TWI416965B - Method and system for increasing the transmitting efficiency of a wireless network by using the distance information - Google Patents

Abstract

A method for increasing the transmitting efficiency of a wireless network by using the distance information is disclosed. The method includes the following steps. Many spectrums of a major transmission pair are detected to check whether there exists empty spectrum or not. At least one pseudo-carrier is transmitted from the transmitter of a minor transmission pair for estimating the cognitive information of the spectrum. At least one permissible space is selected from the spectrums based on the cognitive information, and the limitations of the permissible space are figured out. The major transmission pair is checked to compromise the releasing of the permissible spaces. A best channel is selected from the permissible spaces based on the limitations. The power, modulation and code rate of the minor transmission pair are adapted to satisfy the limitation of the best channel. The best channel is assigned to the minor transmission pair for signal transmitting.

Description

Method and system for increasing network transmission efficiency by using distance information in wireless network

The present invention relates to a wireless communication technology, and more particularly to a wireless communication technology that shares a spectrum band.

The wireless communication band is a limited resource and is regulated by relevant government regulations. In order to maximize the efficiency of using this resource, common practices in the industry include: 1. Control power to divide the space covered by the wireless communication band, such as a cellular system. 2. Increase the resolution of the codec to increase the information load of the single spectrum band.

In addition, in addition to statically increasing the information capacity of the fixed transmission band to meet the needs of multiple signal transmission and reception technologies, there is a technology for dynamically distributing the white spectrum band to the required signal transmission and reception pair.

However, if a main signal transceiving pair is occupied by a plurality of spectrum bands that are statically allocated, and no extra white spectrum band is provided to the sub-signal transceiving pair, the pair of signal transceiving pairs only waits until white. The spectrum band is given up for use.

Therefore, one technical aspect of the present disclosure is to provide a method for increasing network transmission performance by using distance information in a wireless network, so as to realize the use of non-white spectrum bands to meet communication requirements.

According to an embodiment of the present invention, a method for increasing network transmission performance by using a distance message in a wireless network is provided, which includes the following steps: first, detecting a plurality of spectrum bands of a transmission channel of a main transceiver pair, and determining whether There is a white spectrum band, and if so, a pair of transceiver pairs are directly transmitted for signal transmission. If not, the following steps are performed. Next, at least one dummy carrier signal is transmitted from the secondary transceiver to the transmitting end to the receiving end to estimate the sensing information of each spectrum band. Then, based on the perceptual information, it is judged whether each spectrum band is an allowable space and an allowable parameter of each allowable space. Thereafter, it is confirmed that the primary transceiver pair compromises to provide these allowed spaces to the secondary transceiver pair. Then, according to these allowable parameters, the optimal transmission channel of the sub-transceiver pair is selected from the allowable space. Then, the transmission power and signal mode of the secondary transceiver pair are adjusted to meet the limit of the allowable parameters of the optimal transmission channel. Finally, the best transmission channel can be used for sub-transmission and signal transmission.

In addition, according to other embodiments of the present technical aspect, the sensing information is information such as an average value and a variation of a signal noise ratio in a spectrum band, a rate of a transmission signal of the main transceiver pair, and an outbound probability. The allowed space is a spectrum band that satisfies a transmission rate threshold and a transmission quality threshold; and the transmission quality threshold is an allowable signal error rate and an outbound probability. It is worth noting that adjusting the transmission power of the secondary transceiver pair is based on the strength of the dummy carrier signal.

Another aspect of the present disclosure is to provide a system for increasing network transmission performance by using distance information in a wireless network, to more effectively utilize a limited wireless spectrum band, and to serve as many signal transceiving pairs as possible.

According to an embodiment of the present invention, a system for increasing network transmission performance by using a distance message in a wireless network is provided, including a primary wireless signal transceiving pair and at least one pair of wireless signal transceiving pairs. The sub-wireless transceiver pair performs the method of increasing the network transmission performance by using the distance information in the wireless network as described above to share the spectrum band of the main wireless signal transceiving pair.

