbitrarily.

83. at least one first device comprises:

Receiver is used to receive CF signal;

Be coupled to the monitor of this receiver, be used for this CF signal of continuous monitoring;

Storage medium wherein stores data; With

Be coupled to the transmitter of this receiver, this monitor and this memory, be used for when satisfying one first and second condition, sending at least a portion of these data.

84. as at least the first device of claim 83, wherein first and second conditions of first device are identical with first and second conditions of second device.

85. as at least the first device of claim 84, wherein this first and second device sends simultaneously.

86. as at least the first device of claim 83, wherein this first and second condition of first device is different with first and second conditions of second device.

87. as at least the first device of claim 86, wherein this first and second device sends simultaneously.

88. as at least the first device of claim 83, wherein at least one of this first and second condition is any appointment.

89. as at least the first device of claim 83, wherein at least one of this first and second condition is equally distributed.

90. at least the first device as claim 83 wherein when power level drops on a given range, satisfies this first and second condition.

Claims (90)

1. method may further comprise the steps:

Storing predetermined data;

Set up a channel and select configuration file, this configuration file comprises a plurality of channels selections, and wherein each channel selection is to concentrate from a son of this tentation data to obtain; And

At least a portion at least one this tentation data of first channel transmission of selecting from this channel to select the configuration file.

2. method as claimed in claim 1, wherein each channel selection is what to obtain from a unique subclass of this tentation data.

3. method as claimed in claim 1 wherein begins this forwarding step after satisfying a predetermined condition.

4. method as claimed in claim 3 further comprises the step that receives a power level, wherein, satisfies this predetermined condition when this power level surpasses a predetermined threshold.

5. method as claimed in claim 1 further comprises step: stop this forwarding step when satisfying a predetermined condition.

6. method as claimed in claim 5 further comprises the step that receives a power level, wherein, satisfies this predetermined condition when this power level surpasses a predetermined threshold.

7. method as claimed in claim 5 further comprises the step that receives a power level, wherein, satisfies this predetermined condition when this power level is lower than a predetermined threshold.

8. method as claimed in claim 1, wherein select one first channel in the configuration file to select from one first channel group, to select at this channel, and select a second channel in the configuration file to select to select from a second channel group at this channel, wherein a plurality of channels in this first channel group are different from a plurality of channels in this second channel group.

9. method as claimed in claim 1 further comprises step: this tentation data of randomization before setting up this channel selection configuration file.

10. method as claimed in claim 9, wherein this randomization step is based in the following algorithm at least one: scrambling algorithm, cryptographic algorithm.

11. method as claimed in claim 1, wherein this forwarding step utilizes band spectrum modulation.

12. method as claimed in claim 1, wherein these a plurality of channels selections are equally distributed.

13. a device comprises:

Storage medium is used for storing predetermined data;

Be coupled to the channel selector of this storage medium, be used to produce a channel and select configuration file, this channel selects configuration file to comprise a plurality of channels selections, and wherein each channel selection is to concentrate from a son of this tentation data to obtain; And

Be coupled to the transmitter of this storage medium, be used for believing that from this at least one channel of selecting configuration file to select sends at least a portion of this tentation data.

14. as the device of claim 13, wherein first channel of selecting to select the configuration file from this channel is orthogonal to a second channel of selecting from this channel selection configuration file.

15. as the device of claim 13, wherein the first channel standard of selecting to select the configuration file from this channel is orthogonal to a second channel of selecting from this channel selection configuration file.

16., wherein select specific lengthening pseudo noise sequence of a channel usage of selecting configuration file from this channel as the device of claim 13.

17. as the device of claim 13, wherein this device be following at least one: active device, and passive device.

18. system, comprise a plurality of first devices of communicating by letter with one second device, wherein each first the device storing predetermined data, set up a channel and select configuration file, this configuration file comprises a plurality of channels selections, and selecting configuration file at least one first channel selectively to send at least a portion of this tentation data from this channel, and each channel to select be to concentrate from a son of this tentation data to obtain, and at least two first device synchronized transmissions.

19. as the system of claim 18, wherein at least two first devices send simultaneously.

20. as the system of claim 18, wherein this second device is carried out a kind of conflict mitigation technique.

21. as the system of claim 18, wherein, at least one first device sends at least a portion of this tentation data continuously on a channel of selecting to select the configuration file from this channel in a plurality of journeys, wherein selects a new channel during each journey.

22. as the system of claim 21, wherein this second device is controlled the quantity of journey.

