Sony CMD-J5/J16 Section Diagrams, Block Diagram Radio Frequency RF, General RF Indications

SECTION 6

DIAGRAMS

6.1 Block Diagram - Radio Frequency (RF)

Rx frontend filter

Rx interstage filter

DCS

LNA

1st Rx mixer

IF

IQ Demodulator

RF

IF

SAW Filter

Ceramic Filter

SAW Filter

440 MHz

IF Amplifier (PGC)

I

LO

BB amplifier and

1805..1880 MHz

1805..1880 MHz

90°

∑

0

low pass filter

GSM

LNA

°

Q

RF

IF

RX:

SAW Filter

SAW Filter

GSM 1365..1400 MHz

LO

DCS 1365..1440 MHz

925..960 MHz

925..960 MHz

440 MHz

RX

LO1 (RF) PLL:

Antenna

1

- RX -

GSM 1365..1400 MHz

LNA Bias

Transceiver

2

DCS 1365..1440 MHz

- TX -

control

MHz

Antenna

GSM 1370..1440 MHz

880

DCS 1385..1460 MHz

Switch

TX:

RF Connector with

GSM 1370..1440 MHz

mechanical switch

DCS 1385..1460 MHz

TX

LO2 (IF) PLL

RX 880 MHz

Detector and

TX 975 MHz

2

APC loop

Level control

DCS

GSM

1

MHz

5

TX:

1

GSM

Pin diode

Tx GSM VCO

GSM 685..720 MHz

975

880..915 MHz

switch

880..915 MHz

DCS 1385..1460 MHz

3/5

GSM :5

1

DCS :3

Directional

PA

LP Filter

coupler + LPF

Down

LP Filter

Converter

DCS1800

Pin diode

Tx DCS VCO

1710..1785 MHz

switch

1710..1785 MHz

Sum loop

Loop

Filter

ϕ

I

Directional

PA

LP Filter

∑

90°

0

coupler

Phase

°

detector

GSM 195 MHz

Q

DCS 325 MHz

IC 1

Digital

DET_EN

TX_SW_EN

GSM_TX_EN

GSM_VCO_EN

RF_IC_EN

DET_TX

signals

TXP_OFS_EN

APC_DOWN

DCS_TX_EN

DCS_VCO_EN

IC 2

Analog

AUX_DAC

TXP

signals

VCC_RF LDO

RF_EN

VCC_SYNTH LDO

RXIP

RXIN

RXQP

RXQN

VCTCXO	AFC
13 MHz	CLK13M

NLO1 (RF) PLL

		N+1	200 kHz step
Total VCO Range:		1
1365 to 1460 MHz		ϕ
			N
			1
LO1	Loop
VCO	Filter
		PLL
		ϕ	N
			1
LO2	Loop
VCO	Filter	M	LO2 (IF) PLL
Total VCO Range:		1	1 MHz step
880 to 975 MHz

SERCK

SERDA

SERLE1

SERLE2

TXIP

TXIN

TXQP

TXQN

6.1.1 General RF Indications

The radio part of the CMD-J5/J16 handles the air interface according to the GSM specifications. It is the main contributor for the dualband functionality for E-GSM 900 and DCS 1800.

Receiver

The receiver consists of two separated RF paths for GSM and DCS 1800 each.

On the transmission line between the antenna switch of the RF part and the antenna there is the RF connector including a mechanical switch to connect an external antenna for accessory use. The integrated mechanical switch switches between the helix antenna and the external RF antenna connection. As long as a plug is connected the antenna is deactivated and all RF signals go across the connector.

The GMSK (Gaussian-filtered minimum shift keying) modulated 900 MHz / 1800 MHz signal received by the antenna is filtered, gained and downconverted into the baseband via an intermediate frequency of 440 MHz.

The 440 MHz filter is followed by a tuneable amplifier and IQ demodulator. Behind the demodulator there are additional base band amplifiers and low pass filters.

The In Phase (I) and Quadrature (Q) signal outputs are balanced each.

A13 MHz voltage-controlled-temperature-compensated crystal oscillator (VCTCXO) generates the clock frequency for the PLL and baseband part.

Transmitter

In the transmit direction the digitally GMSK-modulated baseband signal is upconverted to the transmit frequency in the 900 MHz / 1800 MHz band via an intermediate frequency of 195 MHz (GSM) / 325 MHz (DCS 1800) by means of an IQ modulator and the subsequenting sum loop.

All RF and IQ signals are balanced signals in order to suppress crosstalk effects. According to GSM recommendations transmitter and receiver are never active at the same time.

(TDMA system “Time Division Multiple Access”).

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