JP2004538668A - Method and apparatus for acquiring a channel in a wireless spread spectrum communication system - Google Patents

Abstract

Briefly, the wireless communication device (200) includes at least one receiver channel element (212), such as a receiver finger, that receives a broadcast channel and a forward pilot signal. The wireless communication device (200) also includes a non-broadcast channel capture module (216) that determines whether the non-broadcast channel is initially captureable, such as a suitably programmed processing device. If the non-broadcast channel cannot be acquired, the non-broadcast channel acquisition module (216) determines whether the forward pilot signal associated with the non-broadcast channel is of acceptable quality. This may be based on, for example, the energy level of the pilot signal and the symbol error rate of the received information, or other suitable criteria. The non-broadcast channel acquisition module (216) may also provide for non-broadcast to a transmitter such as a BTS if the forward pilot signal is of acceptable quality prior to a predetermined timeout period. The transmission power of the communication channel is increased to signal that non-broadcast channel acquisition is facilitated. Thus, the wireless communication device does not need to wait for a predetermined timeout period to receive a plurality of allowable consecutive frames.

Description

[0001]
(Cross-reference of co-pending applications)
This application is entitled "Method and Apparatus for Changing Receiver Finger Assignments," entitled Dino et al., Owned by a common assignee, filed on the same day, and incorporated herein by reference. Related to co-pending application at Attorney Case No. CE08413R, Application No. 09 / 552,093.
[0002]
(Industrial applications)
The present invention relates generally to digital wireless communication systems, and more particularly, to a method and apparatus for acquiring a channel in a code division multiple access (CDMA) communication system.
[0003]
(Conventional technology)
For example, 3GPPS C.I. commonly known as Third Generation Partnership 2 S00002-A (CDMA2000) and IS95 TIA / EIA-95B Mobile Station-Base Station Compatibility Standard for Dual Mode Spread Spectrum Communication System A wireless spread-spectrum communication system or other suitable communication system generally properly captures non-broadcast channels to transmit voice, data or other information to mobile stations, base station radios (e.g. A mobile station is required to be able to communicate with a BTS) or other transmitter. Non-broadcast channels include traffic channels, control channels, or other channels that are not broadcast to other mobile stations. Generally, mobile stations such as radiotelephones, Internet appliances, laptop computers or other suitable communication devices first establish a broadcast pilot channel that they receive from one or more BTSs. Attempt capture. The synchronization channel is then generally transmitted by the BTS and received by the mobile station. In addition, an overhead paging message is communicated by the BTS over the paging channel and received by the mobile station. The mobile station can then send an origination message to the BTS, which then sends a channel assignment message to the mobile station via the paging channel. This channel assignment message includes the assigned channel, such as a Walsh code or other suitable spreading code information. The mobile station then attempts to properly acquire the assigned non-broadcast channel (eg, traffic channel) based on the channel assignment message. Thus, the transition to a non-broadcast channel generally occurs after a channel assignment message. In general, transitioning to a traffic channel requires at least three concurrent tasks.
[0004]
For example, a mobile station must provide a decoder and a combiner for an assigned channel and wait for a traffic frame. The decoder may include multiple rake receiver fingers. A searcher, such as a search receiver, finds the peak energy of the assigned traffic channel and provides that information to the finger management entity, which assigns the assigned traffic channel, such as a Walsh code. Assign the spreading code of the channel to receiver fingers that are already locked to the existing forward pilot channel. The searcher detects the best peak in the forward pilot signal, and then passes the detected peak information to a finger management entity that assigns receiver fingers to lock to the good peak. However, while the forward pilot energy may be high enough to show a good peak, the traffic channel energy from the BTS may be too low, so that the receiver fingers lock onto the commanded signal. Before being able to do so, the mobile station may not be able to receive a good frame. However, existing systems have not attempted to incorporate non-broadcast channel (such as traffic and control channels) acquisition techniques to address these and other problems. Instead, conventional systems generally do not determine why an unacceptable acquisition frame has been received, but instead the mobile station must wait for a configured timeout period (after which time the mobile station It only requires the mobile station to wait to return to the acquisition state). Further, the mobile station starts transmitting the reverse pilot signal to the BTS. When a mobile station transitions to an assigned traffic channel or control channel, the mobile station generally needs to ensure that communication between the BTS and the mobile station over the assigned channel is steady. . According to IS95-Section 6.6.4.2, this occurs when a mobile station receives two consecutive traffic channel frames within a 200 millisecond latency. If the mobile station does not receive two consecutive good frames, it waits for two consecutive good frames for 200 ms and then returns to the forward pilot channel substate.