23. as the system of claim 21, wherein this second device is known the quantity of journey in advance.

24. a correlation technique may further comprise the steps:

Receive a burst;

Based on a predefined procedure this burst is reordered; And

This sequence that reorders is carried out a conversion.

25. as the method for claim 24, wherein this conversion is from a group selection, this group comprises: fast Hadamard transform (FHT), fast Walsh transform, fast Walsh-Hadamard transform.

26. as the method for claim 25, wherein this burst comprises at least one m sequence.

27. as the method for claim 26, wherein this predefined procedure is based on a generator polynomial of at least one m sequence.

28. as the method for claim 24, wherein this burst comprises the m sequence of at least one specific lengthening.

29. as the method for claim 28, wherein this predefined procedure is based on a generator polynomial of the m sequence of at least one specific lengthening.

30. as the method for claim 24, wherein the dimension of this conversion equals the quantity of available channel.

31. as the method for claim 24, wherein the dimension of this conversion is different from the quantity of available channel.

32. a device comprises:

Receiver is used to receive the element of a channel sequence;

State generator is used to produce an address sequence, so that conversion between pseudo noise sequence and Walsh sequence; And

Be coupled to the storage medium of this receiver and this state generator, be used for each element of signal being stored in a given address according to this address sequence.

33. as the device of claim 32, wherein this state generator comprises a linear feedback shift register.

34. as the device of claim 33, wherein this linear feedback shift register is a fibonacci sequence generator.

35. as the device of claim 32, wherein this state generator is second storage medium.

36. as the device of claim 32, wherein this pseudo noise sequence is a specific lengthening m sequence.

37. as the device of claim 32, further comprise the processor that is coupled to this storage medium, be used at least a portion of the element of this burst of being stored in this storage medium is carried out conversion.

38. as the device of claim 37, this conversion is from a group selection, this group comprises: fast Hadamard transform (FHT), fast Walsh transform, fast Walsh-Hadamard transform.

39. as the device of claim 32, wherein this receiver comprises an analog to digital converter.

40. a method for scrambling may further comprise the steps:

One group of data is divided into a first and a second portion;

First to these group data carries out first method for scrambling, with the first of the scrambling that produces data;

Revise the second portion of these group data with the first of the scrambling of these group data, with the second portion of the modification that produces these group data;

Second portion to the modification of these group data is carried out second method for scrambling, with the second portion of the scrambling that produces these group data; And

The first of revising the scrambling of these group data with the second portion of the scrambling of these group data.

41. as the method for scrambling of claim 40, wherein this first and second method for scrambling recursively enforcement of rights require 40 step, reach a predetermined length up to these group data.

42. as the method for scrambling of claim 41, wherein this predetermined length is a byte.

43., further comprise step:, just these group data are carried out a predefined function in case these group data reach this predetermined length as the method for scrambling of claim 41.

44. as the method for scrambling of claim 43, wherein this predefined function is an invertible function.

45. as the method for scrambling of claim 44, wherein this invertible function is one and searches function.

46. as the method for scrambling of claim 40, wherein the step of Xiu Gaiing is reversible.

47. as the method for scrambling of claim 40, wherein the step of Xiu Gaiing is to select from a group, this group comprises: XOR, modulus add and modulus subtracts.

48., further comprise step: this group scrambled data is programmed in the device as the method for scrambling of claim 40.

49. as the method for scrambling of claim 40, wherein this first and second method for scrambling is a cryptographic algorithm.

50. a de-scrambling method may further comprise the steps:

One group of data is divided into a first and a second portion;

The first of revising these group data with the second portion of these group data is with the first of the modification that produces these group data;

The second portion of these group data is carried out first de-scrambling method, with the second portion of the descrambling that produces these group data;

Revise the second portion of the descrambling of these group data with the first of the modification of these group data, with the second portion of the modification that produces these group data; And

First to the modification of these group data carries out second de-scrambling method.

51. as the de-scrambling method of claim 50, wherein this first and second descrambling part recursively enforcement of rights require 50 step, reach a predetermined length up to these group data.

52. as the de-scrambling method of claim 51, wherein this predetermined length is a byte.

53., further comprise step:, just these group data are carried out a predefined function in case these group data reach this predetermined length as the de-scrambling method of claim 51.

54. as the de-scrambling method of claim 53, wherein this predefined function is an invertible function.

55. as the de-scrambling method of claim 54, wherein this invertible function is one and searches function.