Therefore, the foregoing embodiments enable the sub-signal transceiver pair to share the spectrum band for transmission without affecting the transmission operation of the main signal transceiver pair, without being limited to the provision of the white spectrum band.

Please refer to FIG. 1. FIG. 1 is a flow chart showing the steps of a method for increasing network transmission performance by using a distance message in a wireless network according to an embodiment of the present disclosure. In the first figure, the method comprises the following steps: First, as described in steps 101 and 102, spectrum sensing is performed, which measures whether the spectrum that can be used in each segment is white spectrum (White spectrum). The white spectrum represents the spectrum without any user. If all the frequency bands are not white spectrum, which means that there is no completely blank frequency band, then the following steps 103-106 are performed: next, as described in step 103, a transmit pseudo-carrier is transmitted; the dummy carrier is one type not included. The electronic signal of any amount of information is similar in form to a harmonic. The purpose of transmitting harmonics is to detect if the sub-transceiver transmits a signal with such signal strength, whether there is a change in the data transmission rate already existing in the main transceiving pair, and an estimation of the perceived information amount. Then, as described in step 104, Estimate cognitive information is included; the sensing information includes an average value of the signal-to-interference ratio of the secondary transceiver to the receiving end, a variation, a data rate of the currently existing primary transceiver pair, and an out-of-boundary probability. The signal interference ratio is defined as follows:

The numerator P0'(d0,0) in the above equation represents the intensity of the signal to be received. The strength of this signal is a function of the distance d0,0; the denominator P1'(d1,0),...,Pk' in the above equation (dk, 0) represents the received signal strength of other existing transmission and reception pairs, and the k existing transmission reception pairs represent interference signals.

Next, as shown in step 105, it is found out which permissible space can be shared with the secondary transceiver pair. A three-dimensional space set that can support the same transmission rate and quality (error rate and out-of-bound probability) is called an allowable space. Judging which of the allowed spaces means that the maximum transmission rate can be known and a certain transmission quality bit is satisfied in space. What location. In addition, as shown in step 106, it is also confirmed whether the main transceiver pair compromises (compromise agreed) to give up the allowable space to the secondary transceiver pair without affecting the normal operation of the master transceiver pair. If not, return to step 103 to retransmit the dummy carrier to find a new shared spectrum band.

After finding the allowed space of the main transceiver pair compromise, as shown in step 107, the best channel can be selected; after all the transmittable frequency bands are estimated to correspond to the allowed space, select one. It can support the frequency band with the highest transmission rate, and can determine that the interference of the newly added sub-transmission pair to the existing main transceiver pair and even other sub-transceiver pairs when transmitting with such power can be allowed or tolerated.

Finally, as shown in steps 108 and 109, the newly added sub-transceiver pair needs to adapt to the transmit power (adapt transmit power); and, because the pseudo-carrier is tested when selecting the allowable space, the newly added sub-transceiver pair finally selects The transmit power is the maximum false carrier strength. In the same way, the newly added sub-transceiver pair also needs to adjust the adapt modulation and code rate, that is, select an appropriate modulation method (for example: BPSK, QPSK, 16QAM, 64QAM) and coding. Combine to form different data rates. Then, the secondary transceiver pair can start data transmission.

In summary, the present embodiment is a method for increasing the performance of a network by using a cognitive network or a cognitive network (Cognitive Radio Network), which refers to a transmission and reception pair on the network. That is, the transmission rate of the Transmit-Receive pair. Overall, the present embodiment estimates some necessary information at the receiving end (Receiver), which includes the average value (Mean) and variance (Variance) of the signal-to-interference ratio at the receiving end. The transmission rate of other users and the required signal-to-interference ratio, Outage Probability, and then use this information to select the best channel.

