JP2792197B2 - Relay method of spread spectrum synchronization signal - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a relay system of a spread spectrum synchronization signal, and in particular, a spread spectrum synchronization signal transmitted by a frequency hopping type relay station does not collide with each other, and The present invention relates to a method of relaying a spread spectrum synchronization signal which is made to be dependent on a master station or a higher-order relay station without being dependent on a relay station.

[Conventional technology]

Spread Spectrum (Spread Spectru) using the frequency hopping (HF)
m, hereafter abbreviated as SS) is well known. SS is used to improve S / N by using a much wider bandwidth than necessary when transmitting information, and HF is a type of SS system that uses a large number of preset frequencies. Next, the transmission frequency is pseudo-randomly selected to be a broadband signal subjected to spread spectrum. The transmission frequency is selected such that a frequency corresponding to a certain code state of a pseudo-random code sequence whose probability of occurrence is normally selected, and another frequency is selected for another code state. Defines the frequency of the carrier, and thus the carrier frequency hops between frequencies in synchronization with the change in the code state.

In a radio communication network using this type of FH SS, it is important to match the code timing between the transmitting and receiving systems, that is, synchronization is important.Conventionally, when relaying an SS synchronization signal for this purpose, the relay station must By relaying at different transmission timings assigned in advance, collision with the SS synchronization signal transmitted by the master station or another relay station is avoided.

[Problems to be solved by the invention]

In the above-described conventional SS synchronization signal relay, when relaying an SS synchronization signal, the relay station relays at different transmission timings assigned in advance, thereby causing collision with the SS synchronization signal transmitted by the master station or another relay station. , But each SS
Since there is no distinction in the synchronization signal, there is a disadvantage that the relay station that should originally be subordinate to the master station or the higher-order relay station receives the SS synchronization signal of the lower-level relay station and becomes subordinate to the synchronization system of the main station. . The hierarchized hierarchies corresponding to the operational priorities assigned to the at least one repeater in advance are hierarchized as temporal priorities in the relay processing.

[Means for solving the problem]

The method of the present invention is a method of relaying a spread spectrum synchronization signal in a wireless communication network in which communication is performed between a main station and an end station via at least one relay station by a spread spectrum modulation method based on frequency hopping. Means for allocating the transmission timing of the spread spectrum synchronization signal to a hierarchy hierarchized in accordance with an operational priority previously assigned to each of the at least one relay station, and hierarchical information from the received spread spectrum synchronization signal. Means for extracting and confirming a match or mismatch with a layer to which the own station belongs, which is assigned in advance for each of the repeaters,
Means for relaying the spread spectrum synchronizing signal to a lower relay station or terminal station at a pre-assigned transmission timing in the own station hierarchy for each repeater.

Further, the method of the present invention has a configuration in which a hierarchy hierarchized corresponding to an operational priority assigned in advance to each of the at least one repeater is hierarchized as a temporal priority in relay processing. Have.

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of one embodiment of the present invention. In the embodiment shown in FIG. 1, super-frame information 4 as frame information of the received SS synchronization signal 2 to the SS synchronization signal 2,
The transmitted hierarchical information 5 and the (initial synchronization) reference signal 6
If there is an SS synchronization signal coming in after the initial synchronization, and if there is an SS synchronization signal of an upper station, 12 reference signals 7 for correcting the synchronization (synchronization correction) to the above-described reference signal 6 for the initial synchronization are output. A synchronous control circuit 1, a time base 8 for outputting a time-based clock signal 11, a super-frame counter 9 for outputting a super-frame timing signal, a hierarchical counter 10 for outputting a hierarchical timing signal 13, A transmission control circuit 14 for monitoring the timing signal 12 and the hierarchical timing signal 12 and checking whether the superframe timing signal of the local station matches the hierarchical information, and an SS synchronization signal for generating and outputting an SS synchronization signal 18 to be transmitted to the transmission side. And a signal generation circuit 17.

FIG. 2 shows a transmission format of the SS synchronization signal in the embodiment of FIG. Figure 2 is an example where the hierarchy is three, the symbol S ₀ is SS synchronizing signal frame main station, S _1, S ₂ hierarchy
1, S ₃ and S ₄ indicate the layer 2 and S ₅ indicate the SS synchronization signal frame of the layer 3. T is the transmission period of the SS synchronization signal, and t is the period of the SS synchronization signal including all layers, that is, the superframe synchronization. FIG. 2 shows the SS synchronization signal frame of layer 2
It is shown also shown the configuration content of the SS synchronizing signal of the main station, which is forwarded to S _3.

 Next, the operation of the embodiment shown in FIG. 1 will be described.