[0005]
However, waiting for a plurality of consecutive good frames within a predetermined waiting time may unnecessarily waste time capturing a non-broadcast channel. Further, in a CDMA2000 type system using a fast closed loop transmit power control scheme, the forward pilot signal energy may not accurately represent the traffic channel energy. The fast closed loop power control scheme generally allows the BTS to instruct the mobile station to increase or decrease the transmit power and the mobile station informs the BTS to increase or decrease the transmit power. Enable. Such a closed loop power control scheme allows, for example, to adjust the downlink power hundreds of times per second. Thus, the pilot energy measurement may not accurately represent the traffic channel energy or the control channel energy due to the fast energy changes caused by the fast closed loop power control. For example, if the mobile station sends transmission power control information, such as power control bits (PCB), to the base station every 1.25 milliseconds, this control information is transmitted to the base station by a specific It may be required to increase or decrease the traffic channel power of the traffic channel very frequently.
[0006]
Thus, there is a need for a non-broadcast channel acquisition method and wireless communication device that appropriately reduces the latency of acquiring a channel. It would further be desirable if such a method and apparatus could determine why a good non-broadcast channel frame was not received.
[0007]
(Description of the preferred embodiment)
Briefly, a wireless communication device includes at least one receiver channel element, such as a receiver finger that receives a non-broadcast channel and a forward pilot signal. The wireless communication device also includes a non-broadcast channel capture module, such as a suitably programmed processing device, that determines whether the non-broadcast channel is initially captureable. If the non-broadcast channel cannot be acquired, the non-broadcast channel acquisition module determines whether the forward pilot signal associated with the non-broadcast channel is of acceptable quality. This can be done, for example, based on the energy level of the pilot signal and the symbol error rate of the received information, or other suitable criteria. The non-broadcast channel acquisition module may also increase the non-broadcast channel transmission power to a transmitter, such as a BTS, if the forward pilot signal is of acceptable quality, for a predetermined period of time. Prior to expiration, it is signaled to facilitate non-broadcast channel acquisition. Thus, the wireless communication device does not need to wait for a predetermined period of time to receive a plurality of consecutive frames, but instead sends the transmit power control information to the transmitter to provide a non-broadcast channel acquisition procedure. During this time, it may be requested to increase the power transmission.
[0008]
Also disclosed is a method that includes reducing a non-broadcast channel acquisition latency in response to detecting a bad received frame. The method determines, for example, whether a receiver channel element, such as a receiver finger, is still locked to a forward pilot signal after detection of a bad frame, and determines whether the receiver channel element is a forward pilot signal. If still locked to the signal, this can be done by detecting that the pilot energy is acceptable. If a bad frame is still detected, the method increases the transmit power of the assigned channel to the transmitter, such as the base transmitter, to facilitate channel acquisition during the channel acquisition procedure. Informing the user to do so.
[0009]
FIG. 1 shows a spread spectrum communication system, such as a code division multiple access (CDMA) communication system 100, which is a mobile station capable of communicating with one or more base station wireless devices, shown as base stations 104a through 104n. 102a to 102n. CDMA communication system 100 transmits and receives spread spectrum signals. For purposes of illustration and not limitation, the present invention is entitled, for example, "Physical Layer Standard for CDMA2000 Spread Spectrum Systems" (3GPP2 C.S0002-A) version 55; 3gpp2. It will be described with reference to a CDMA2000 cellular system as described in specifications available at org and incorporated herein by reference. However, those skilled in the art will recognize that the methods and apparatus of the present invention are applicable to any suitable spread spectrum system. By way of example, mobile station 102a can operate in a simultaneous voice / data mode. Accordingly, one or more base stations 104-104n may convey broadcast forward pilot channel information and non-broadcast channel information (eg, traffic channels and dedicated control channels) to mobile station 102a. it can.
[0010]
Base stations 104a through 104n can be base station radios (BTSs) or any other suitable base stations capable of transmitting and receiving spread spectrum signals. The mobile station 102a can communicate with a plurality of base stations 104a through 104n via downlink (forward link) communications 106a through 106n, which includes a broadcast pilot channel, a plurality of traffic channels, A dedicated control channel or any other suitable information may be included. Mobile station 102 also communicates with one or more base stations 104a through 104n via uplink communications 108a through 108n. Other mobile stations can also communicate with one or more base stations, as is known in the art.
