CN101163126A - Method of implementing QPSK modulation using 16QAM modulation - Google Patents

Abstract

The invention discloses a method of achieving QPSK modulation through using 16QAM modulation, including the following steps: sign data is stored after completing WCDMA downlink symbol processing; the four-bit b3b2b1b0 of QPSK modulation main channel is expanded to 00b1b0 and 00b3b2 respectively, and then 16QAM modulation is carried out respectively; the four-bit b3b2b1b0 of QPSK modulation diversity channel is expanded to eight-bit b0b100b2b300, and then 16QAM modulation is carried out. The method of the invention can achieve QPSK modulation through using 16QAM. As for HSPDSCH channel and HS-SCCH channel of HSPDA, the invention can achieve chip-level processing of HSPDSCH channel and HS-SCCH channel by using a set of 32-fold clock time division multiplexing hardware resources. Compared with the prior technical proposal, the method can save a set of 32-fold time division multiplexing hardware resources.

Description

A kind of method that realizes the QPSK modulation with the 16QAM modulation

Technical field

The present invention relates to 3-G (Generation Three mobile communication system), specifically, the method that relates to the baseband chip level processing of the 16QAM modulation (16 ary quadrature amplitude) of 2 kinds of modulation systems of a kind of Wideband Code Division Multiple Access (WCDMA) (WCDMA) and QPSK modulation (quarternary phase-shift keying (QPSK) modulation) physical channel.

Background technology

WCDMA is one of main flow system of the third generation (3G) mobile communication system.Wherein the HSDPA of R5 version proposition (High Speed Downlink Packet Access, high speed downlink packet inserts) technology has become current research focus.The HSDPA technology is to realize improving the of paramount importance technology of WCDMA network high-speed downlink message transmission rate, be that 3GPP puts forward in order to satisfy the asymmetric demand of up-downgoing data service in the R5 agreement, it can be on the basis that does not change the WCDMA system network architecture of having built, improve user's downstream data traffic speed greatly, can reach more than the 10Mbps, this technology is to improve a kind of important technology of downlink capacity and data service rate in the WCDMA networking.

In order to realize the functional characteristic of HSDPA, three down physical channel: HS-DSCH, HS-SCCH and HS-DPCH (High-Speed Dedicated Physical Control Channel) in the 3GPP physical layer specification, have been introduced.Wherein HS-DSCH (high speed descending sharing channel) is used for UMTS (Universal mobile terrestrialsystem) communication system carries downlink user data.HS-DSCH (HSPDSCH) channel has 2 kinds of modulation system: QPSK modulation and 16QAM modulation, and the HS-SCCH channel has only a kind of modulation system QPSK modulation.

Fig. 1 has provided the WCDMA down channel is handled antenna transmission from symbol level process.101 is that the symbol level of down physical channel is handled among Fig. 1, and the symbol level of HS-DSCH channel is handled and mainly comprised CRC (cyclic redundancy check (CRC)), bit scramble, and chnnel coding (tubro coding), bit collection and physical channel interweave etc.The symbol level of HS-SCCH channel is handled and is mainly comprised chnnel coding, rate-matched etc.Handle at the down channel symbol level, the HS-DSCH channel can have 15 physical channels at most, and the HS-SCCH channel has 14 physical channels at most.Every physical channel carries out after processing through 102 chip-levels among Fig. 1, passes through then the processing of 103 intermediate frequencies and radio frequency among Fig. 1, sends among the wireless environment.

Fig. 2 has provided the processing method of the chip-level of every descending physical channel, and every down physical channel is divided into main collection and 2 channels of diversity again among the WCDMA system, and main collection is identical with the processing procedure of diversity, and just the generation of symbol is inequality before the spectrum-spreading and scrambling.201 is-symbol levels among Fig. 2 are handled the symbol of a later physical channel, the processing of main collection channel does not need through 202 STTD coding among Fig. 2, diversity channel then will be through the STTD coding, main collection is identical with the processing of diversity then, through 203 modulation mappings among Fig. 2, be divided into I road and Q road, again through 204 and 205 carrying out respectively spread spectrum among Fig. 2, carry out scrambling through 206 among Fig. 2 again, 207 power weightings among the data process Fig. 2 after the scrambling.Cut position add up after 29 all Channel Processing are complete later on again by sending after 103 processing among Fig. 1.

Fig. 3 has provided the planisphere of QPSK modulation and 16QAM modulation, and 2 bits of QPSK modulation (wherein low bit is corresponding to the bit of sending out earlier) are corresponding to a symbol, and 4 bits of 16QAM modulation (wherein low bit is corresponding to the bit of sending out earlier) are corresponding to 1 symbol.

