LG LGP2300W Service Manual
1 LG Information & Communications, Ltd.
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Features of Mobile Subscriber RadioFeatures of Mobile Subscriber Radio
Telephone SetTelephone Set
(LG(LGPP--2300/23102300/2310 W Type)W Type)
1. Wave Type : G7W
2. Frequency Scope
• Send Frequency : 1850~1910MHz
• Receive Frequency : 1930~1990MHz
3. Rated Output
• 360mW
4. Output Conversion Method : This is possible by correcting the key board channel.
5. Voltage and Current Value of Termination Part Amplifier(Catalogue included)
Product Type Name Voltage Current Power
PWR AMP RI-21108U 5.0V 450mA 250mW
6. Functions of Major Semi-Conductors
Classification Function
MSM3000-PBGA Terminal operation control and digital signal processing
FLASH MEMORY
& STATIC RAM
(MB84VA2103-10)
Flash Memory (16Mbit) Õ Storing of terminal operation program
SRAM (2Mbit) Õ Temporary storing of the data created while busy
IFR3000 Converts IF signal into digital baseband signal
IFT3000 Converts digital baseband signal to IF signal
7. Frequency Stability
• ±0.1PPM
LGP-2300/2310W
LG Information & Communications, Ltd.
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CDMA Mobile Subscriber Unit
LGP-2300/2310W
SERVICE MANUAL
LGP-2300/2310W
LG Information & Communications, Ltd.
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LGP-2300/2310W
LG Information & Communications, Ltd.
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Table of ContentsTable of Contents
General Introduction
...................................................................................................................................................................... 3
CHAPTER 1. System Introduction
1. System Introduction ..................................................................................................................................... 4
2. Features and Advantages of CDMA Mobile Phone ...................................................................................... 4
3. Structure and Functions of CDMA Mobile Phone ........................................................................................ 8
4. Specification .................................................................................................................................................. 9
5. Installation ................................................................................................................................................... 12
CHAPTER 2. NAM Input Method(Inputting of telephone numbers included)
1. Telephone Number Input Method ................................................................................................................14
2. NAM Program Method ............................................................................................................................... 14
CHAPTER 3. Circuit Description
1. RF Transmit/Receive Part ........................................................................................................................... 15
2. Digital/Voice Processing Part ..................................................................................................... 20
CHAPTER 4. Trouble Shooting
................................................................................................................................................... 24
CHAPTER 5. Test Procedure
................................................................................................................................................... 31
Appendix
................................................................................................................................................... 32
1. Assembly and Disassembly Diagram
2. Block & Circuit Diagram
3. Part List
4. Component Layout
5. Accessories
- Desktop Charger
- Travel Charger
- Hands Free Kit
- Cigar Light Charger
- Data Kit
6. WLPST ( LGIC Product Support Tool For Win95 )
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The LGP-2300/2310W is a 1.9GHz CDMA(Code Division Multiple Access) PCS phone. CDMA technology
with this phone adopts DSSS(Direct Sequence Spread Spectrum) ,which is also used in the military.
This feature of DSSS enables the phone to keep communication from being crossed and to use one frequency
channel by multiple users in the same specific area, resulting that it increases the capacity 10 times more
compared with that in the analog mode currently used.
Soft/Softer Handoff, Hard Handoff, and Dynamic RF power Control technologies are combined into this phone
to reduce the call being interrupted in a middle of talking over the phone.
A CDMA PCS network consists of MSC (Mobile Switching Center), BSC (Base Station Controller), BTS (Base
station Transmission System), and MS (Mobile Station). Communication between MS and BTS is designed to
meet the specification of ANSI J-STD-008 (Common Air Interface). MS meets the specifications of the below:
- ANSI J-STD-008 Personal Station - Base Station Compatibility Requirements for 1.8 to 2.0
GHz CDMA PCS
- ANSI J-STD-018 Recommended Minimum Performance Requirements for 1.8 to 2.0 GHz
CDMA Personal Stations
- TIA/EIA IS-126-A Mobile Station Loopback Service Options Standard
- TIA/EIA IS-127 Enhanced Variable Rate Voice Coder
- TIA/EIA IS-683 Over-the-Air Service Provisioning of Mobile Stations in Wideband Spread
Spectrum Systems
- TIA/EIA-IS-707 Data Service Options for Wideband Spread Spectrum Systems
LGP-2300/2310W is composed of transceiver, desktop charger, Li-Ion Battery (1600mAh), h
ands-free kit,
travel charger, cigar light charger and data kit. Hands-free kit is designed to operate in full
duplex.