[0011]
The mobile station 102a performs a non-broadcast channel acquisition procedure according to the present invention. For example, mobile station 102a determines whether a bad frame was received when the receiver finger was locked to the appropriate forward pilot channel. This means, for example, that pilot energy may be sufficient but non-broadcast channel information is unacceptable. In this example, the mobile station notifies the corresponding base station to increase the transmission power of the assigned non-broadcast channel. If the mobile station receives a bad frame and the associated receiver channel element, such as a receiver finger, is not locked to the appropriate forward pilot channel, the mobile station will Return to the pilot channel quasi-acquisition state.
[0012]
FIG. 2 is a block diagram illustrating one example of a wireless communication device 200 such as a mobile station that receives a wireless spread spectrum signal 202. The wireless communication device 200 includes a receiver unit 204 and a transmitter unit 206. The receiver section 204 includes a radio frequency demodulator stage 208, a pilot searcher 210 (search receiver), a plurality of receiver channel elements 212 such as rake receiver fingers, a combiner 214, and a non-broadcast channel acquisition module 216. And a decoder 218.
[0013]
Radio frequency demodulator stage 208 performs conventional demodulation on spread spectrum signal 202, as is known in the art, and receives the received spectrum, such as a dedicated control channel, one or more traffic channels, and a pilot channel. Provides a digital output of the spread signal. This digital output information is collectively shown as reception channel information 220.
[0014]
A pilot searcher 210, such as a search receiver known in the art, searches for energy peaks in the pilot signal and, as is known in the art, a pilot indicating energy level and phase information. Operate to obtain a signal energy profile. Pilot searcher 210 generates pilot energy 222, such as Ec / Io, to obtain a pilot energy / time profile, as known in the art. This can also indicate, for example, the energy per chip (energy per chip). Pilot searcher 210 determines pilot signal phase information and a receiver channel element sample window and, based on the pilot energy peak window detected by searcher 210, places receiver channel element 212 within the reception window. Work to assign.
[0015]
Receiver channel element 212 may be a plurality of rake receivers, as known in the art, which receive control signals from appropriate control logic (not shown) and To receive a spread spectrum signal during a designated time frame. Each receiver channel element 212 generates received symbol information 224a and 224b, respectively, and these are input energy to interference power received per symbol (energy per symbol per received noise power) represented by Es / Ior. And the received symbol energy per channel such as Each receiver channel element 212 can receive multiple channels from a given base station, if needed. Each spread spectrum signal 202 received from various base stations can include different rates of spread spectrum information, for example, one traffic channel that can be considered a fundamental channel can be used for voice transmission. Information can be transmitted at a lower speed than the auxiliary channel available for data transfer. The received channel information 224a, 224b also includes correlated samples as known in the art. A combiner 214 appropriately combines the outputs from the various receiver channel elements to combine the combined sample outputs / channel at a symbol rate represented as information 226 for a decoder 218, as is known in the art. provide. Decoder 218 may be a Viterbi decoder, as known in the art, or other suitable decoder.
[0016]
Non-broadcast channel acquisition module 216 may be a suitably programmed processing device, such as a microprocessor, DSP, state machine, or other suitable combination of hardware, software, and firmware. Can be. Such a processing device may, for example, perform the necessary operations for the combiner 214, the Viterbi decoder 218, or other suitable functions in the receiver if necessary. The non-broadcast channel acquisition module 216 receives the pilot energy 222 and receives the combined sample output / channel 226 to generate non-broadcast channel performance and acquisition metrics. Non-broadcast channel acquisition module 216 uses this information to determine whether the pilot signal and / or the non-broadcast channel is of sufficient quality to demodulate. The non-broadcast channel acquisition module 216 generates channel acquisition control data 230 that increases the assigned non-broadcast channel transmission power for a transmitter, such as a transmitting BTS. , Used to facilitate non-broadcast channel acquisition.
[0017]
In one embodiment, the channel acquisition control data 230 requests the transmission of transmit power control information 232, such as power control bits stored in memory 234, and the assignments that receiver 204 is attempting to acquire. Used by the transmitter stage 206 to transmit the designated non-broadcast channel to be transmitted to the base station.