Fig. 4 has provided the method for the STTD of QPSK modulation diversity in the WCDMA system, and the bit of per 4 QPSK modulation carries out the STTD coding.

Fig. 5 has provided the method for the STTD of 16QAM modulation diversity in the WCDMA system, and the bit of per 8 16QAM modulation carries out the STTD coding.

As can be seen from Figure 4 and Figure 5, the main collection of QPSK modulation and 16QAM modulation is different with the production method of diversity, in the WCDMA system, 15 HS-DSCH channels and 14 HS-SCCH channels all will be supported in each sub-district, and the HS-DSCH channel can be supported QPSK and 16QAM modulation system.

From top 2 kinds different modulation systems, in existing techniques in realizing following defective is arranged:

(1) if realizes at the clock of 32 times of hardware using, and be that time division multiplexing realizes Channel Processing, then a cover hardware resource can be handled 32 physical channels, because 16QAM modulation and QPSK modulation system is different, then to handle as different channels, then needing the number of the actual channel handled in the system is 44 (15 * 2+14), then need 2 cover hardware resources to realize, and the physical channel QPSK of HSPDSH modulates and the 16QAM modulation can not exist simultaneously, can cause the waste of hardware resource.

(2) if the system clock (clock frequency is 245.76Mhz) of 64 times of hardware using realize, and adopt time-multiplexed method to realize Channel Processing, then can realize with a cover hardware resource, but because clock frequency is too high, hardware is realized relatively difficulty, and also causes the waste of hardware resource.

Summary of the invention

Technical problem to be solved by this invention is the defective of above-mentioned existence in the prior art, characteristics for QPSK modulation and 16QAM modulation, the QPSK modulation is processed as a kind of special situation of 16QAM modulation, QPSK and 16QAM process as a kind of channel, and the time-multiplexed resource of clock that a cover is 32 times finishes the HSPDSCH channel and HS-SCCH channel code chip level is processed.

The present invention specifically is achieved in that

A kind of method with 16QAM modulation realization QPSK modulation comprises the following steps:

The first step after the descending symbol level of WCDMA is finished dealing with, is stored symbol data;

Second step is for main 4 bit b that collect channel of QPSK modulation ₃b ₂b ₁b ₀, expand to respectively 00b ₁b ₀And 00b ₃b ₂, carry out respectively then the 16QAM modulation;

The 3rd step is for 4 bit b of the diversity channel of QPSK modulation ₃b ₂b ₁b ₀, expand to 8 bit b ₀b ₁00b ₂b ₃00, carry out then the 16QAM modulation.

Described second step comprises,

Step 1, from the data of having stored, read 8 bits, b ₇b ₆b ₅b ₄b ₃b ₂b ₁b ₀, per 2 bits are one group and carry out spectrum-spreading and scrambling;

Step 2, earlier with b ₁b ₀Adjustment expands to 4 bit 00b through symbol ₁b ₀, carry out subsequently the 16QAM modulation;

Step 3, handle b ₁b ₀After, repeating step 2 is finished b ₃b ₂, b ₅b ₄, b ₇b ₆Processing.

Repeating step 1-3 all handles up to all data of channel.

Described the 3rd step, when processing main collection antenna data, second step carries out, comprise,

Step 1, from the data of having stored, read 8 bits, b ₇b ₆b ₅b ₄b ₃b ₂b ₁b ₀, to b ₃b ₂b ₁b ₀Be extended to 00b ₃b ₂00b ₁b ₀

Step 2, to the expansion after 00b ₃b ₂00b ₁b ₀Carry out the STTD coding according to the method for 16QAMSTTD coding;

Step 3, earlier low four of 8 Bit datas behind the coding are carried out the 16QAM modulation, after finishing dealing with, again the Gao Siwei to 8 Bit datas behind the coding is carried out the 16QAM modulation;

Step 4, repeating step 1-3 finish b ₇b ₆b ₅b ₄Processing.

Repeating step 1-4 all handles up to all data of channel.

The present invention is by above-mentioned method, can modulate by 16QAM and realize the QPSK modulation, HSPDSCH channel and HS-SCCH channel for HSPDA, by can realize the chip-level processing of HSPDSCH channel and HS-SCCH channel once 32 times of time-multiplexed hardware resources of clock of cover, just can save the hardware resource of the time-multiplexed 32 times of clocks of 1 cover with respect to existing technical scheme.

