CN108804027B - Compression storage method for single-bit specific bit time slot allocation table - Google Patents

A method of compressing a slot allocation table storing a single bit specific bit represented by a bit string is disclosed. The single bit positioning slot allocation table includes several code units, wherein one code unit is from a bit having a first bit value to all bits before the next bit having the first bit value. The compressed storage method comprises the steps that a single-bit time slot allocation table is divided into a plurality of sections of continuous data, so that each section of data has one code unit and the code units in two adjacent sections of data are different; and representing each piece of data by a start value, a repetition number value and a step value, wherein the start value represents the number of bits of a first bit in the piece of data in a one-bit specific time slot allocation table, the repetition number value represents the number of repetitions of a code unit in the piece of data, and the step value represents the number of bits having a second bit value in the code unit of the piece of data. The compression storage method of the invention can save the storage space of data.

Compression storage method for single-bit specific bit time slot allocation table

Technical Field

The present disclosure relates to the field of wireless communications, and more particularly, to data storage.

Background

The short-distance and high-precision wireless indoor positioning technology is widely applied to urban dense areas and indoor closed spaces. In the existing positioning system, positioning is mainly realized by adopting a mode that a positioning tag transmits a positioning signal and a positioning base station receives the positioning signal. The positioning system divides each positioning period into a plurality of positioning time slots, the positioning system allocates the positioning time slots for each positioning tag, the positioning tags transmit positioning signals in the positioning time slots where the positioning tags are located, and meanwhile, the positioning base station determines which positioning tag the positioning signals come from through the positioning time slots where the positioning signals are received, so that the positioning tags are positioned. The positioning time slots are distributed to the positioning tags, only one positioning tag in each positioning time slot in the same space to be positioned transmits a positioning signal, the positioning signal does not need to carry information of which positioning tag, and the positioning base station can judge which positioning tag the positioning base station belongs to according to the receiving time. The positioning tag obtains the positioning time slot to which the positioning tag belongs by storing a positioning time slot distribution table. Existing positioning tags store a positioning slot allocation table by a string of consecutive bit values, for example, a positioning tag stores a positioning slot allocation table of "010010", which indicates that the positioning tag transmits a positioning signal on the 2 nd and 5 th positioning slots. However, when the number of the positioning tags to be positioned is large or the positioning refresh rate of the positioning tags is high, there will be many positioning timeslots in a positioning cycle, so the length of the positioning timeslot allocation table will be long, and the positioning tags will spend a large storage space to store the positioning timeslot allocation table. For example, for a low-frequency location tag with a burst transmission frequency of 1200Hz, the storage length of the location timeslot allocation table is 1200 bits, i.e. 150 bytes; for a low-frequency positioning label with the pulse transmission frequency of 3000Hz, the storage length of a positioning time slot allocation table is 3000 bits, namely 375 bytes; and for the high-frequency positioning label with the pulse transmission frequency of 8000Hz, the storage length of the positioning time slot allocation table is 8000 bits, namely 1000 bytes. For the existing conventional positioning tag single chip microcomputer, the internal data storage area of the MCU is 1024 bytes. Therefore, when the burst transmission frequency of the positioning tag exceeds 8000Hz, it is difficult to store the positioning slot allocation table in the data storage area, and thus, the existing method of storing the positioning slot allocation table using the continuous bit value is no longer applicable.

In many application scenarios, in order to reduce the cost of the positioning tag, the storage space of the positioning tag is limited, and when the positioning timeslot allocation table is long, the positioning tag cannot store the positioning tag. Therefore, how to store the positioning slot allocation table in the positioning tag with limited storage space is an urgent problem to be solved by researchers in the field.

Disclosure of Invention

According to an aspect of the present invention, there is provided a method of compressed storage of a single-bit specific-bit slot allocation table represented by a bit string, wherein each bit has a first bit value or a second bit value, and wherein the single-bit specific-bit slot allocation table includes a plurality of code units, wherein one code unit is from a bit having the first bit value to all bits before a next bit having the first bit value, the method of compressed storage comprising: dividing the single bit positioning time slot allocation table into N sections of continuous data so that each section of data has one code unit and the code units in two adjacent sections of data are different; each piece of data is represented by a start value, a repetition number value and a step value, wherein the start value represents the number of bits of a first bit in the piece of data in a one-bit specific time slot allocation table, the repetition number value represents the number of repetitions of a code unit in the piece of data, and the step value represents the number of bits having a second bit value in the code unit of the piece of data.