[0018]
The transmitter stage 206 includes a radio frequency (RF) transmitter 236, a digital-to-analog converter 238, a transmission control logic and data formatter 240, and an encoder 242. As is known in the art, encoder 242 receives transmission data 244 for transmission from RF transmitter 236. The transmission control logic and data formatter 240 properly controls the RF transmitter 236 via the analog gain control signal 250, as is known in the art, and as required by the protocol requirements of a given system. Provide appropriate data formatting to be performed. Transmission control logic and data formatter 240 outputs the formatted data and digital gain control information 252 to control the gain of digital-to-analog converter 238, as known in the art, and transmit power. Output control information 232 to provide fast closed loop power control between communication device 200 and an associated transmitter, such as a base station.
[0019]
Each receiver channel element receives a non-broadcast channel and a forward pilot signal, as is known in the art. The non-broadcast channel capture module determines whether the non-broadcast channel is initially captureable. This is performed by measuring the quality of both the received forward pilot signal and the non-broadcast channel to determine if the waveform can be accurately demodulated, and these measurements are based on the received symbol energy It includes, but is not limited to, a ratio of received symbol energy to incident noise power, a demodulated symbol error rate, and the like. If the non-broadcast channel cannot be acquired, the non-broadcast channel acquisition module 216 determines whether the forward pilot signal associated with the assigned non-broadcast channel is of acceptable quality. . Quality is determined based on pilot energy information 222 and the symbol error rate determined from information 226. The symbol error rate is determined by a Viterbi decoder 218, which actually calculates a distance metric that measures how much the modulation of the input signal deviates from the desired waveform, as is known in the art. I do. If the forward pilot signal is of acceptable quality based on the pilot energy level and / or symbol error rate or other suitable criteria, the non-broadcast channel acquisition module 216 may To increase the transmit power of the non-broadcast channel to facilitate non-broadcast channel acquisition. The base station is informed via channel acquisition control data 230 to increase the transmission power. The transmitter stage 206 responds to the reception of the channel acquisition control data 230 by the transmitter control logic 240, for example, by sending at least one power control bit on the reverse pilot channel to transmit the non-broadcast channel. The power control information 232 is transmitted. The non-broadcast channel acquisition module 216 first rechecks the quality of the forward pilot signal, not requested, but after detecting a bad channel frame and before being locked to the pilot channel. Until then, it is desirable not to generate the channel acquisition control data 230.
[0020]
Memory 234 may be any suitable register or any other suitable memory for storing transmit power control information 232, for example, for a transmitter as described in the CDMA2000 specification incorporated herein by reference. It can be.
[0021]
FIG. 3 shows a flowchart for an example of one method of acquiring a non-broadcast channel. The process begins at block 300 by setting a receiver channel element 212 and a combiner 214 for an assigned non-broadcast channel and waiting for a traffic frame to be received. As shown at block 302, the method includes determining whether the assigned non-broadcast channel is sequesterable. This includes, for example, determining whether a plurality of allowable consecutive non-broadcast channel frames have been detected. As is known in the art, Viterbi decoder 218 indicates that a non-broadcast channel frame has been correctly received. As shown in block 304, if a plurality of good consecutive frames were not detected, the method includes determining whether the forward pilot signal is still of acceptable quality. This can be done, for example, by rechecking the quality of the forward pilot signal. This is performed by evaluating the output from the receiver channel element. As indicated at block 306, the method includes, after rechecking the quality, determining whether the forward pilot signal is still of acceptable quality. If unacceptable, the process includes re-acquiring the pilot with a pilot searcher to determine a peak timing window for a particular received pilot signal. However, if a bad frame is detected and the pilot signal is of acceptable quality, the method proceeds to block 308, which sends traffic transmit power control information 232 to the base station to assign the assigned non- Instructing the base station to increase the power of the broadcast channel. Thus, the wireless communication device does not need to wait for a timeout period that occurs when receiving a bad frame. Instead, it signals a transmitter, such as a base station, in advance to increase the transmit power for the traffic channel, even if the pilot energy is of sufficient quality. In this way, with a rapid power increase occurring, the wireless communication device responds to the transmission of the transmission power control information during the non-broadcast channel acquisition phase by responding to the transmission of a good frame having an appropriate power level. Can be received quickly. As shown at block 310, the process effectively continues trying to capture multiple consecutive frames. However, if multiple consecutive frames are not received, for example, within a timing window, re-acquisition of the pilot signal occurs. However, during the timeout period, the method includes, before the predetermined timeout period expires, increasing the transmitter's transmission power to attempt to properly acquire the non-broadcast channel.