For other channel that QPSK modulation and 16QAM modulation are arranged simultaneously, can adopt top method equally, the hardware resource of half be can save, thereby circuit area and hardware resource greatly reduced.

Description of drawings

Fig. 1 is a WCDMA down channel handling process;

Fig. 2 is WCDMA down channel chip-level processing figure;

Fig. 3 is the planisphere of QPSK modulation and 16QAM modulation;

Fig. 4 is the STTD coding of QPSK modulation;

Fig. 5 is the STTD coding of 16QAM modulating mode;

Fig. 6 is the unified modulation constellation of QPSK and 16QAM;

Fig. 7 is the block diagram that the 16QAM modulation realizes the QPSK modulation.

Embodiment

Below in conjunction with accompanying drawing, method embodiment of the present invention is carried out comparatively detailed explanation.

For the down physical channel of the modulation system of 16QAM, 16QAM modulation factor 0.4472 merges to by DSP among the initial power of this channel, and 16QAM modulation and QPSK modulate and just can be unified among Fig. 6 like this.

Fig. 7 is a block diagram of the present invention, wherein 701 be the HSPDSCH channel after symbol level is finished dealing with to store among the read-write 8 bit width RAM of twoport, the modulating mode of HSPDSCH channel has 2 kinds: QPSK modulation and 16QAM modulation, 2 kinds of modulating modes can only be selected a kind of modulation system in the subframe of a 2ms, modulation system for QPSK, a physical channel is 960 bits at the bit number of a time slot (2ms/3), for the 16QAM modulation system, a physical channel is 1920 bits at the bit number of a time slot.The physical channel number of HSPDSCH channel is 15 at most.The modulating mode of HS-SCCH channel has only the QPSK modulation, and the bit number of a HS-SCCH physical channel is 40, and the number of HS-SCCH channel mostly is 14 most.

Owing to will realize that total number of HSPDSCH channel and HS-SCCH channel mostly is 29 most, and the spreading rate in the WCDMA system is 3.84M, can adopt 32 times clock 122.88M to come time division multiplexing to realize 29 above channels, the 1st cycle of 32 times of clocks is corresponding to physical channel 1, the 2nd cycle of 32 times of clocks is corresponding to physical channel 2, the rest may be inferred, and the 32nd cycle of 32 times of clocks is corresponding to physical channel 32.HSPDSCH channel occupancy 1 to 16 channel, HS-SCCH channel occupancy channel 17 to 32.

32 channel time division multiplexes are processed, and in fact hardware resource only has 1 cover, processing structure such as Fig. 7 of hardware, and the main collection of each physical channel support and diversity antenna, main collection and diversity antenna are separately processed, and comprise the symbol adjustment, modulation mapping, spectrum-spreading and scrambling and power weightings.

For the HS-SCCH channel, each sequential of each physical channel only has 40 bits, and spreading factor is that 128,1 sequential (2560 chips) send, and per 512 chips of HS-SCCH channel read 8 bits, b from dual port RAM ₇b ₆b ₅b ₄b ₃b ₂b ₁b ₀, collecting antenna for HS-SCCH channel master, per 2 bits are one group and carry out spectrum-spreading and scrambling that send at first is b ₁b ₀, b ₁b ₀Expand to 4 bit 00b through the symbol adjustment in 702 ₁b ₀, so have producing the symbol on I road and Q road through 703 according to the modulation mapping method among Fig. 6, carrying out spread spectrum and scrambling then, process b ₁b ₀Carrying out b later on ₃b ₂, the like.

In the data of processing main collection antenna simultaneously, for the data of diversity antenna, earlier in 705 to b ₃b ₂b ₁b ₀Be extended to 00b ₃b ₂00b ₁b ₀, the method for the coding of the 16QAMSTTD in 706 is carried out the STTD coding then, supposes that the bit behind the STTD coding is a ₇a ₆a ₅a ₄a ₃a ₂a ₁a ₀, then earlier to a ₃a ₂a ₁a ₀Produce the symbol on I road and Q road according to the method at the sound of the modulation among Fig. 6 in 707, the data behind the coding are carried out spectrum-spreading and scrambling and power weightings in 708, and a finishes dealing with ₃a ₂a ₁a ₀Processing a later on ₇a ₆a ₅a ₄, a ₇a ₆a ₅a ₄Processing b after handling ₇b ₆b ₅b ₄After 8 bit process are finished, reading next 8 bits, all handling up to the 40 all bits of this channel.