Therefore, the present embodiment can appropriately adjust the transmission power and the transmission rate, so that the multiple transmission and reception pairs are satisfied with the respective transmission quality, and thus the overall transmission rate of the entire wireless network can be improved compared with the conventional network. The average value and the number of variations of the signal interference ratio are related to the power of the transmitting end, the statistical characteristics of the channel, and the distance between the opposite transmitting receivers. In other words, the present embodiment utilizes information related to distance to increase network performance.

Please refer to FIG. 2 . FIG. 2 is a schematic structural diagram of a system for increasing network transmission performance by using a distance message in a wireless network according to an embodiment of the present disclosure. In the system 200, the signal of the main signal transceiving pair 210 covers the range 201, which is represented by a semi-ellipse or an ellipse, and the actual electric wave coverage range is an irregular shape. The system 200 includes a primary signal transceiving pair 210 (PS-Tx0 and PS-Rx0) and K sub-signal transceiving pairs 220. These sub-signal transceiving pairs 220 are perceptual transmitting and receiving pairs (CR TR pair 1, ..., CR TR Pair K). It is worth noting that the transmitting and receiving ends of these sub-signal transceivers 220 can be randomly dispersed in the space. The main signal transceiving pair 210 is the most primitive user in the network, and the sub-signal transceiver pair 220 is a newly added transmitting and receiving pair. Except for the main signal transceiving pair 210, all the sub-signals newly added to the wireless network system 200 are transceived. For the 220, the method for increasing the network transmission performance by using the distance information in the wireless network in the foregoing embodiment is required. Taking FIG. 2 as an example, the wireless network system 200 includes a primary signal transmission and reception pair 210, which is a primary transmission and reception pair (PS TR pair, Primary system transmit-receive pair), and K sub-signal transceiver pairs 220. CR TR pair (cognitive radio TR pair). Here, the K sub-signal transceiver pairs 220 are located on different floors of the same building, but the actual application may not be limited thereto.

Furthermore, taking FIG. 2 as an example, a system 200 has been originally established by the primary transceiver pair 210 and its signal coverage range 201; the system 200 may already have several secondary transceiver pairs 220, that is, the primary transceiver pair One or more spectral bands used by 210 are shared with these pairs of transceivers 220. At this time, if a new secondary transceiver pair 220 wants to join the system 200, it must go through two levels of consideration: first, the newly added secondary transceiver pair 220 cannot destroy the original working state of the existing system 200. That is, a plurality of allowed spaces can be selected for the sub-transceiver pair 220 in the spectrum bands of the main transceiver pair 210. The second is that these allowable spaces must meet the signal transmission requirements of the secondary transceiver pair 220, including power considerations, signal to noise ratios, and resolution. Therefore, the secondary transceiver pair 220 can complete the above two levels of consideration according to the teachings of the embodiment.

Technically, when the secondary transceiver pair 220 is to be added to the system 200, the foregoing steps 101-105 are performed, which is to find the allowed space from the spectrum bands of the primary transceiver pair 210, and the allowable space is to satisfy the secondary transceiver pair 220. The spectral band of the transmission rate threshold and the transmission quality threshold, that is, the allowable space, allows the signal transmission rate or quality of the secondary transceiver pair 220 to be above the lower limit of the secondary transceiver pair 220 itself. Specifically, the transmission quality threshold, that is, the transmission quality requirement, is usually an allowable signal error rate and an out-of-bound probability. Of course, since the allowed space is tested by the sub-transceiver pair 220 with the pseudo-carrier transmitted by the step 103, the transmission power of the sub-transceiver pair is limited to the intensity of the dummy carrier signal in the subsequent step 108. It should be noted that only the channel that the secondary transceiver pair 220 can use is selected from the spectrum band of the primary transceiver pair 210; in this embodiment, it is still required to confirm that the secondary transceiver pair 220 is not added as shown in step 106. Destroy the original transmission mechanism of the primary transceiver pair 210.