[0022]
FIG. 4 illustrates in more detail a method for acquiring a non-broadcast channel according to one embodiment of the present invention. As shown at block 400, the method includes performing pilot signal acquisition to lock a receiver channel element to an appropriate pilot signal. As shown at block 402, the method includes waiting for a frame from an assigned channel to which at least one of the receiver channel elements is assigned. As indicated at block 404, the method includes determining whether a good frame has been received. If a good frame has been received, the process proceeds to block 406, which includes determining whether two consecutive frames have been received. However, any suitable number of consecutive frames may be used to indicate that the channel has been properly acquired. As shown in block 408, if two consecutive frames have been received, the end of the capture initialization state has been reached, and the wireless communication device then proceeds to perform conventional communication with the transmitting station. Referring back to block 406, if only one good frame has been received, the process then continues with determining if another good frame has been received.
[0023]
Referring back to block 404, if a good frame was not received, the method rechecks the quality of the forward pilot signal and is still of appropriate quality, as shown in block 410. Determining whether or not it is. Thus, if the pilot signal is still locked, it means that the receiver channel element is still locked for a particular pilot channel, and the method uses transmit power control information (eg: Power control bits) have already been sent to determine if the power increase is indicated, as shown in block 412. For example, the method includes determining whether the transmission power control information has been repeatedly transmitted over a period of time. The acquisition transmit power control bit history is maintained during the channel acquisition phase. Sending the power control bits can generally tell the base station to increase the transmit power by 1 dB. If the base station is told to increase power, eg, three times during the channel acquisition phase, and indicates to the BTS that it has already been told to increase power, the system may include: Wait for the frame. In one embodiment, three passes are allowed to request the base station to increase the transmit power at three different times. After three passes, if the received frame is still of poor quality, the wireless communication device then waits for a timeout to occur and then attempts to re-establish lock on the pilot signal.
[0024]
If the power control bits have already been sent, the method includes detecting whether a good frame has been received. If the channel acquisition control data has not been sent and the power control bit has been sent and has not requested to increase the signal transmission power, the method sends the transmission power control information 232 to the base station. Signaling the base station to increase the transmit power via the reverse pilot channel. This is indicated by block 414. Accordingly, the method includes evaluating the forward pilot signal before determining whether the traffic channel is sequester, as shown at block 400, and then determining the acceptable pilot signal, as shown at block 410. If a sufficient number of traffic channel frames have not been detected, rechecking the quality of the forward pilot signal is included.
[0025]
Referring back to block 410, if a good frame has not been received and the pilot signal is not locked, the method returns to the pilot signal acquisition algorithm or phase, as shown in block 416. Reacquiring the pilot signal. The process begins, as indicated by block 418, when another channel needs to be acquired, for example, after receiving a channel assignment message.
[0026]
Referring back to FIG. 2, the wireless communication device can be incorporated into a mobile station or, if desired, into a base station. If incorporated into a base station, such as when used in a call originating state, similar steps are performed by the base station to obtain channel acquisition. As yet another example, if the wireless communication device is a mobile station that is part of a wireless spread spectrum communication system that includes a base station, the method of acquiring a non-broadcast channel includes: Receiving a channel assignment message from a base station via a paging channel. During this time, the mobile station receives a forward pilot signal associated with at least one non-broadcast channel identified in the channel assignment message. The mobile station assigns a receiver channel element to an assigned channel based on the channel assignment message. The mobile station reduces the non-broadcast channel acquisition latency in response to detecting a bad non-broadcast channel frame. The mobile station determines, based on the assigned pilot channel, whether the receiver channel element assigned to receive the non-broadcast channel is still locked to the forward pilot signal, and If the machine channel element is already locked to the forward pilot signal, by increasing the transmit power of the assigned channel to inform the base station to facilitate acquisition of the non-broadcast channel, Reduce waiting time for non-broadcast channel acquisition. The method also includes, if the received channel element is not locked to the forward pilot signal, attempting to lock to the forward pilot signal in response to detecting the bad frame. (See, for example, FIG. 4). The method also includes displaying an acquisition of the channel in response to detecting a plurality of consecutive channel frames.
