This week, the overall grades of five communications equipment stocks are lower, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

ARRIS Group, Inc. (ARRS) is on the decline this week, earning a D (“sell”) after receiving a C (“hold”) last week. ARRIS is a global communications technology company specializing in the design and engineering of broadband network solutions. For more information, get Portfolio Grader’s complete analysis of ARRS stock.

Applied Optoelectronics, Inc. (AAOI) ratings are on the decline this week as the company earns an F (“strong sell”). Last week, it received a C (“sell”). The stock gets F’s in Earnings Surprise and Cash Flow. As of March 26, 2015, 11.4% of outstanding Applied Optoelectronics, Inc. shares were held short. The stock has a trailing PE Ratio of 49.00. To get an in-depth look at AAOI, get Portfolio Grader’s complete analysis of AAOI stock.

Dragonwave Inc. (DRWI) gets weaker ratings this week as last week’s C drops to a D. DragonWave is a producer of high-capacity packet microwave solutions which support networking and other data transmission needs. The stock gets F’s in Equity and Cash Flow. For more information, get Portfolio Grader’s complete analysis of DRWI stock.

Clearfield, Inc.’s (CLFD) rating weakens this week, dropping to an F versus last week’s D. Clearfield offers telecommunications equipment and products in the United States. The stock gets F’s in Earnings Growth, Earnings Momentum and Sales Growth. Shares of the stock have been exchanging at an usually rapid pace, twice the rate of the week prior. The stock’s trailing PE Ratio is 44.20. To get an in-depth look at CLFD, get Portfolio Grader’s complete analysis of CLFD stock.

The rating of Sonus Networks, Inc. (SONS) declines this week from a C to a D. Sonus Networks provides voice infrastructure solutions for wireline and wireless service providers. Shares of the stock are being traded at a very rapid pace, up 771.4% from the week prior. For more information, get Portfolio Grader’s complete analysis of SONS stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.