Please refer to Figure 3, which is a diagram of the transmission signal simulation test of the system of Figure 2. Figure 3 assumes that the system of Figure 2 simulates the transmission rate of the traditional sensing network (without the method shown in Figure 1) and the total system using the method shown in Figure 1 with K = 1. Comparison of transmission rates. The relationship between the relative distance and the transmission rate is shown in FIG. 3, wherein the label (Ours) represents the simulation result of the present embodiment, and the label (Conventional CRN) is the simulation result of the conventional sensing network. The horizontal axis represents the distance between the primary signal transmitting and receiving pair 210 (PS0 T-R pair) and the secondary signal transmitting and receiving pair 220 (CR1 T-R pair).

In Fig. 3, the line at the center position represents the transmission rate of the main signal transceiving pair 210, the line at the lower position represents the transmission rate of the sub-signal transceiver pair 220, and the line at the upper position represents the combination of the two, and the central line It represents the transmission rate of the traditional cognitive network. Obviously, after the physical distance between the two is greater than or equal to 10 meters, the total transmission rate of the sensing network in this embodiment may be significantly exceeded than the traditional sensing network in which the embodiment is not implemented.

The present invention has been disclosed in the above embodiments, and is not intended to limit the present invention. Any one of ordinary skill in the art to which the present invention pertains may make various changes and modifications without departing from the spirit and scope of the invention. The scope of protection of the present invention is therefore defined by the scope of the appended claims.

101-109. . . step

200. . . system

201. . . Signal coverage

210. . . Main signal transmission and reception

220. . . Secondary signal transmission and reception

The above and other objects, features, advantages and embodiments of the present invention will become more apparent and understood.

1 is a flow chart showing the steps of a method for increasing network transmission performance by using a distance message in a wireless network according to an embodiment of the present disclosure.

FIG. 2 is a schematic structural diagram of a system for increasing network transmission performance by using a distance message in a wireless network according to an embodiment of the present disclosure.

Figure 3 is a diagram of the transmission signal simulation test of the system of Figure 2.

101-109. . . step

Claims (7)

A method for increasing network transmission performance by using a distance message in a wireless network, comprising: detecting a plurality of spectrum bands of a transmission channel of a main transceiver pair, determining whether a white spectrum band exists, and if so, directly transmitting and receiving a pair of signals For signal transmission, if not, the following steps are performed; at least one dummy carrier signal is transmitted from the secondary transceiver to the transmitting end to the receiving end to estimate the sensing information of each spectrum band; and each spectrum band is judged according to the sensing information. Whether it is an allowable space, and an allowable parameter of each allowable space; confirm that the main transceiver pair compromises to provide the allowable space to the pair of transceivers; and according to the allowable parameters, select the pair of the pair of transceivers from the allowable spaces a transmission channel; adjusting a transmission power and a signal mode of the sub-transceiver pair to meet the limit of the allowable parameter of the optimal transmission channel; and performing the sub-transmission and transmission signal transmission by using the optimal transmission channel. The method of claim 1, wherein the sensing information is used to increase network transmission performance in a wireless network, wherein the sensing information is an average value and a variance of a signal to noise ratio in the spectrum band. The method of claim 1, wherein the method for increasing the network transmission performance by using the distance information in the wireless network, wherein the sensing information is a rate and an outbound probability of the transmission signal of the main transceiver pair in the spectrum band. A method for increasing network transmission performance by using a distance message in a wireless network as claimed in claim 1, wherein the allowed space is a spectrum band that satisfies a transmission rate threshold and a transmission quality threshold. The method for increasing network transmission performance by using a distance message in a wireless network as described in claim 4, wherein the transmission quality threshold is an allowable signal error rate and an outbound probability. The method for increasing network transmission performance by using a distance message in a wireless network according to claim 1, wherein adjusting the transmission power of the pair of transceivers is based on an upper limit of the strength of the dummy carrier signal. A system for increasing network transmission performance by using a distance message in a wireless network, comprising: a primary wireless signal transceiving pair; and at least one pair of wireless signal transceiving pairs for performing the wireless network as claimed in claim 1 The method of using the distance information to increase the network transmission performance to share the spectrum band of the main wireless signal transceiver pair.