General Introduction
LGP-2300/2310W
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1. System Introduction
1.1 CDMA Abstract
Currently,2 methods of PCS services are in use worldwide; One is TDMA and the other is CDMA. DCS-
1800,which is based on the GSM protocol , TDMA technology, and 1.8GHz frequency range is in service in
many areas including Europe. Japanese PHS(Personal Handy-phone System) is based on the TDMA/TDD
technoogy and uses 1.9GHz frequency range. Meanwhile,in the United States,both of PCS-1900,a TDMA
standard,and J-STD-018,a CDMA standard have been adopted commercially.
CDMA system can be explained as follows: TDMA or SDMA can be used to enable each person to talk
alternately or provide a separate room for each person when two persons desire to talk with each other at the
same time, whereas FDMA can be used to enable one person to talk in soprano, whereas the other in bass (one
of the two talkers can carry out synchronization for hearing in case there is a bandpass filter function in the area
of the hearer).
Another method available is to make two persons to sing in different languages at the same time, space, and
frequency when wishing to let the audience hear the singing without being confused. This is the characteristics
of CDMA.
On the other hand, when employing the CDMA technology, each signal has a different pseudo-random binary
sequence used to spread the spectrum of carrier. A great number of CDMA signals share the same frequency
spectrum. In the perspective of frequency area or time area, several CDMA signals are overlapped. Among these
types of signals, only desired signal energy is selected and received through the use of pre-determined binary
sequence; desired signals can be separated and then, received with the correlator used for recovering the
spectrum into its original state. At this time, the spectrums of other signals that have different codes are not
recovered into its original state and instead, processed as noise and appears as the self-interference of the system.
2. Features and Advantages of CDMA Mobile Phone
2.1 Various Types of Diversities
When employing the narrow band modulation (30kHz band) such as the analog FM modulation used in the
existing cellular system, the multi-paths of radio waves create a serious fading. However, in the CDMA
broadband modulation(1.25MHz band), three types of diversities (time, frequency, and space) are used to reduce
serious fading problems generated from radio channels in order to obtain high-quality calls.
Time diversity can be obtained through the use of code interleaving and error correction code whereas
frequency diversity can be obtained by spreading signal energy to wider frequency band. The fading related to
normal frequency can affect the normal 200~300kHz among signal bands and accordingly, serious effect can be
CHAPTER 1. System Introduction
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avoided. Moreover, space diversity (also called path diversity) can be realized with the following three types of
methods.
First, it can be obtained by the duplication of cell site receive antenna. Second, it can be obtained through the
use of multi-signal processing device that receives a transmit signal having each different transmission delay
time and then, combines them. Third, it can be obtained through the multiple cell site connection (Soft Handoff)
that connects the mobile station with more than two cell sites at the same time.
2.2 Power Control
The CDMA system utilizes the forward (from a base station to mobile stations) and backward (from the mobile
station to the base station) power control in order to increase the call processing capacity and obtain high-quality
calls. In case the originating signals of mobile stations are received by the cell site in the minimum call quality
level (signal to interference) through the use of transmit power control on all the mobile stations, the system
capacity can be maximized.If the signal power of mobile station is received too strong, the performance of that
mobile station is improved. However, because of this, the interference on other mobile stations using the same
channel is increased and accordingly, the call quality of other subscribers is reduced unless the maximum
accommodation capacity is reduced.
In the CDMA PCS system, forward power control, backward open loop power control, and closed loop power
control methods are used. The forward power control is carried out in the cell site to reduce the transmit power
on mobile stations less affected by the multi-path fading and shadow phenomenon and the interference of other
cell sites when the mobile station is not engaged in the call or is relatively nearer to the corresponding cell site.