[0027]
The above method and wireless communication device effectively detects the possible reasons why non-broadcast channel acquisition was not successful, and increases the transmit power during the non-broadcast channel acquisition procedure to provide the following: Attempts to inform the transmitter to wait for a frame to be sent. This helps the wireless communication device to reduce unnecessary latency for acquiring a non-broadcast channel. As mentioned, the method can be implemented by software algorithms, for example, using appropriately programmed devices, or can be implemented using other suitable configurations. Further, the method can be used for any suitable channel, including the forward traffic channel, and for dedicated control channels.
[0028]
It will be apparent to those skilled in the art that other variations and modifications of the present invention can be realized in various aspects, and it is to be understood that the present invention is not limited to the particular embodiments described. Accordingly, all variations and modifications or equivalents that fall within the spirit and scope of the basic principles disclosed and claimed herein are covered by the present invention.
[0029]
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a wireless spread spectrum communication system using a channel acquisition method according to one embodiment of the present invention.
FIG. 2 is a block diagram illustrating an example of a wireless communication device using a non-broadcast channel acquisition module according to one embodiment of the present invention.
FIG. 3 is a flowchart illustrating an example of a method for acquiring a non-broadcast channel in a wireless spread spectrum communication system according to an embodiment of the present invention.
FIG. 4 is a flowchart illustrating an example of a method for capturing a non-broadcast channel in a wireless spread spectrum communication system according to an embodiment of the present invention.

Claims (10)

A method for acquiring a non-broadcast channel in a wireless spread spectrum communication system including at least one mobile station and at least one base station, comprising:
Determining whether the non-broadcast channel can be captured by the mobile station;
Determining if the forward pilot signal associated with the non-broadcast channel is of acceptable quality if the non-broadcast channel cannot be acquired; and If the quality is good, notifying the base station to increase the transmission power of the non-broadcast channel to facilitate acquisition of the non-broadcast channel;
A method characterized by comprising: Determining whether the non-broadcast channel can be captured by the mobile station comprises determining whether a plurality of acceptable non-broadcast channel frames have been detected by the mobile station. The method of claim 1, wherein the method comprises: 2. The method of claim 1, comprising evaluating the forward pilot signal prior to determining whether the non-broadcast channel is captureable, wherein the forward pilot signal is acceptable. Determining the quality of the downlink pilot signal comprises rechecking the quality of the forward pilot signal if an acceptable number of non-broadcast channel frames have not been detected. how to. Notifying the base station to increase transmission power comprises sending at least one power control bit over an inverse pilot channel based on the rechecking of the quality of the forward pilot signal. 4. The method according to claim 3, comprising sending non-broadcast channel transmission power control information to the base station. The method of claim 1, wherein the quality of the forward pilot signal is based on at least one of a pilot energy measurement and a received symbol error rate. A communication device for receiving a wireless spread spectrum signal, comprising:
At least one receiver channel element that receives a non-broadcast channel and a forward pilot signal; and is responsive to the received non-broadcast channel and is capable of acquiring the non-broadcast channel. A non-broadcast channel acquisition module operable to determine: if the non-broadcast channel cannot be acquired, the forward pilot signal associated with the non-broadcast channel is acceptable. Operable to determine if the quality is acceptable; increasing the transmit power of the non-broadcast channel to acquire the non-broadcast channel if the forward pilot signal is of acceptable quality. A non-broadcast channel acquisition module operable to notify the transmitter to facilitate the communication;
A communication device characterized by comprising: The non-broadcast channel capture module determines whether the non-broadcast channel is captureable by determining whether a plurality of consecutive acceptable non-broadcast channel frames have been detected. The communication device according to claim 6, wherein The non-broadcast channel acquisition module evaluates the forward pilot signal prior to determining whether the non-broadcast channel is capable of being acquired, wherein an acceptable number of non-broadcast channel frames are generated. 7. The communication apparatus according to claim 6, wherein when no signal is detected, the quality of the forward pilot signal is rechecked. 9. The communication device according to claim 8, wherein:
A memory containing non-broadcast channel transmit power control information; and the non-broadcast channel operably coupled to the non-broadcast channel acquisition module and the memory to recheck the quality of the forward pilot signal. A transmitter operable to send the non-broadcast channel transmission power control information by sending at least one power control bit over a reverse pilot channel based on the communication channel acquisition module;
A communication device characterized by comprising: The communication device of claim 6, wherein the quality of the forward pilot signal is based on at least one of a pilot energy measurement and a received symbol error rate.

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