JPH0448007B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a wireless communication system in which a base station and a mobile station are connected, perform a channel search during standby, and use one of them to conduct a call when transitioning from standby to talk. In particular, it relates to a multi-channel search method used in cordless telephones and the like. [Prior Art] Conventionally, this type of channel search has been carried out by searching each channel in order and storing empty channels in memory, or by scanning channels at random and storing only empty channels. . [Problems to be solved by the invention] In the conventional empty channel search method described above,
When searching for a channel, if consecutive channels are empty channels, they will be stored as empty channels.In wireless systems for cordless phones and other small zones, other cordless phones in the same zone will be able to search for the consecutive empty channels. When communication is carried out on one of the channels, if an interfering signal is detected adjacent to the communication channel, the interference causes interference in the communication channel. In addition, channels adjacent to the channel in which the interference signal has entered are subject to interference by the interference signal, and what should have been an empty channel is determined to be a used channel, which has the disadvantage of hindering the effective use of the channel. Therefore, the present invention seeks to provide an empty channel search method that does not cause interference in communication channels and does not hinder the effective use of channels. [Means for Solving the Problems] In order to solve the above problems, the present invention divides the memory into a plurality of areas that do not interfere with each other, and utilizes the non-interference property. That is, in the empty channel search method according to the present invention, when both the base station and the mobile station are on standby, a channel search is performed and an empty channel is stored in a memory, and when the standby mode changes to a call mode, the stored empty channel is scanned. In a multi-channel access wireless communication system in which a call is made using one of the channels, the memory is divided into at least two areas whose stored contents do not interfere with each other, and the memory is divided into at least two areas with free space in the at least two areas. The storage of the channels is repeated in order for each region, so that channels spaced apart by at least two channels are stored in adjacent memory elements in each region, and the scanning is repeated until an empty channel is found. This is repeated in order for each channel group. [Example] Next, the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an example of the overall configuration between a base station and a mobile station in which the present invention can be implemented, in which 1 is a wireless section of the base station, 2 is a control section of the base station, and 3 is for wireless communication. 4 is a mobile station antenna, 5 is a mobile station control unit, and 6 is a mobile station radio unit for wireless communication.Both the base and mobile station perform channel scanning in standby mode, and Memorize the channel. Now, if we decide to make a call on one of the empty channels in which the call signal from the mobile station is stored, the base station searches for and captures the call signal from the mobile station, and the mobile station paired with the base station After confirming whether the signal is from the station, a call will be made on this channel. For both base stations and mobile stations, the channel designation of the radio section is controlled by their respective control sections.
By configuring an ID (identification) signal within the calling signal, it is possible to determine whether the signal is a desired signal or an interfering signal. In this example, the number of usable channels is 40. In the control units 2 and 5, the memory for recording empty channels is divided into three areas having approximately the same number of memory elements, and the empty channels stored in memory elements in different areas between the areas are as follows: Even if the two channels are adjacent to each other, they are configured so as not to interfere with each other. On the other hand, the channels used are also divided into three groups. And 1, 4, 7,...40 channels (14 channels in total)
Channels, mutual spacing 2 channels) are set as the first group in the first area divided as above, and similarly, 2, 5, 8, ... 38 channels in total, 13 channels are set as the second group. Channels 3, 6, 9, . . . 39 are set as a third group in the third region. FIG. 2 is a diagram showing the above configuration,

[0]
represents all channels to be used, [],
[] and [] are the first, second, and
and the third group, respectively. Note that the first, second, and third areas of the memory also correspond to the above-mentioned [], [], and [], respectively. In the above configuration, when both the base station and the mobile station are in standby and scan channels and store empty channels in memory, if consecutive empty channels are
If channels 0 to 28 continue, empty channels are set as 10, 13, 16,...28, and the first
memory in the area. The same goes for storing the second and third channel groups [2] and [3] in the second and third memory areas, respectively, and empty channels are stored in each group. Next, when scanning this memory, the first memory area is first scanned in the order of channels 1, 4, 7, . Since each channel is separated by two channels within this area, there is no interference from other channels in the readout call, and no interference is caused to others. 2, 5 in the second memory area on the other hand,
Channels 8, 11, ... are all adjacent to each other in terms of channel order, but since the areas are formed so that there is no interference between the areas, no interference actually occurs. do not have. The above applies to the second channel group (memory area) and the third channel group.
The same applies between channel groups (memory areas). In the above, three memory areas are used, the same as the number of channel groups, but the third memory area can also be omitted. In this case, the effective use of channels will decrease slightly, but it is relatively unlikely that the third channel group will become vacant when all of the first and second channel groups are not vacant, so this is not a big problem. . Further, in the above embodiment, the channel spacing is set to two channels, which poses no problem in practice; however, if the channel spacing is set to three or more channels, the mutual interference will be further reduced. That is, for example, the first channel group [] is set to channels 1, 5, 9, 13, ..., the second channel group [2] is set to channels 2, 6, 9, 13, ..., and the third channel group is set to channels 3. , 7, 11, ... channels, and the fourth channel group is 4, 8, 1.
2. It may also be a channel. Also, the fourth memory area may be eliminated. If the channel spacing is further increased, mutual interference will be further reduced, but the division of memory areas will become somewhat more complicated. Although it is ideal that the plurality of channel regions are arranged in an orderly manner, the arrangement is not limited to this, and one region may be divided. The point is that there should be no interference between regions. [Effects of the Invention] As explained above, according to the present invention, since adjacent channels have an interval of at least two channels, interference between channels can be sufficiently eliminated, and therefore channel efficiency can be improved. It is possible to aim for

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of a configuration diagram regarding a wireless communication system between a base station and a mobile station in which the present invention can be implemented;
FIG. 2 is a diagram for explaining an embodiment of a 40-channel empty channel search method. Explanation of symbols: 1 represents a wireless section, 2 represents a control section, 5 represents a control section, 6 represents a wireless section, and [], [], and [] represent channel group numbers, respectively. Note that the numbers 1, 2, 3, . . . 40 in FIG. 2 represent channel numbers.

Claims (1)

[Claims] 1 Both the base station and the mobile station perform a channel search and store empty channels in memory when in standby mode, and when switching from standby mode to call mode, scan the stored empty channels and use one of them to make a call. In a multi-channel access wireless communication system that performs
storage of empty channels in the at least two areas is repeated for each area in order, and at this time, channels spaced apart by at least two channels are stored in adjacent memory elements in each area. An empty channel search method characterized in that the scanning is repeated in order for each channel group until an empty channel is found.