In FIG. 1, in the case of initial synchronization, the synchronization control circuit 1 extracts layer information and superframe information from the received SS synchronization signal 2 and compares them with its own station layer information 3 which is set in advance. If it is a signal, the extracted layer information 4 and superframe information 5 are set in the layer counter 10 and superframe counter 9 respectively, and the time base 8, superframe counter 9 and layer counter 10 are reset simultaneously with the reference signal 6 to make them dependent. Synchronize.

If the SS synchronization signal is received after the initial synchronization,
The hierarchy is compared, and if the signal is the SS synchronization signal of the upper station, the synchronization is corrected by resetting the time base 8 simultaneously with the reference signal 7. The super frame counter 9 counts the clock signal 11 and outputs a super frame timing signal 12. The layer counter 10 counts the superframe timing signal 12 and outputs a layer timing signal 13.

The transmission control circuit 14 monitors the super-frame timing signal 12 and the hierarchical timing signal 13 and, if it matches the preset local station hierarchical information 3 and the local super-frame information 15, sets the transmission control signal 16 to the SS synchronization signal generating circuit. Output to 17.

The SS synchronizing signal generation circuit 17 generates an SS synchronizing signal in which the local station hierarchy information 3 and the local superframe information 15 are inserted, and transmits the transmission synchronizing signal 16 and the transmission SS synchronizing signal 18 to the transmitting side at the same time.

FIG. 3 (a) is a diagram showing an example of an operation state in the embodiment of FIG. 1, and FIG. 3 (b) is an explanatory diagram of the operation contents of FIG. 3 (a).

3 (a) and 3 (b), an example is a wireless communication network in which the master station 101 transmits to the terminal station 104 via the two relay stations A102 and the relay station B103 by the FH modulation method. Is hierarchy 1,
Relay station B103 is assigned a hierarchy 2, SS synchronization signal transmitted from the master station 101 is sent by the SS synchronizing signal frame S _0,
RS A102 receiving this sends to the relay station B102 in the SS synchronization frame S ₁ hierarchy 1. Although the relay station B103 receiving this sends to the terminal station 104 by using the SS synchronizing signal frame S ₃ of the hierarchy 2 in this transfer sequence, as indicated by X marks P, relay station A102 is the hierarchy 1 This indicates that they do not depend on the SS synchronization signal of the relay station B103 belonging to the layer 2 because they belong to the layer 2.

In this way, the collision of the SS synchronization signal is avoided, and the relay station that is to follow the master station or the higher-order relay station deviates from the synchronization system of the main station depending on the SS synchronization signal of the lower-level relay station. Is suppressed.

〔The invention's effect〕

As described above, according to the present invention, the transmission timing of the SS synchronization signal is hierarchized and assigned for relaying, layer information is extracted from the received SS synchronization signal, and the SS synchronization signal is automatically compared with the pre-assigned own layer. By relaying at a pre-assigned transmission timing in the station hierarchy, it is possible to avoid collision with the SS synchronization signal transmitted by the master station and other relay stations, and do not depend on lower-order relay stations, and There is an effect that slave synchronization can be performed only to a higher relay station.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention, FIG. 2 is a transmission format of an SS synchronization signal in the embodiment of FIG. 1, and FIG. 3 (a) is an operation in the embodiment of FIG. FIG. 3B is a diagram showing an example of the state, and FIG. 3B is an explanatory diagram of the operation content of FIG. 3A. DESCRIPTION OF SYMBOLS 1 ... Synchronization control circuit, 2 ... Reception SS synchronization signal, 3 ... Local station hierarchy information, 4 ... Superframe information, 5 ... Higher hierarchy etc., 6 ... Reference signal (initial synchronization), 7 ... Reference signal (synchronization correction), 8 time base, 9 superframe counter, 10 hierarchical counter, 11 clock signal, 12 superframe timing signal, 13 hierarchical timing signal, 14 transmission control circuit, 15 transmission control circuit
Own station super frame signal, 16: transmission control signal, 17: SS synchronization signal generation circuit, 18: transmission SS synchronization signal.

Claims (2)

(57) [Claims] 1. A method for relaying a spread spectrum synchronization signal in a wireless communication network for communicating between a main station and an end station via at least one relay station in a spread spectrum modulation system by frequency hopping. Means for assigning the transmission timing of the spread spectrum synchronization signal to a hierarchy hierarchized in accordance with an operational priority assigned to each of the at least one relay station, and hierarchical information from the received spread spectrum synchronization signal. Means for extracting and confirming a match or mismatch with a layer to which the own station assigned in advance for each repeater belongs, and transmitting the spread spectrum synchronization signal at a pre-assigned transmission timing in the own station layer for each repeater. Spread spectrum comprising means for relaying to a lower relay station or terminal station. Relay system of the period signal. 2. The method according to claim 1, wherein the hierarchical layers corresponding to the operational priorities assigned in advance to the at least one repeater are hierarchized as temporal priorities in the relay processing. 2. A relay system for a spread spectrum synchronization signal according to claim 1.