RF Modulation Types for LMS6002D

Projects Reference Development Kit
1

Hi,

According to its datasheet, LMS6002D will supply WCDMA/HSPA, LTE, GSM, CDMA2000, IEEE® 802.16x
radios which uses different types of PSK or AM modulations.

For example, can I directly obtain O-QPSK RF modulation output at 5Mb/s datarate using LMS6002? Or should I use a third party modulator/demodulator chip?

Best regards,
Bora

2

Hi Bora,

The LMS600D chip is direct conversion transceiver, which takes digital signal (12 bit parallel with max 40 MHz sampling frequency) and converts it to RF domain and vice versa. So it will provide you raw IQ data, which will require some post processing to be involved to obtain the O-QPSK modulation.

Andrew

3

Hi Andrew,

What kind of post processing is required?

Are there any application note or example project available?

Perhaps ADF7242 or COM-1002 might be used with LMS600D?

Thanks for your support,

Bora

4

Hi Bora,

ADF7242 has its own transceiver running only in 2.4GHz region and supports narrow band modulation (up to 250 Kb/s) so it is not good and is not possible to connect it to LMS6002D.

COM1002 is purely digital modem able to implement BPSK/QPSK/OQPSK up to 20 Mbps (QPSK) and 10 Mbps (BPSK). You can connect it to LMS6002D if it is powerful enough for your application.

Please note that LTE and 802.16 are based on OFDM modulation which COM1002 can not cover.

You can also use base band processors dedicated to particular communication standards, general DSPs or even FPGAs.

Simon