The invention has the advantages that the positioning time slot table stored in a single bit mode is compressed by utilizing a segmented storage mode, the storage space is greatly reduced under the condition of larger data, and the hardware cost of a positioning system is saved.

Drawings

Fig. 1 is a schematic diagram of a location slot allocation table in a location tag MS according to an embodiment of the present invention;

Detailed Description

Specific embodiments of the present invention will be described in detail below, and it should be noted that the embodiments described herein are only for illustration and are not intended to limit the present invention. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one of ordinary skill in the art that: it is not necessary to employ these specific details to practice the present invention. In other instances, well-known circuits, materials, or methods have not been described in detail in order to avoid obscuring the present invention.

Throughout the specification, reference to "one embodiment," "an embodiment," "one example," or "an example" means: the particular features, structures, or characteristics described in connection with the embodiment or example are included in at least one embodiment of the invention. Thus, the appearances of the phrases "in one embodiment," "in an embodiment," "one example" or "an example" in various places throughout this specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, or characteristics may be combined in any suitable combination and/or sub-combination in one or more embodiments or examples. Further, those of ordinary skill in the art will appreciate that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements present. Like reference numerals refer to like elements. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Fig. 1 shows a schematic storage diagram of a location slot allocation table in a location tag MS according to an embodiment of the present invention. The method for storing the positioning time slot allocation table shown in fig. 1 divides an original positioning time slot allocation table stored in a single-bit manner into a plurality of sections for compression storage. The positioning time slot allocation table stores the allocation condition of the positioning time slot in a positioning period, in a single-bit storage mode, each bit has a first bit value or a second bit value, a stored value of one bit represents whether a positioning time slot belongs to a current positioning tag MS, wherein the first bit value represents that the positioning time slot corresponding to the stored value belongs to the current positioning tag MS, the positioning tag transmits a positioning signal in the positioning time slot, the second bit value represents that the positioning time slot corresponding to the stored value does not belong to the current positioning tag MS, and the positioning tag does not transmit the positioning signal in the positioning time slot. In one embodiment, the first bit value is "1", which represents that the location time slot corresponding to the stored value belongs to the current location tag MS, and the location tag transmits a location signal in the location time slot; the second bit value is "0", which represents that the positioning time slot corresponding to the stored value does not belong to the current positioning tag MS, and the positioning tag does not transmit a positioning signal in the positioning time slot. Of course, it should be understood by those skilled in the art that in another embodiment, the first bit value may also be "0", which represents that the location time slot corresponding to the stored value does not belong to the current location tag MS, and the location tag does not transmit the location signal in the location time slot, and the second bit value is "1", which represents that the location time slot corresponding to the stored value belongs to the current location tag MS, and the location tag transmits the location signal in the location time slot.

In the storage method of the positioning time slot allocation table shown in fig. 1, a single-bit positioning time slot allocation table is divided into N segments of continuous data so that each segment of data has one code unit and the code units in two adjacent segments of data are different; and representing each piece of data by a start value, a repetition number value and a step value, wherein the start value represents the number of bits of a first bit in the piece of data in a one-bit specific time slot allocation table, the repetition number value represents the number of repetitions of a code unit in the piece of data, and the step value represents the number of bits having a second bit value in the code unit of the piece of data.