For the HSPDSCH channel, modulation system can be QPSK modulation and 16QAM modulation.In the situation of QPSK modulation, the total number of bits of each physical channel is 960, and spreading factor is 16, and per 64 chip read the 8bit data, and the processing of 8 Bit data masters collection and diversity is consistent with the processing of diversity with the main collection of HS-SCCH channel.

For the 16QAM modulation system, the middle bit number of each physical channel is 1920, and spreading factor is 16, and per 32 chip read the 8bit data b ₇b ₆b ₅b ₄b ₃b ₂b ₁b ₀, owing to be 16QAM modulation, main collection is processed earlier 703 earlier to b ₃b ₂b ₁b ₀Modulate mapping, in 704, carry out then spectrum-spreading and scrambling and power weightings, handle b ₃b ₂b ₁b ₀Processing b later on ₇b ₆b ₅b ₄

When processing main collection, diversity b ₇b ₆b ₅b ₄b ₃b ₂b ₁b ₀In 706, carry out the STTD coding of 16QAM, suppose that the bit behind the STTD coding is a ₇a ₆a ₅a ₄a ₃a ₂a ₁a ₀, then earlier to a ₃a ₂a ₁a ₀Method according to the mapping of the modulation among Fig. 6 in 707 produces the symbol on I road and Q road, and the data behind the coding are carried out spectrum-spreading and scrambling and power weightings in 708, and a finishes dealing with ₃a ₂a ₁a ₀Processing a later on ₇a ₆a ₅a ₄After 8 bit process are finished, reading next 8 bits, all handling up to the 1920 all bits of this channel.

After 29 all Channel Processing are intact at the cut position that adds up, the later data of cut position by antenna transmission among wireless environment.

Such scheme can be applied in the HSDPA system fully, realizes in the mode of FPGA hardware, accomplishes real-time processing.

The front provides the description of detailed embodiment, so that any technical staff of this area can use or utilize the present invention.Various modifications to these embodiment are evident for personnel skilled in the art.Thereby, the embodiment shown in the invention is not restricted to here, and the wide region of principle that should disclose and feature according to meeting here.

Claims (5)

1. the method with 16QAM modulation realization QPSK modulation is characterized in that, comprises the steps:

The first step after the descending symbol level of WCDMA is finished dealing with, is stored symbol data;

Second step is for main 4 bit b that collect channel of QPSK modulation ₃b ₂b ₁b ₀, expand to respectively 00b ₁b ₀And 00b ₃b ₂, carry out respectively then the 16QAM modulation;

The 3rd step is for 4 bit b of the diversity channel of QPSK modulation ₃b ₂b ₁b ₀, expand to 8 bit b ₀b ₁00b ₂b ₃00, carry out then the 16QAM modulation.

2. the method for the QPSK modulation that realizes with 16QAM modulation as claimed in claim 1 is characterized in that:

Described second step comprises,

Step 1, from the data of having stored, read 8 bits, b ₇b ₆b ₅b ₄b ₃b ₂b ₁b ₀, per 2 bits are one group and carry out spectrum-spreading and scrambling;

Step 2, earlier with b ₁b ₀Adjustment expands to 4 bit 00b through symbol ₁b ₀, carry out subsequently the 16QAM modulation;

Step 3, handle b ₁b ₀After, repeating step 2 is finished b ₃b ₂, b ₅b ₄, b ₇b ₆Processing.

3. the method for the QPSK modulation that realizes with 16QAM modulation as claimed in claim 2 is characterized in that:

Repeating step 1-3 all handles up to all data of channel.

4. the method for the QPSK modulation that realizes with 16QAM modulation as claimed in claim 1 is characterized in that:

Described the 3rd step, when processing main collection antenna data, second step carries out, comprise,

Step 1, from the data of having stored, read 8 bits, b ₇b ₆b ₅b ₄b ₃b ₂b ₁b ₀, to b ₃b ₂b ₁b ₀Be extended to 00b ₃b ₂00b ₁b ₀

Step 2, to the expansion after 00b ₃b ₂00b ₁b ₀Carry out the STTD coding according to the method for 16QAMSTTD coding;

Step 3, earlier low four of 8 Bit datas behind the coding are carried out the 16QAM modulation, after finishing dealing with, again the Gao Siwei to 8 Bit datas behind the coding is carried out the 16QAM modulation;

Step 4, repeating step 1-3 finish b ₇b ₆b ₅b ₄Processing.

5. the method for the QPSK modulation that realizes with 16QAM modulation as claimed in claim 4 is characterized in that:

Repeating step 1-4 all handles up to all data of channel.

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