This is also used to provide additional power to mobile stations having high call error rates, located in bad
reception areas or far away from the cell site.
The backward open loop power control is carried out in a corresponding mobile station; the mobile station
measures power received from the cell site and then, reversely increases/decreases transmit power in order to
compensate channel changes caused by the forward link path loss and terrain characteristics in relation to the
mobile station in the cell site. By doing so, all the mobile transmit signals in the cells are received by the cell site
in the same strength.
Moreover, the backward closed loop power control used by the mobile station is to control power with the
commands issued out by the cell site. The cell site receives the signal of each corresponding mobile station and
compares this with the pre-set threshold value and then, issues out power increase/decrease commands to the
corresponding mobile station every 1.25msec (800 times per second). By doing so, the gain tolerance and the
different radio propagation loss on the forward/backward link are complemented.
2.3 Voice Encoder and Variable Data Speed
The bi-directional voice service having variable data speed provides voice communication which employs voice
encoder algorithm having power variable data rate between the mobile telephone cell site and mobile station. On
the other hand, the transmit voice encoder performs voice sampling and then, creates encoded voice packets to
be sent out to the receive voice encoder, whereas the receive voice encoder demodulates the received voice
packets into voice samples.
One of the two voice encoders described in the above is selected for use depending on inputted automatic
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conditions and message/data; both of them utilize four-stage frames of 14400,7200,3600,1800 bits per second.
In addition, this type of variable voice encoder utilizes adaptive threshold values when selecting required data
rate. It is adjusted in accordance with the size of background noise and the data rate is increased to high rate only
when the voice of caller is inputted.
Therefore, background noise is suppressed and high-quality voice transmission is possible under the
environment experiencing serious noise. In addition, in case the caller does not talk, data transmission rate is
reduced so that the transmission is carried out in low energy. This will reduce the interference on other CDMA
signals and as a result, improve system performance (capacity increased by about two times).
Also,compared to the existing CDMA cellular system’s 9600 bps vocoder rate,the PCS’ vocoder rate is up to
14400 bps, providing relatively better voice quality (almost twice better than the existing 800MHz CDMA
cellular system) almost comparable to the landline service.
2.4 Protecting Call Confidentiality
CDMA signals have the function of effectively protecting call confidentiality by spreading and interleaving call
information in broad bandwidth. This makes the unauthorized use of crosstalk, search receiver, and radio very
hard substantially. Also included is encryption function on various authentication and calls for the double
protection of call confidentiality.
2.5 Soft Handoff
During the soft hand-off, the cell site already in the busy state and the cell site to be engaged in the call later
participate in the call conversion. The call conversion is carried out through the original call connection cell site,
both cell sites, and then, new cell site. This method can minimize call disconnection and prevent the user from
detecting the hand-off.
2.6 Frequency Re-Use and Sector Segmentation
Unlike the existing analog cellular system, the CDMA system can reuse the same frequency at the adjacent cell
and accordingly, there is no need to prepare a separate frequency plan. Total interference generated on mobile
station signals received from the cell site is the sum of interference generated from other mobile stations in the
same cell site and interference generated from the mobile station of adjacent cell site. That is, each mobile
station signal generates interference in relation to the signals of all the other mobile signals.
Total interference from all the adjacent cell sites is the ratio of interference from all the cell sites versus total
interference from other mobile stations in the same cell site (about 65%). In the case of directional cell site, one
cell normally uses a 120°sector antenna in order to divide the sector into three. In this case, each antenna is
used only for 1/3 of mobile stations in the cell site and accordingly, interference is reduced by 1/3 on the average
and the capacity that can be supported by the entire system is increased by three times.
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2.7 Soft Capacity
The subscriber capacity of the CDMA system is flexible depending on the relation between the number of users
and service classes. For example, the system operator can increase the number of channels available for use
during the busy hour despite the drop in call quality. This type of function requires 40% of normal call channels
in the standby mode during the handoff support, in an effort to avoid call disconnection resulting from the lack
of channels.
In addition, in the CDMA system, services and service charges are classified further into different classes so that
more transmit power can be allocated to high class service users for easier call set-up; they can also be given
higher priority of using hand-off function than the general users.