To more clearly illustrate the above method for storing the location slot allocation table, the following data of a location slot allocation table in a single-bit storage mode are provided: "00100001000010010010010001" is taken as an example, the data includes code units 10000, 100, 1000 and 1, and the data can be divided into 4 continuous data segments according to that each segment of data has one code unit and the code units in two adjacent segments of data are different, which respectively are: 1000010000, 100100100, 1000, and 1. The 4 pieces of data are represented by a start value, a repetition number value and a step value, the start value represents the number of bits of the first bit in the piece of data in the one-bit specific bit slot allocation table, the repetition number value represents the number of repetitions of the code unit in the piece of data, and the step value represents the number of bits having the second bit value in the code unit of the piece of data, in this embodiment, the first bit value takes 1 and the second bit value takes 0, so that the following storage result [4] [ 342 ] [ 1323 ] [ 2231 ] [ 2601 ] is obtained. The first bracket [ ] stores the number of segments, and the subsequent brackets [ ] store the data of one segment, which are the starting value a, the number of steps s, and the number of repetitions t. The starting value ai of the ith paragraph is a (i-1) + (s (i-1) +1) × t (i-1), where a (i-1) denotes the starting value of the ith-1 paragraph, s (i-1) denotes the number of steps of the ith-1 paragraph, and t (i-1) denotes the number of repetitions of the ith-1 paragraph, and where i is an integer greater than 1. For segment 1, the starting value is the position of the first occurrence of the value "1" in one positioning cycle. For example, in the above example, the position of the first occurrence value "1" is the 3 rd bit in the single-bit data storage mode, and therefore, the start value of the 1 st segment is 3.

In the above embodiment, the positioning tag MS first stores therein the total number of data segments N of the positioning slot allocation table, which indicates that N segments of data are stored in the next data storage space. Next, N pieces of data of the positioning slot allocation table are stored, wherein each piece of data includes three parts, which are a start value, a step number, and a repetition number. Taking the ith segment as an example, the start value ai represents that the data stored in the ith segment is data starting from the second ai position of the positioning time slot allocation table in the single-bit storage mode, and the value of the second ai position is "1", that is, the positioning tag MS needs to transmit the positioning signal in the second ai positioning time slot. The step number si indicates that the positioning slot allocation table has si bits with a value of "0" after the second ai position in the single-bit storage mode, i.e. the positioning tag MS does not need to transmit a positioning signal in the second ai +1 to the third ai + si positioning slots. The number of repetitions ti represents the number of repetitions of the values of the positions ai to ai + si of the positioning slot allocation table in the single-bit storage mode in the immediately following positioning slot allocation table data. In one embodiment, the storage space size of the segment number, the start value, the step number, and/or the repetition number may be determined according to the length of one positioning period, for example, the segment number, the start value, the step number, and/or the repetition number occupy two bytes in one embodiment.

In one embodiment, the number of segments n is 1, and the positioning slot allocation tables are evenly distributed throughout the length.

By adopting the storage method, the positioning time slot allocation table stored in the original single-bit mode is compressed, and when the data volume of the positioning time slot allocation table is large, the storage space can be effectively reduced, or more time slot table information can be represented on the limited storage space. For example, for a high-frequency positioning tag with a burst transmission frequency of 8000Hz, in the conventional continuous bit value storage method, the storage length of the positioning time slot allocation table is 1000 bytes, whereas with the positioning time slot allocation table storage method of the present invention, the positioning time slot allocation table can be stored with a minimum of 6 bytes.

step 201: comparing the current positioning time slot number x with the initial value of each segment in the positioning time slot allocation table, and finding a segment number value i which enables the ai to be more than or equal to x to be more than or equal to a (i + 1);

step 202: calculating the result u of the remainder obtained by dividing the current positioning time slot number x minus the ith initial value ai by the ith stepping number si plus 1, wherein the result u is (x-ai)% (si + 1);

step 204: the current positioning time slot belongs to a positioning tag MS, and the positioning tag MS transmits a positioning signal in the current positioning time slot;

step 205: the current positioning time slot does not belong to a positioning tag MS, and the positioning tag MS does not transmit a positioning signal in the current positioning time slot;

step 206: entering a next positioning time slot, and adding 1 to the number x of the positioning time slots;

step 208: entering the next positioning period, the number x of positioning slots is counted from 1.

The invention discloses a storage and analysis method of a positioning time slot table of a positioning label, which compresses the positioning time slot table stored in a single-bit mode by utilizing a segmented storage mode and provides a corresponding positioning time slot table analysis method.

As noted above, while the preferred embodiments of the invention have been illustrated and described, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiments. Rather, the invention should be determined entirely by reference to the claims that follow.