完善资料让更多小伙伴认识你,还能领取20积分哦, 立即完善>
我们正在使用一款 中频子系统芯片 AD9864,
现在已经可以从 SSI 数据输出接口读取到 IQ 数据. 但是调试的时候遇到个问题: 不知道如何根据芯片 SSI 接口输出的 ATT 和 RSSI 数值,计算输入到 AD9864 入口处的实际信号功率大小. 器件手册里描述的不是很明白,也没有给出计算公式之类的. 请问 ATT 数值和 RSSI 数值是需要换算成 dB 的?如何换算? 谢谢! |
|
相关推荐
1个回答
|
|
您好!
对于RSSI的计算,产品线工程师解释如下,供您参考。 The RSSI is a coarse "linear detector" that measure the ABS(I)+ABS(Q) value of the input signal has shown in figure 58. It is typically used in conjunction with the AGC since its output is compared to the programmable level set in the AGCR field. The RSSI is a 6-bit field (when enabled) in the SSI output data with a value of 60 corresponding to a 0 dBFS sinewave input at IF center ( and -6 dBFS corresponding to a a value of 30). If the VGA setting is known than it is possible to calculate the real power from the IQ output (within digital pas***and with higher accuracy) or the RSSI field (wider band with lower accuracy due to 6-bit linear resolution). For example, if its setting was set to 0 dB (i.e. ONLY VGA Enabled in figure 59) than a -32 dBm input signal will result in a -2 dBFS level (defined as IF "clip point") on the I/Q output. Hence 0 dBFS = -30 dBm is my reference point. If the signal generator was reduced by 4 dB to -36 dBm. I would expect the RSSI field to read closer to 30 since this corresponds to -6 dBFS). Note that the freqency offset from the IF center also introduces an additional error as shown in figure 60. Again, the RSSI function is typically used in conjunction with the AGC and only provides a coarse estimate of the signal power over the extended freq range of the 1st stage Dec-12 filter. |
|
|
|
只有小组成员才能发言,加入小组>>
1003 浏览 2 评论
给ADUM4223 增加信号驱动15V电压就不正常, 波动很大会被烧是什么情况?
1394 浏览 2 评论
ADP5092 SYS端口为2.09V,但是REG_OUT为0是什么原因?
1941 浏览 1 评论
ad7193差分输入ain1与ain2差是正值时,读到电压与实际值误差小,但为负值值,误差就变的很大
4275 浏览 2 评论
9068 浏览 1 评论
ADC3442采集,分析数据出现有规则毛刺,请问是哪方面的问题啊?
1553浏览 3评论
AD7190状态寄存器一直是0x80,连续转换模式下RDY不拉低
1700浏览 2评论
1003浏览 2评论
1683浏览 2评论
给ADUM4223 增加信号驱动15V电压就不正常, 波动很大会被烧是什么情况?
1394浏览 2评论
小黑屋| 手机版| Archiver| 电子发烧友 ( 湘ICP备2023018690号 )
GMT+8, 2024-12-28 01:16 , Processed in 0.699234 second(s), Total 46, Slave 40 queries .
Powered by 电子发烧友网
© 2015 bbs.elecfans.com
关注我们的微信
下载发烧友APP
电子发烧友观察
版权所有 © 湖南华秋数字科技有限公司
电子发烧友 (电路图) 湘公网安备 43011202000918 号 电信与信息服务业务经营许可证:合字B2-20210191 工商网监 湘ICP备2023018690号