56. as the de-scrambling method of claim 50, wherein the step of Xiu Gaiing is reversible.

57. as the de-scrambling method of claim 50, wherein the step of Xiu Gaiing is to select from a group, this group comprises: XOR, modulus add and modulus subtracts.

58. a conflict that is used in the communication system alleviates method, the method comprising the steps of:

The signal that receives on first channel is estimated;

Determine to receive one group of channel of this signal in the above; And

Based on described estimation and determining step, from a plurality of signals that receive at second channel, remove this signal.

59. as the method for claim 58, wherein said estimating step comprises the received signal intensity of estimating this signal.

60. as the method for claim 58, wherein this estimating step is utilized error correction coding.

61. as the method for claim 58, wherein the step of claim 1 is repeated to carry out, up to having determined all signals.

62. as the method for claim 58, wherein this signal representative is stored at least a portion of the tentation data of a device.

63. as the method for claim 58, wherein this first channel is identical with second channel.

64. as the method for claim 58, wherein this first channel is different with second channel.

65. as the method for claim 58, wherein this first channel is orthogonal to this second channel.

66. as the method for claim 58, wherein this first channel standard is orthogonal to this second channel.

67. a conflict that is used in the multipass communication system alleviates method, this method may further comprise the steps:

In a given journey, the signal that receives on first channel is estimated;

Determine before and receive one group of channel of this signal in the journey subsequently thereon;

Based on described estimation and determining step, from a plurality of signals that receive at second channel, remove this signal.

68. as the method for claim 67, wherein, journey and one remove this signal at least one the journey subsequently before one.

69., further comprise step: in each journey, be stored in all signals that receive on their respective channel as the method for claim 67.

70. as the method for claim 67, wherein in each journey, multiple arrangement sends their corresponding signal to one common device on their selected channels.

71. as the method for claim 67, wherein this estimating step is utilized error correction coding.

72. as the method for claim 67, wherein the step of claim 67 is repeated to carry out, up to having determined all signals.

73. a conflict that is used in communication system alleviates method, this method may further comprise the steps:

Received signal on first channel;

Determine to receive one group of channel of this signal thereon; And

Based on this determining step, estimate signal sum in this system based on many known signals and many collision signals.

74. as the method for claim 73, wherein the step of claim 73 is repeated to carry out, and equals the estimated signals sum up to the quantity of known signal.

75. as the method for claim 73, wherein the step of claim 73 is repeated to carry out, up to reaching a predetermined level of confidence.

76. a method may further comprise the steps:

Received signal on a channel;

Estimate the variance of the absolute value of this signal; And

Based on this estimating step, when the variance of this estimation surpasses a predetermined threshold, determine on this channel, to have taken place a conflict.

77. as the method for claim 76, wherein this predetermined threshold is to obtain from a mean value of the absolute value of this signal.

78. a method may further comprise the steps:

Receive a CF signal;

Come this CF signal of continuous monitoring with first predetermined condition and second predetermined condition;

If satisfy this first predetermined condition, just send data;

If do not satisfy this first predetermined condition afterwards, just stopped the transmission of data;

If satisfy one second predetermined condition, just stop the transmission of data.

79., wherein when received power level surpasses a threshold value, satisfy this first predetermined condition as the method for claim 78.

80., wherein when received power level surpasses a threshold value, satisfy this second predetermined condition as the method for claim 78.

81., wherein when receiving a predetermined lock-out pulse, satisfy this first predetermined condition as the method for claim 78.

82. as the method for claim 78, wherein this first and second predetermined condition is arbitrarily.

83. at least one first device comprises:

Receiver is used to receive CF signal;

Be coupled to the monitor of this receiver, be used for this CF signal of continuous monitoring;

Storage medium wherein stores data; With

Be coupled to the transmitter of this receiver, this monitor and this memory, be used for when satisfying one first and second condition, sending at least a portion of these data.

84. as at least the first device of claim 83, wherein first and second conditions of first device are identical with first and second conditions of second device.

85. as at least the first device of claim 84, wherein this first and second device sends simultaneously.

86. as at least the first device of claim 83, wherein this first and second condition of first device is different with first and second conditions of second device.

87. as at least the first device of claim 86, wherein this first and second device sends simultaneously.

88. as at least the first device of claim 83, wherein at least one of this first and second condition is any appointment.

89. as at least the first device of claim 83, wherein at least one of this first and second condition is equally distributed.

90. at least the first device as claim 83 wherein when power level drops on a given range, satisfies this first and second condition.

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