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3. Structure and Functions of CDMA Mobile Phone
The mobile station of the CDMA system is made up of a radio frequency part and a logic/control (digital) part.
The mobile station antenna is connected with the transmitter/receiver via a duplexer filter so that it can carry out
the transmit/receive function at the same time.
The transmit frequency is the 60MHz band of 1850~1910MHz , whereas the receive frequency is the 60MHz
band of 1930~1990MHz. The transmit/receive frequency is separated by 20MHz. The RF signal from the
antenna is converted into intermediate frequency(IF) band by the frequency synthesizer and frequency down
converter and then, passes the bandpass SAW filter having the 1.25MHz bandwidth. The IF output signals that
have been filtered from spurious signals are converted into digital signals via an analog-to-digital
converters(ADC) and then, sent out respectively to 5 correlators in each CDMA de-modulator. Of these, one is
called a searcher whereas the remaining 4 are called data receivers(fingers). Digitalized IF signals include a great
number of call signals that have been sent out by the adjacent cells. These signals are detected with pseudo-noise
sequence (PN Sequence). Signal to interference ratio (C/I) on signals that match the desired PN sequence are
increased through this type of correlation detection process. Then, other signals obtain processing gain by not
increasing the ratio. The carrier wave of pilot channel from the cell site most adjacently located is demodulated
in order to obtain the sequence of encoded data symbols. During the operation with one cell site, the searcher
searches out multi-paths in accordance with terrain and building reflections. On three data receivers, the most
powerful 3 paths are allocated for the parallel tracing and receiving. Fading resistance can be improved a great
deal by obtaining the diversity combined output for de-modulation. Moreover, the searcher can be used to
determine the most powerful path from the cell sites even during the soft handoff between the two cell sites.
Moreover, 3 data receivers are allocated in order to carry out the de-modulation of these paths. Data output that
has been demodulated change the data string in the combined data row as in the case of original
signals(deinterleaving), and then, are de-modulated by the forward error correction decoder which uses the
Viterbi algorithm.
On the other hand, mobile station user information sent out from the mobile station to the cell site pass through
the digital voice encoder via a mike. Then, they are encoded and forward errors are corrected through the use of
convolution encoder. Then, the order of code rows is changed in accordance with a certain regulation in order to
remove any errors in the interleaver. Symbols made through the above process are spread after being loaded onto
PN carrier waves. At this time, PN sequence is selected by each address designated in each call.
Signals that have been code spread as above are digital modulated (QPSK) and then, power controlled at the
automatic gain control amplifier (AGC Amp). Then, they are converted into RF band by the frequency
synthesizer synchronizing these signals to proper output frequencies.
Transmit signals obtained pass through the duplexer filter and then, are sent out to the cell site via the antenna.
LGP-2300/2310W
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4. Specification
4.1 General Specification
4.1.1 Transmit/Receive Frequency Interval : 80 MHz
4.1.2 Number of Channels (Channel Bandwidth) : 48
4.1.3 Operating Voltage : DC 3.8V
4.1.4 Battery Power Consumption : DC 3.8V
SLEEP IDLE MAX POWER
CDMA
3 mA 100 mA 450 mA (24 dBm)
4.1.5 Operating Temperature : -20°° ~ +60°°
4.1.6 Frequency Stability : ±±0.1PPM
4.1.7 Antenna : Retractable Type (Herical+Whip), 50 W
4.1.8 Size and Weight
1) Size : 126523.7548( , L 5 D 5 W)
2) Weight : 155g (approximately with extended battery)
4.1.9 Channel Spacing : 1.25MHz
4.1.10 Battery Type, Capacity and Orerating Time. ( condition: Slot Cycle 2)
Extended (1600mAh)
Stand-By Time CDMA
200 Hrs.(SCI = 2)
Talk Time CDMA
180 Min.(typical duplexer,10dBm output)
4.2 Receive Specification
4.2.1 Frequency Range : 1930 MHz ~ 1990MHz
4.2.2 Local Oscillating Frequency Range : 1719.62MHz ∼∼ 1779.62MHz
4.2.3 Intermediate Frequency : 210.38MHz
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